KR> Don Reid

[Donald Reid]

I'm still around but not actively building.  As a result of a divorce, all of 
my airplane stuff is in a hangar about two hours away from my condo.  I have no 
workshop any more.

Sent from my iPad

> On Jun 14, 2014, at 3:24 AM, Dene via KRnet  wrote:
> 
> Does anyone know what happened to Donald Reid?
> I see he hasn't updated his website in years and his plane was pretty close
> to flying at that stage.
> 
> Regards
> Dene Collett
> www.denecollett.com
> 
> 
> 
> ---
> This email is free from viruses and malware because avast! Antivirus 
> protection is active.
> http://www.avast.com
> 
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> options

KR> KR Crash

[Donald Reid]

Still here but not currently active.  After a divorce, the unfinished
plane is in my hangar, but I live almost two hours away.

I don't know the pilot or plane involved.

On Fri, Oct 7, 2011 at 9:17 AM, Scott Stanton  wrote:
> Is Don Reid still on the net?  That's a bit away from his place, but
> it's not out of the realm of possibility.
>

KR> [Informal!] poll on revival of McCulloch 4318 engines . . . . . . . . .

[Donald Reid]

On Sat, Jun 11, 2011 at 2:48 PM,   wrote:
 Really weird ignition firing sequence:  front two cylinders fired
simultaneously, then aft two cylinders fired simultaneously - - I have
never read or heard an explanation for this oddity,

There is a really simple explanation for the firing sequence. In a
2-stroke engine, the fuel-air-oil mixture goes into the crankcase to
lubricate the bearings, and is then compressed slightly by the
downstroke of the piston(s) before entering the combustion chamber(s)
when a port opens up near the bottom of the stroke. The MAC engine has
two separate crankcase cavities; one for the front two and one for the
rear two cylinders.

A "normal" boxer engine sequence wouldn't pressurize the crankcase.

> How many readers would be interested in a revival of a ('modernized') 
> up-dated Mac 72-type engine???

I would. I have three of these engines, two are brand new and still in
the original shipping cases.  The third had a prop strike after about
an hour.

KR> Cooper Flyin

[Donald Reid]

At 10:03 AM 5/2/2010, you wrote:
> > This morning I'm thinking more clearly and my decision is to have the
> > flyin as planned. I understand that some of you may prefer to go to the
> > Virginia Festival of Flight and thats OK, but I will be here and have the
> > hangar doors open, hope you can come.
>
>Good for you!  I meant to email you last night and let you know that was my
>opinion as well, but never got around to it.  If nothing else, you, Dan, and
>I will stand around and talk KRs and Corvairs all day (weather permitting).
>Anybody else is welcome to be there too...

Thanks to Jack for mentioning the Virginia Festival of Flight.  It's 
not too far from East Tennessee to Suffolk Virginia and I hope to see 
some of you there.  New this year, we will be having a 60 mile, timed 
Rally along a triangular course on Sunday morning.  It would be great 
to see some KRs flying in that event.

That will be my second show in a row.  On the weekend of the 14th, 
15th and 16th, I will be a Lumberton NC http://mafsac.com/ doing 
their photography. On the 22nd and 23rd, I will be in Suffolk where 
I'm the web master and photographer.

I hope to see you there.

Donald Reid

Visit my websites at:
AeroFoil, A 2-d Airfoil Design And Analysis Program - 
http://aerofoilengineering.com
Virginia Regional Festival Of Flight - http://virginiaflyin.org
EAA Chapter 231 - http://eaa231.org/

KR> Virginia Festival of Flight

[Donald Reid]

At 04:24 PM 5/25/2009, you wrote:
>Don Reed,
>Are you going to be at the Virginia show this year?? I tried to make 
>it last year but got weathered out before crodding the bay/brigdge 
>tunnel and turned back. I was going to try again this year just for 
>the day on Saturday and was hoping to meet you.
>Joe Horton,
>Coopersburg, Pa.
>N357CJ
>
>PS for the rest of you guys I love long weekends, So far I flew 
>everyday for well over a thousand miles and 8 1/2 hours and I just 
>might do it again before dark.


I'm going to be at the Virginia Regional Festival of Flight once 
again as the photographer and webmaster.  Pictures of KRs are always 
posted on the web site.  All of the Va information is posted on the 
web and it should be a good event.

I just got back from the Lumberton North Carolina show where I serve 
as the photographer.  No KRs but it was a good show and a great weekend.

Donald Reid

Visit my websites at:
AeroFoil, A 2-d Airfoil Design And Analysis Program - 
http://aerofoilengineering.com
Virginia Regional Festival Of Flight - http://virginiaflyin.org
EAA Chapter 231 - http://eaa231.org/

KR> airfoil question for Don Reid

[Donald Reid]

At 09:51 PM 2/15/2007, you wrote:
>Don: are you the author of AeroFoil, the airfoil analysis program, or are
>there other Don Reids in the world?
>
>KR content: Don is one of the resident (and credentialed) aero engineers on
>the KRNet.  He doesn't toss out many posts, but when he does- it's worth
>reading what he has to say.  Building a "KR Plus", to go with his size-12
>sneakers ;o)

Yes. that is me.  There was a post on the Yahoo airfoil group that 
Oscar just read that mentioned my name because I wrote a fairly good 
airfoil design and analysis computer program.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> spinner

[Donald Reid]

At 09:52 PM 12/23/2006, you wrote:
>in what direction will a spinner travel when it breaks off in flight 
>or on the ground ???

All you can say is that it will be ejected outward, more or less in 
the plane of prop rotation, until it impacts a prop blade.  When this 
happens, it will go almost anywhere.  During a ground run-up, you 
should never stand in the plane of the prop rotation.  That is the 
most likely place to get hurt.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> deihl wheel fairings

[Donald Reid]

At 09:02 AM 11/30/2006, you wrote:
>Hi,
>
>I have a quote from Dan Deihl for wheel fairings. I don't quite understand
>what these bits are ( us/uk english differences )
>
>Can someone please confirm my understanding.
>
> >Pete,
> >You need upper and lower fairings for $100 US and 2 wheel pants for $160 US.
>
>the upper fairings go around the legs and are attached to the wing skins.
>the lower fairings go around the lower legs and attach to the pants.
>the pants are the aerodynamic teardrops that fit around the wheels.

It may help to say that our UK cousins say spats when we say wheel pants.

Now ask the definition of a napkin.  In the US, it is the cloth that 
is used to clean your mouth and hands during a meal.  In the UK, it 
is the cloth that is used on a baby's bottom.  That can lead to 
severe differences in understanding.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Aileron trim tabs??

[Donald Reid]

At 05:13 PM 11/28/2006, you wrote:
>Barry,
>
>I would suggest putting a trim tab on the WING, NOT
>the AILERON..  Ailerons are self-centering in flight.
>All they will do is move the stick left or right from
>center..  Think about it everyone!!  Don't believe me,
>try it for yourself..

  What Ron said about the aileron being self-centering is incorrect; 
however, it will move the stick left or right.  Putting one on the 
wing would work, but it would have to be significantly larger than if 
it were on the aileron.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> EAA SPORT AVIATION

[Donald Reid]

At 03:45 PM 11/29/2006, you wrote:
>Check out this issues Cover Story
>http://www.eaa.org/benefits/sportaviation/index.html
>
>Mark Jones (N886MJ)


Sweet!



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Cracked spar

[Donald Reid]

Speaking as a Professional Engineer, your only safe course of action 
is to replace the spar.  I do not believe that you could ever make a 
satisfactory repair.  When the bracket failed, all of the load was 
transferred to the remaining bolts which split the wood.  The bracket 
failed because of inadequate design or faulty construction.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> VSI

[Donald Reid]

At 01:19 AM 9/15/2006, you wrote:

>For interest sake, does anybody know exactly how these things work. I know
>it measures the rate of change in static pressure but then the needle should
>return to zero or at least move in that direction if I keep a constant
>pressure on the rear port with my finger.


It is a small pressure chamber with a calibrated hole and a needle 
that connects to a diaphragm on the chamber.  The hole lets air in 
and out of the chamber slowly.  When pressure is equal inside and 
outside, the needle should point to zero.  The needle moves based on 
the rate of pressure change.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> COMMON BUILDING PRACTICES

[Donald Reid]

At 11:29 PM 8/24/2006, you wrote:

>   Why do Prop makers tighten their layers of wood together so 
> tightly when making a prop if it is a bad idea ?
>   Have you ever been in a prop shop. There used to be one near me 
> here in Caddo Mills Tx and they used house jacks to tighten the 
> wood together and left it that way until the resin/glue cured. I 
> have no idea what glue they used but what takes more of a beating 
> than a propeller taking pulses from the engine and air it is moving 
> through, besides trying to sling itself apart. Just wondering ? 
> Maybe their glue is really thick resin ? and will not all squeeze out.
>   Larry H.

Required clamping pressure is dependent on the type of 
glue.  Certificated wooden props must be built exactly the same way 
that they were certificated.  Certificated wood glues must be applied 
exactly as specified.  Resorcinol glue is certificated and requires 
fairly high clamping pressure; whereas, T-88 can be used to make 
repairs in a certificated airplane if you prove to the AI that it is 
an acceptable method but it must not be subjected to high clamping pressure.

The short answer is: read and heed the manufacturer's 
directions.  They know a whole lot more about it than you or I do.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> EAA aviation expo

[Donald Reid]

At 09:39 PM 7/27/2006, you wrote:
>Is anyone by chance planning to be at the EAA Aviation Expo in 
>Petersburg Va. at the end of September ?.


I am sorry that it took me so long to reply to this message but I 
have been out of the area.

I will be there, even though the plane is (still) not finished.  I am 
the web master and photographer for the Fly-In.  I promise you that 
any KRs that show up will be displayed on the web site.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Vortex Generators

[Donald Reid]

At 08:45 AM 7/22/2006, you wrote:
>My KR2 (built by others) was fitted with heaps of VGs under the 
>horizontal stab, on the fuselage prior to the rudder, on the landing 
>gear and in front of the canopy. A previous archive search suggested 
>that it lowers stall speed and if placed correctly has no speed 
>effect.  There are none placed on the main wing (original aerofoil).
>I don't understand why the previous owner wanted to lower the stall 
>speed of the horizontal stab, but not the main aerofoil...and why 
>the association with the rudder and canopy?  Were they just VG crazy?
>Any thoughts?

The vortex generators upstream of the tail surfaces will/can improve 
control authority at low speed by keeping the airflow attached to the 
elevator or rudder when they are deflected.  As for the gear, canopy, 
and other non wing-type surface, the only reason to put them there 
that I can think of is that the previous owner did not know what he 
was doing.

Tripping the flow from laminar or turbulent to separated in a 
controlled manner (which is what a vortex generator does) can 
sometimes reduce drag, but only if it is done correctly.  A vortex 
generator is not the proper way to do this.  I suggest that those can 
be removed and you will not notice any difference.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Open Cockpit KR2?

[Donald Reid]

At 07:41 PM 7/15/2006, you wrote:
>Is anybody flying a KR2 open cockpit with a partial canopy?  If I 
>seal the back off with an extended backrest will it work, and fly 
>right?  I would want it to have have interchangeable canopy 
>depending on our miserable Houston summer weather.

Go to http://aerofoilengineering.com/KR/sportaviation/kr_SA.htm
and select the miscellaneous photos link.  There is a photo of an 
open cockpit KR1



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Open Cockpit KR2?

[Donald Reid]

At 06:09 PM 7/17/2006, you wrote:
>Hi
>
>Before anyone considers an open cockpit please read the accidents report
>that Mark collated at http://home.hiwaay.net/~langford/KRaccidents.doc (just
>search the document for "canopy").
>The are 4 accident from canopies coming open in flight, 3 are Fatal.  It
>appears that aerodynamics to the tail feathers may be interrupted.  With the
>right windshield it may be OK, but not for me :-)

There is no comparison between a cockpit coming open in flight versus 
an open cockpit KR.  When a side-hinged cockpit comes open, the 
airflow is significantly altered, not to mention the pilot's reaction 
to stop flying the plane and try and close the cockpit.  There have 
been at least two open cockpit KRs.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Dang Tall People

[Donald Reid]

At 12:37 AM 7/12/2006, you wrote:
>Hi,
>
> I apologize if this question has been beat to death... I am
>relatively tall (6-4) and most of my height is in my legs (36"
>inseam). I was wondering if any of you are similarly proportioned and
>if you fit reasonably in your KR? Any special mods. to accommodate you?
>
>Thanks for your help, Ron Tyler

I am taller and have longer legs and it can be done.  You would have 
to make some extensive modification.  I started by making a cockpit 
mockup to check all dimensions.  If you do this kind of change, you 
will not be able to use any of the pre-fabricated parts.  If you 
tried to use any of them, they would also require extensive modification.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> wicks KR 7533 cloth

[Donald Reid]

At 07:04 PM 7/8/2006, you wrote:
>Hi netters,
>
>I was curious if Wicks KR 7533 cloth is strong enough for a composite
>fuselage shell? Im using foam and glass or carbon fiber for my covering. Well
>this suffice or should I use something else?

That is exactly like asking if the ice is thick enough to drive your 
car on.  You need to know lots of things before that question can be 
asked.  It is not possible to design a structure by saying :"that 
looks about right"



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Turtle deck

[Donald Reid]

At 09:13 AM 6/29/2006, you wrote:
> I have just finished the basic structure for the turtle deck 
> from wood, it seems pretty strong, I can almost stand on it but am 
> not game to try, it weighs about 4 lbs, with the ply skin still to 
> be fitted, the sheet of ply for the skin weighs 5 lbs and I will 
> use about 2/3 of the sheet, so all up the turtle deck from wood 
> will weigh about 7 lbs, my question is, how does this compare 
> weight wise to a composite structure?

I made a female mold and did a layup with three plies of light weight 
glass with foam and glass "ribs" at each bay location.  It probably 
weighed a little less but it was significantly more work.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Building Question

[Donald Reid]

At 06:34 PM 6/19/2006, you wrote:
>What do the people that have built / building this type of aircraft 
>think, am I taking on to much for a first project?
>
>The information that I have seen estimates 800 hours of building 
>time and a little over $10,000.00, does that sound correct?

If you want to have a scratch-built project, this is a good one.  The 
lowest actual building time that I have ever heard of was 1200 
hours.   I want mine to be perfect and I am to 8000.  It is all a 
matter of what you are personally willing to accept.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> RE: KR Net / now speed

[Donald Reid]

At 08:20 PM 6/21/2006, you wrote:
>What makes the wheel pants a pressure recovery type?

It is based on the thickness profile of the airfoil.  It is one way 
of describing a profile that will support the formation of a 
significant amount of laminar flow and minimize the formation of any 
airflow separation.  Its point of maximum thickness is far back and 
the trailing edge tapers rapidly.

In general terms, you can compare the shape of a NACA 63-015 to a 
NACA 66-015.  The point of maximum thickness of the 66 series is much 
farther back than on the 63 series.  At a Reynolds number of 3 
Million, a 63-015 has a minimum coefficient of drag of 0.0060 and 
will go to approximately +/- 4 degrees angle of attack with no change 
in the drag.  At the same Reynolds number, a 66-015 will have a 
minimum coefficient of drag of 0.0045 but will only go to 
approximately +/- 3 degrees angle of attack with no change in the drag.

That means that a NACA 66-015 would be a much better basis for wheel 
pants than a NACA 63-015.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

Re: Réf. : Re: KR> WAF Bolt Sheer Load

[Donald Reid]

At 04:19 AM 6/12/2006, you wrote:
>Phil, what would the compression member look like exactly?
>
>A better design is to use one long bolt with a
>compression member between the WAF pairs instead of paired short
>bolts, placing the joint in a balance double shear.   This is my
>considered opinion as a professional engineer.
>
>This is the requirement in Australia.

It is simply a relatively heavy wall piece of tubing that has been 
cut to the correct length in a lathe.  It should be a press-fit 
between the fittings so that there is no bending stress.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> WAF Bolt Sheer Load

[Donald Reid]

At 02:10 PM 6/9/2006, you wrote:
>I read an explanation some years ago in the KR newsletters that the 
>WAF are clamped to the spars and generate their holding action by 
>friction.  The 3/16 attach bolts are stressed primarily in tension 
>not in sheer.
>Another newsletter article reported on KR-2 main spar testing.  The 
>ultimate breaking force on the spar was 21g.  (I don't know how hard 
>folks fly their KRs, but 6g would be much more than enough to break 
>parts of me.)  One surprise was: The point of failure was about 12 
>inches inboard of the WAF and not at the WAF.  After the test the 
>WAFs were dismantled and examined for sheer damage.  There was no 
>evidence of any sheer stress on the eight WAF nor the AN3 and AN6 
>bolts. The report did not say there was not any sheer force, just no 
>evidence.  I guess they did not find any dents in the bolts.

I wrote one article that you are referring too.  That was in the mid 
90s I think.  My analysis never stated that the primary holding 
action of the wing attachment fittings was due to friction.  That 
analysis shows that the wing attachment fitting, as designed, is not 
as strong as the spar when taken as a whole if clamping friction is 
not assumed.

That analysis shows that the WAF-to-wood bolt interface will fail 
before the spar fails if there is no clamping friction.  The 
bolt-to-wood reaction prior to localized failure is something like 70 
percent of the ultimate strength of the spar.   In my opinion, this a 
marginal design and can be improved with only minimal re-design.

In the standard KR design, the 3/16" mounting bolts do have a tensile 
component since they are in single shear, but the primary component 
of the load is shear.  A better design is to use one long bolt with a 
compression member between the WAF pairs instead of paired short 
bolts, placing the joint in a balance double shear.   This is my 
considered opinion as a professional engineer.

I do not remember any article that talked about actual load testing 
to failure of a KR spar.  If you can tell me where that is I would 
like to read it.  I do have the KR newsletters on CD but I do not remember it.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> WAF Bolt Sheer Load

[Donald Reid]

At 06:02 PM 6/9/2006, you wrote:
>This could be a good idea, if there was evidence of a problem, which
>there is NOT. Why is there an expectation that the WAF joint is a weak
>point?

Why accept something that is less than it can be?  If people were 
willing to belive that something can't be improved, then we would 
still be driving Ford Model "T"s.  A designer has to try and find a 
better way to do whatever the job is.

The KR wing attachment is not an optimal design.  It was copied 
directly for another, older, design and no thought was given to 
making it better.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Re: Another Epoxy & Hardener Technical Question

[Donald Reid]

At 12:12 AM 6/3/2006, you wrote:
>   I read tons of archived messages but I couldn't one that answers 
> my question.  If it has been asked before, I apologize.
>   The amount of hardener mixed in with the resin affects the pot 
> life of the epoxy.  All factors remain constant, more hardener 
> gives you less pot life, right?
>   Q1. Does the amount of hardener affect the strength of the epoxy mixture?
>   Q2. Does the amount of hardener affect the curing time of the 
> epoxy mixture?
>   Q3. What happens if you mix with wrong ratio of resin and 
> hardener called for by the manufacturer?
>
>   Thanks for you help.

Your assumption about pot life is incorrect.  Epoxy should be mixed 
as close to exactly as specified.  If the ratio is off by more than 
about 5 percent, the physical properties of the cured epoxy will be 
sub-standard.  Pot life is dependent upon the ambient temperature, 
the quantity of epoxy being mixed, or the hardener being used.

The chemical reaction will progress faster at higher 
temperatures.  The chemical reaction is exothermic and will make its 
own heat which can affect the cure time.  Some brands use different 
hardeners to get different pot life or allowable working temperature ranges.

If you want a quality product, you mix the epoxy exactly as the 
manufacturer specifies.  Anything else will reduce the strength or 
alter the properties in an bad way.  The two different components in 
epoxy combine chemically and the ratio must be very close or there is 
an un-reacted portion left over.

The chemical reaction is different for polyester based products.  The 
catalyst (methyl ethyl ketone)  causes the resin to form a series of 
long chemical chains.  More catalyst makes the reaction happen faster.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Spar wood

[Donald Reid]

At 11:15 PM 5/7/2006, you wrote:
>Hey guys,  Since I dont have a set of plans, can anybody tell me what  wood I
>would need to order to build a set of KR2S spars - The center ones, front
>and rear.   The only difference is that they will be 10 feet long  -  the
>outboard spars will be standard length.  I plan to build the  18% 
>new airfoil so
>will be 8" tall I believe.  I hope to order the wood for  the center 
>spars within
>the next month or two but need the info.  I have a  set of stock spars to get
>some of the measurements as far as spacing  from.   Thanks.

Have you done the engineering analysis to know what loading this spar 
will take?  You may be setting yourself up for trouble or you may end 
up with a spar that is over-built (and therefor a waste of 
weight).  This is not a good place to use a guess.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Ground Clearance again

[Donald Reid]

At 10:06 AM 5/4/2006, you wrote:
>Steven,
>  In my opinion... The average experimental seems to need
>about 7 to 8 inches of prop clearance, when the plane is level.
>There are lots of high time guys out there flying them with less than
>that, but that seems to keep the average guy out of trouble.  Bobby

If I remember correctly, certificated aircraft are supposed to have a 
minimum of 9 inches of clearance in level attitude when loaded to 
gross weight.  That is a pretty good number to aim for.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Tall KR builders

[Donald Reid]

At 09:03 AM 4/26/2006, you wrote:
>I think Matt is probably the only one building what amounts to a KR2s in a
>single seat just so he can fit. 6ft9in. 250lb
>
> > I think that if Mat Elder shows up you will be the second tallest.  I
> > believe he flies a four seat airplane so he can sit in the back seat and
> > have enough room between him and the rudder pedals.
> >

OK, he outweighs me by 15 pounds.  The height would be a match.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Two throttle controls?

[Donald Reid]

At 12:03 AM 4/24/2006, you wrote:
>Netters Is there any reason why one of those Dual input devices 
>could not be use
>dual mixture controls?  looks possible to me.  Of  course things can start to
>get crowded.
> > >
> > >A/C Spruce has a handy device in there catalog that allows you 
> to connect 2
> > >trottles to it for one output.  They even have a picture.  It 
> does not look
> > >all that complex.
> >
> > Even more simple, a Marvil-Schebler Carb has three holes in the
> > throttle lever arm.  I have connected the pilot's side throttle, with
> > friction lock, to the center hole, and the passenger's side throttle
> > to the outer hole.  There is only one mixture control and that is on
> > the pilot's side.

There are two things to consider for that.  On my MA-3, there is only 
one connection point for the mixture, so an intermediate linkage 
would need to be fabricated.  The other consideration is, would the 
passenger need to adjust mixture?  I certainly don't think so.  I 
also did not duplicate the carb heat control on the passenger 
side.  Again, I do not think that it is necessary.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Fly-In

[Donald Reid]

In just less than a month (May 18 through 21) there will be a Fly-In 
at Lumberton, North Carolina.  This will be their third year and they 
are trying very hard to make this into a significant event.  Their 
stated goal is to make Lumberton the third largest Fly-In in the 
US.  I will be there for the first time, not with my KR, which is 
still not ready, but as one of the two Fly-In photographers.  I hope 
that some of the KR network will be there so that we can meet.  I can 
guarantee that I will take "official" pictures of all the KRs that 
show up.  I can't guarantee that they will be published anywhere.

Details of the Fly-In are at
http://mafsac.com

If any of you make it there, I will be the tallest guy on the field 
and will have a load of camera gear.  Please introduce yourself and 
we can talk about KRs



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Removing Foam after glassing?

[Donald Reid]

At 04:51 PM 4/25/2006, you wrote:
>My understanding is the foam is completely non-structural, and by
>removing it, I could possibly save up to 20Lbs.
>Proposed method is to glue the foam in place, per plans, but apply duct
>tape over the foam between the spars and around the leading edge, glass
>the wing, then pop the foam loose, leaving the nicely shaped fibreglass
>behind.

The foam is most definitely structural.  It carries a 
significant  portion of the shear load from wing skin to the 
spar.  It resists the skin buckling when the wing bends.  It 
transfers localized stresses to help prevent punctures.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Two throttle controls?

[Donald Reid]

At 10:25 AM 4/22/2006, you wrote:
>Virgil:
>
>A/C Spruce has a handy device in there catalog that allows you to connect 2
>trottles to it for one output.  They even have a picture.  It does not look
>all that complex.

Even more simple, a Marvil-Schebler Carb has three holes in the 
throttle lever arm.  I have connected the pilot's side throttle, with 
friction lock, to the center hole, and the passenger's side throttle 
to the outer hole.  There is only one mixture control and that is on 
the pilot's side.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Stalls @ gross weights

[Donald Reid]

At 10:40 AM 3/18/2006, you wrote:
>I am surprised that a simple solution is always taken as an insult.
>If you are not familiar with the procedure for establishing
>airspeed limitations that GA uses, then dont take it
>as an insult, just admit it and then find out how it is
>done by the rest of aviation and stop guessing and probably get yourself and
>others in a possible jam.

You just set yourself up for an amazing amount of flame.  You implied 
that a very qualified engineer and KR pilot does not know something 
that simple.  The discussion thread was related to instrument 
uncertainty and as-built differences in experimental aircraft.  It is 
probably time for you to beat a hasty retreat because the abuse is 
about to begin.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Canopies

[Donald Reid]

At 05:50 AM 2/6/2006, you wrote:
>  I also find the Dragonfly style to be very
>desirable, but it is also very expensive.  And, unless you are really good
>at forming plastic, and have the equipment to do it, save yourself and don't
>even consider it to be an option.

I must agree with this opinion.  I tried to make a Dragonfly style 
canopy by drape molding and it was a total waste of time and 
money.  The best thing that I can say about it is that I did not burn 
down my shop during the attempt.  If I really could not find a 
reasonable source of a canopy, then I would consider two pieces of 
flat wrapped.  One curved around the front and attached to a canopy 
bow and the second wrapped over the top.  It does not look nearly as 
good but it is an option.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Spars

[Donald Reid]

At 07:23 AM 1/14/2006, you wrote:
>With the glues that we have today, like T-88, is scarfing really necessary?
>Would not just gluing on a cross member do just as well? I know that the
>woodworking purists will scoff at this, but T-88 won't come apart. If you
>were concerned about the contact area, you could put in a little wider cross
>member. I, personally, do not think that scarfing is any fun and find it
>most difficult to get a straight line.

Standard aircraft construction practices came about because they work 
and other methods don't work as well.  There are alternatives to 
scarfing that can be used on lightly-loaded, non-critical parts but 
they should not be used in a high-stress critical application.  My 
opinion is that if you don't want to do it right then you should 
consider taking up some other hobby.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Fiberglass laying

[Donald Reid]

At 10:13 AM 1/5/2006, you wrote:
>I bought some BID fiberglass today in a shop in Paris that sells all sorts
>of composites mainly for artists and designers. I was also looking for
>peel ply. The guy had never heard of it. When I explained the purpose, he
>showed me rolls of rigid plastic sheets (looking like old overhead
>projector slides). He said that's what his customers use when they want
>the cured surfaces to be smooth.
>
>That puzzles me. How come we don't do that? Is it because they fear
>trapped bubbles less than we do, or what?

That would be mylar or something similar.  I have gotten a roll at a 
local art supply house and used it for certain layups.  There are 
construction techniques that involve doing layups on the mylar sheet 
and then leaving it on until the epoxy has cured.  It will leave a 
very smooth surface.  Alex Strojnik has written at least one book on 
the method of making wing skins that way.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Aero Carb

[Donald Reid]

At 07:58 PM 12/20/2005, you wrote:
>Yes, it is a friction lock, but it does not seem that a carb should be
>closing the venturi, all by itself, even against some force.  My concern is
>that if I lock it down and then need to react to a situation, I won't be
>able to.

I would also recommend that you install a spring which will pull the 
throttle to something close to full if the cable becomes 
disconnected.  If and when the cable comes loose, you want to stay in 
the air until you are ready to shut off the mixture and land.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> aileron hinges.

[Donald Reid]

At 07:35 AM 12/5/2005, you wrote:
>I'm not an engineer or even an expert,  but how valid is static testing with
>no air load on the aileron.   Our operating environment has air moving over
>that service at up to 200 mph, which I would think would effect the outcome
>in serviceable hours.


I am an engineer and an expert on airfoils and I know a lot about 
materials, stress calculations, fatigue life and a few other 
engineering things.  A solid surface aluminum hinge is unconventional 
but perfectly safe.  The service life should be on the order of 
10,000 hours (my estimate only).  It will be much less likely to fail 
in service than an aluminum propeller and you would not think twice 
about flying behind one of those.





Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> aileron hinges.

[Donald Reid]

At 09:13 PM 12/5/2005, you wrote:
>Don,
>I have carefully read your website and trust your judgement as an educated
>builder.
>What do you think of the same general arrangement on a KR? Attatching an
>aluminum sheet? Or possibly a kevlar sheet?

It is a bad idea to do it with a composite sheet without a whole lot 
of testing.  What is the flexure lifetime.  The resin would probably 
fail before the fibers but how long?  I don't know and I don't have 
the data.  In addition, laminated construction is very weak in peal 
strength.  It would be difficult to design an all-laminate flexible 
hinge that does not depend on resistance to peal unless you use 
mechanical fastenings.  You could do it with an aluminum plate, but 
again, it would have to have mechanical fastenings and require 
additional testing.  Why would you want to change?



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> aileron hinges.

[Donald Reid]

>Wouldn't an aileron, that was hinged with a flexible aluminum plate, be
>more susceptible to flutter at the speeds the current crop of KRs are
>attaining?

Flutter is primarily a function of the natural frequency of 
vibration.  A stiffer system would increase the natural frequency so 
a plate hinge might in fact be less likely to flutter.  But on the 
other hand, I have never thought that much about it.  Composite 
construction does not lend itself to this type so I am not worried 
one way or the other.




Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> ANC-18

[Donald Reid]

At 11:36 PM 11/7/2005, you wrote:
>Can anyone tell me where on the FAA web site I can get ANC-18, or 
>alternative sites, and can anyone reccommend any good books on 
>wooden aircraft construction.

I have an original copy of ANC-5, -18, and -19.  I make high quality 
bound copies that I sell at just above my cost.  There are details 
available on my website.  I believe that EAA sells copies but they 
charge more than I do (shameless commercial commentary)



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Re: AS504x wings

[Donald Reid]

At 07:24 AM 11/9/2005, you wrote:
> >From the discussion then, I get the impression that the quarter cord
>figure is empirical - but pretty close to the calcutated figures for RAF48
>and AS504x wings.

The quarter chord location is not empirically derived.  It is located 
at 25 percent of the chord.  It is useful in aerodynamic calculations 
for a variety of reasons.  The aerodynamic center is also not 
empirically derived.  It is a real point in the airfoil and it is 
defined as the point at which the pitch moment is constant.  This is 
the twisting force that an airfoil generates as it generates 
lift.  It is typically a nose-down force.  A symmetrical airfoil will 
have a pitch moment of zero.  Airfoils with a trailing edge that are 
reflexed upwards can have a positive pitch moment and may be used in 
flying wings.

>I guess that the important thing in designing a wing is that the spar is
>as close as possible to the centre of lift, so as to minimise twisting
>forces inside the wing.

Minimum twisting forces in a wing will generally occur with a spar 
that is located somewhat behind the aerodynamic center.  With a 
typical airfoil, this is generally about 30-35 percent.

>I guess also that the most important consideration regarding CG is that it
>must never move aft of the center of lift, you want to ensure that if the
>fan stops pulling, then the plane will tend to dive rather than nose up
>into a stall.
>
>If there a rule of thumb for calculating safe CG?

The only real way to calculate this before flight testing is to 
determine the neutral stability point.  If the center of gravity is 
at the neutral stability point, a change in the pitch control force 
will result in a constant change in the angle of attack.  An airplane 
is generally neutral in roll stability; if you give it some roll 
force on the stick, it will roll at a nearly constant rate until you 
remove the roll force from the stick.  Neutral in pitch does exactly 
the same thing.  The farther forward the center of gravity is from 
the neutral stability point the more stable the aircraft in pitch.

For a conventional aircraft configuration, the neutral stability 
point will be somewhere between 30 and 40 percent of the Mean 
Aerodynamic Chord.  Your aft-most CG limit is then fixed at least 5 
percent in front of that point.  My own KR based design has a 
calculated neutral stability point at 34.5 percent.  Until flight 
testing is completed, my aft-most CG limit is 29 percent of the MAC.

If you want a rule-of-thumb and you have a conventional looking 
airplane then start with a CG of 20 percent and move the allowable 
range through flight testing in small increments.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> AS504x wings

[Donald Reid]

At 01:27 PM 11/7/2005, you wrote:
>I would like to see that reference, I would be
>surprised if the center of lift didn't move some with
>changes in AoA.

These last few posts have mixed a number of different aero terms.

The 1/4 chord location is located 0.25 times the chord back from the 
leading edge and on the chord line.  In x/c , y/c coordinates that 
means 0.25, 0.0

The aerodynamic center is the point at which the pitch moment is 
constant.  It is near the 1/4 chord location but generally a little 
behind it.  It can be above or below the chord line but it is 
generally near the chord line.  This is the point where all most all 
modern aero design is based.  It does not move to any significant 
degree over any angle of attack below stall.  On a symmetrical 
airfoil, the 1/4 chord is the aerodynamic center.

Based on my calculations, the aerodynamic center of the AS series in 
x/c , y/c coordinates is:
AS5045  0.2533, -0.0006
AS5046  0.2539, -0.0007
AS5048  0.2566, -0.0012
and for comparison, the RAF48 is 0.2528, -0.0005

The center of lift and center of pressure are older terms that mean a 
point at which the pitch moment is equal to zero.  These move with 
the angle of attack.  They are difficult to use in any real 
aeronautical calculation but they still show up in older reference books.




Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> W & B dilemma

[Donald Reid]

At 09:09 PM 10/31/2005, you wrote:
>Jerry and I have a dilemma.  Our WB gave us very conflicting results with
>each scenario that we performed.  It had Jerry weighing 35 pounds and me
>weighing 37 pounds different from the empty weight.
>
>You guys, WHO HAVE DONE THIS, what did you use to weigh your planes?  We are
>using 2 bathroom scales with a board over them under each wheel and one
>under the tail.  The tail weights are consistant and are reasonable, but the
>other ones are all over the place.

One thing that I have not seen in any of the other replies is that 
there must not be any side load on the wheels when you weight 
it.  You have to roll the plane back and forth a few inches several 
times when it is on the scales.  If you pick up a wing and then just 
set it on the scale there will be a friction side load applied to the 
scales that will not be measured as a weight.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Windshield

[Donald Reid]

At 08:38 AM 10/19/2005, you wrote:
>Dan Heath wrote:
>
> > My best advise to anyone thinking of forming their own windshield, is go
> > have as many Heineken as it takes to make you forget that thought.
>
>I too entertained thoughts of making my own canopy.  What got me off of that
>idea was Don Reid's comment "the best thing I can say about the many
>attempts to make my own canopy is that I never completely suceeded in
>burning my house down in the process", or something to that affect.

That is almost exactly what I said and it is true.  Making your own 
canopy with an oven and molded plexi is not something that anyone 
should want to try.  Uniform temperature is extremely important and I 
did not have it.  It is cheaper to buy one already made by someone 
who knows what they are doing.

On a different note, I am ready to put on the final paint on the 
fuselage bottom and I should get that done before the weather turns 
too cold.  The remainder of paint will come in the spring.  This 
winter will be finishing all of the little system stuff.  I am on a 
waiting list for a hanger and it looks promising that one will be 
available in the spring at the airport closest to me.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> steel tube fuselages

[Donald Reid]

At 01:28 PM 10/15/2005, you wrote:
>just to get a dicussion going. I have a hypothetical question to the 
>net and I'm sure it's been either done or thought about.
>  If one decided to mate a KR wing set to a truss type steel tube fuselage
>  how would one go about doing it?
>. snip
>How would one bolt the wing to fuselage attach fittings to the spar, 
>would you use the
>same bolt pattern as on the wing attach fittings or use 1/4 inch 
>bolts on center of the
>fitting 3 on one side of the 5/16 inch mounting bolt and 3 on the other side.
>I hope my question is clear enough

It would certainly not be difficult to design an attachment of this 
type but an on-line forum is not the correct place.   You need some 
engineering analysis, not just a "that looks about right" 
feeling.  Based on my analysis of the KR wing, if you took a KR outer 
wing panel and moved it to the root of a fuselage, 3 1/4 inch bolts 
through the wooden spar cap are not nearly enough unless there are 
large diameter load bearing bushings in the spar cap.

The minimum number of bolts that can be used to bolt a spar cap are 
4, and the diameter of the bolt or load bearing bushing in that case 
is  1/3 the thickness of the spar cap.  For example, if the spar cap 
is 3 inches thick, including any taper, you can design a fitting that 
will need only 4 bolts through the wood, but they must be 1 inch in 
diameter.  Since you would not want to use a bolt that large, they 
would be about 3/8 and they would pass through a bushing made out of 
aluminum that is 1 inch OD that is in the spar cap.

There are other designs that use a wooden cantilever spar bolted to a 
tubing fuselage, so yes it is do-able.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Virginia Regional Fly-In

[Donald Reid]

The Virginia Regional Fly-In will be this weekend, October 1st and 
2nd.  We had to cancel last year because of prolonged hurricane 
activity that kept us from getting the field ready, but in 2003 we 
had two KRs, I think they were Ken Wilhoit and Billy McFarlan.  Gary 
Hinkle has been there several times as well.  This year promises to 
have truly excellent weather in our part of the country so we expect 
a record turn-out.

Since I am the webmaster, webhost, and Fly-In photographer, there 
will always be pictures of any KRs posted on the site.

Details of the Fly-In are available in the link below.  It is the 
policy of our Fly-In to not charge admission to people flying in, 
unlike a lot of others.  After all, the planes ARE the show.

I will be there both days taking pictures so if you happen to see me, 
please say hello.  (Very tall and lots of camera gear)

BTW, we still need volunteers, especially to help with parking 
airplanes on Sunday.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA Regional Fly-in: http://vaeaa.org

KR> Weight

[Donald Reid]

At 09:37 AM 9/2/2005, you wrote:
>Can anybody tell me about the weight of the engine mounted his KR2S?

My O200 with cooling shroud,. magnetos. B & C alternator, no starter, 
and a 4 inch prop extension, weighed 213 pounds.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Control System

[Donald Reid]

At 12:13 PM 9/5/2005, you wrote:
>Has anyone got a design for a rod aileron control system, for KR2s?
>
>Peter


I do.  It can be seen in some of the pictures on my website.

If you want an Autocad drawing please contact me off network.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Hartford photo

[Donald Reid]

At 09:17 PM 7/27/2005, you wrote:
>My most memorable Hartford KR Get-together photo is at 
>http://home.hiwaay.net/~langford/050725175m.jpg . Looks like Dean 
>Cooper is in ground effect!  Jones was standing next to me (50 yards 
>further down the hangar row), and had good reason to duck!  Marty's 
>got nothing on this guy...

I don't want to sound like a party-pooper, but that looks to me like 
reckless endangerment.  If someone from the FAA were there or someone 
took this photo and used it in a formal complaint, it could mean a 
loss of license and large fine.  I think that this kind of thing is 
just not worth it.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Stalls

[Donald Reid]

At 08:26 PM 7/13/2005, you wrote:
>Dennis and netters
>The reason that some planes can "lift" a wing in slow flight while 
>others can't has to do with a long "arm" or simply the leverage that 
>the rudder has due to the length of the tailboom.


Not entirely true.  The more dihedral the plane has, the more 
pronounced the yaw/roll coupling (lift a wing with rudder) will 
be.  High wing have more effective dihedral than low wings due to the 
location of the center of gravity, so a KR looses a some of the 
potential for lifting a wing with rudder.

>  Although some of the trainers allow for use of the rudder alone to 
> lift a wing during slow flights and stalls, this is mainly done by 
> CFI's in training to build control confidence in the student so 
> that the student gets used to small inputs, and being smooth, not 
> because the rudder is the preferred control device.

Also not entirely true.  My father was a P47 pilot.  He has told me 
that they were taught to always use rudder to pick up a wing when 
they were slow.  In certain situations, the wing will stall abruptly 
toward the low wing when you try and lift it with ailerons 
alone.  For example, you can read Delmar Benjamin's book about his 
experiences with the GeeBee R1 replica.  In one of his early flights, 
it almost snap rolled on final approach when he tried to raise the 
wing with aileron.  He said that after that event, he used rudder to 
lift the wing in slow flight.




Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Mains for tri-gear

[Donald Reid]

At 11:11 PM 7/8/2005, you wrote:
>I just recently purchased a Sonori spring gear complete with axles,  wheels,
>brakes and good tires. The dimensions are the same as the grove design  for
>the KR with the exception of the spacing between the leg bends which  is only
>27". Does anyone have any experience mounting this gear on a KR? 
>Sure  want to
>use it as it only cost me $100.00 U.S..Needing some ideas.

That is too narrow to be used on a KR2, but there is a way that it might be 
used after modification. The gear could be cut diagonally between the 
bends.  The main support would be essentially the same and there would be a 
hole drilled at the end of the taper.  This hole would be used to attach 
the narrow end of the gear leg to a second pair of mounting 
brackets.  There is a picture of one like this in Tony Bingelis' "Sport 
Plane Construction Techniques" on page 247.  Since a Sonori is 
approximately the same weight as a stock KR2, the gear should be adequate.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> nylaflo brake lines

[Donald Reid]

At 03:50 PM 7/5/2005, you wrote:
>All,
>I repaired my brake line yesterday and I have to admit that the failure
>was partially my fault. When I took it apart I noticed that I had
>tightened the plastic furrel down so tight that it was squeezed up
>through the top around the tubing.

I have not used my brakes yet but there was something recommended in Sport 
Aviation years ago that I incorporated.  I have a small piece of brass 
tubing inside the nlyaflow (nice spelling) where the ferrule clamps down on 
the tubing.  It keeps the nylaflow from collapsing but lets the brake fluid 
go through.  I used a piece of the tubing from a ball point pen after all 
of the ink was cleaned out.  It was a perfect size.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Having a washer under the head

[Donald Reid]

At 01:21 PM 6/23/2005, you wrote:
>  At LEAST one thick washer, and as
>many as needed to allow visual inspection to confirm that the nut is
>torqued properly, not bottomed out on the threads.
>
>SEE AC43-13-1B, Section 7-37, which says maximum 1/8 inch of washers,
>but no reason stated.

The reason should be fairly obvious.  AN bolts come in 1/8" graduations of 
length.  If you need 1/8" (or more) of washers, then you can use the next 
shorter bolt.  With a standard AN lock or castle nut, if no more than three 
threads are showing above the top of the nut, then the bolt has not 
bottomed out.  Proper thread engagement is ensured if one thread is 
showing.  That differential is approximately the thickness of an AN washer.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Where To Start?

[Donald Reid]

At 07:23 PM 6/19/2005, you wrote:
>One question that I have found no answer for is has anyone
>tried to run hydraulic controls for all the systems i.e. rudder elevator
>etc?

This is a really bad idea since it adds complexity, weight, and a whole new 
set of failure modes.  Big airplanes use electro-hydraulic controls for a 
reason.  You do not want to fool with them.

As a general rule of airplane design, if something is done a certain way 
there is probably a good reason.  In the century of flight, people try lots 
of things.  The smart ones did not get killed and the dumb ones did.  This 
is the most basic form of evolution.

If you are going to try something new and creative, then you must be 
smarter and a better engineer than the people who went before you.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> To foam or not to foam.. that is my question

[Donald Reid]

At 11:22 AM 6/10/2005, you wrote:
>I plan on using 5.9oz carbon fiber to lay up the turtle deck. I need to know
>if I should use foam as a substrate (sandwich), or is it acceptable to just
>build a mold and lay it up over that withough any foam.   Is the foam going
>to add enough strength to offset the weight penality 2-3 lbs? Shouldn't the
>carbon be strong enough to stand on its own without "oil canning"?

I did something similar except it is glass and not carbon.  I made mine 
from three plies of glass and then added foam hoop stringers spaced about 8 
inches apart covered with an additional two plies of glass and a foam/glass 
bulkhead behind the baggage area.  I also have a foam/glass area right 
behind the canopy.  It is very strong and does not oilcan.

Photos are available on my site.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> 4130 steel

[Donald Reid]

At 03:38 PM 6/6/2005, you wrote:
>If I buy strips of 4130 steel of the correct thickness from Aircraft
>Spruce, can I use them as they are to make WAFs, or is there any treatment
>(other that surface treatment) that I must apply?

You would get the steel in a Normalized (N) condition.  After the milling 
process, the steel is raised to approximately 100 degrees F above its 
critical temperature and then allowed to cool in still air ( meaning 
slowly).  The critical temperature is where the steel is no longer 
magnetic.  It relieves the milling stresses and helps prevent subsequent 
failure.  My generic reference manual, Marks' Standard Handbook For 
Mechanical Engineers, does not list 4130, but the typical temperature for 
carbon steel is 1500-1700 degrees F.  Annealing temperature is typically 
lower by 100 to 500 degrees.

If you can hold the steel in your bare hand while you are making your 
part(s), then the you have not caused any significant heat related change 
in the mechanical properties of the steel.  If you do get it too hot to 
hold, then let it cool slowly in still air and it will be fine.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> ground effect and stall speed?

[Donald Reid]

At 05:57 PM 5/28/2005, you wrote:
>Does anybody know if ground effect lowers your stall speed?  I would think 
>so, at least some small amount, but I don't know for sure.  If so, how much?

Technically speaking, the stall speed decreases asymptotically to zero the 
closer you get to the ground but you will never see that in a practical 
case.  The coefficient of lift does not continue to increase at the same 
rate and positive sink rate means you eventually come down.  In the 
practical case, the stall speed will be as much as 1/2 the normal 
stall.  That is one reason that you can lift off so far behind the power 
curve and not be able to climb out.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> WAF application?

[Donald Reid]

At 11:55 AM 5/24/2005, you wrote:
>Ok i know the stub spar and main spar have like a 2" gap between (wood
>to wood).
>
>but would the strength be affected by butting the wood spar ends and
>moving the
>WAF outboard just enough to put the attach bolt thru the outer spar with
>a anti-crush spacer in the outboard
>spar?

It could be done that way, but not with the existing fittings.  The spacing 
would need to be changed.  The one other thing to consider it that the two 
pieces of spar should not be butted hard together.  There should be enough 
gap to ensure no wood-to-wood contact when the spar is loaded.  That 
condition would affect the stresses in the wood around the bolts.

Best option, keep what you have.  Next option is to do a re-design of the 
fittings.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Empty weight

[Donald Reid]

At 10:26 AM 5/11/2005, you wrote:
>I noticed that my WAFs'lightenigh holes are all 1/2" diameter, so I
>probably can increase these holes as per specs. Every little helps.

Please note that these holes are not to make the fitting lighter, but a 
part of the structural design of the fitting.  The graduated size is important.

Quoting from ANC-18, Design of Wood Aircraft Structures
"BEHAVIOR OF DISSIMILAR MATERIALS WORKING TOGETHER  When materials of 
different rigidities such as wood or metal fittings are fastened together 
... and are under high stress ... (such as) a long metal strap bolted to a 
wood spar flange for the purpose of taking the load out of the wood at a 
wing joint.  In order that the load be uniformly distributed among the 
bolts, the ratio of the stress to the modulus of elasticity should be the 
same for both materials at every point.  This may be approximated in 
practical structures by tapering the straps and the wood in such a manner 
that the average stress in each divided by its modulus of elasticity gives 
the same ratio."

This is a fancy engineering way of saying that the material in the metal 
fitting must be tapered as it progresses away from the removable 
bolt.  That is the point where the load is applied to each fitting.

It is more difficult to taper the material in thickness than it is to taper 
it in equivalent width.  That is why the holes increase in size from the 
outside to the inside.   The material that is left then decreases toward 
the unloaded end of the fitting.  The holes should be sized as called in 
the plans to make the correct fitting.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> engines

[Donald Reid]

At 11:00 PM 5/11/2005, you wrote:
>Speaking of certified engines, there is one gotcha I learned about that you
>need to be aware of if you use one.
>
>When you use a certified engine in an experimental you are required to
>comply with all the A.D.s.


This is not correct.  Your DAR was mistaken.  When a certificated engine is 
installed in an experimental aircraft, ADs and service bulletins do not 
need to be complied with.

There is one exception to this general rule and that is when a previously 
certificated engine is removed from an experimental and re-installed in a 
certificated airplane.  In this case, all ADs must be in compliance.

If your DAR raised (or raises) the issue, all you have to do is remove the 
data plate.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> engines

[Donald Reid]

At 09:45 AM 5/12/2005, you wrote:
>The application of the rules have changed with regards to certified 
>engines in experimentals.  They used to be exempt from Airworthyness 
>Directives, but now the FAA has chosen to enforce the ADs. (...snip...)  A 
>certified engine on an experiemental is now required to comply with 
>ADs.  Not really a change in regulation by the FAA, but instead is a 
>change in the interpretation of the regulations.

Could this be a regional interpretation?  Can anyone else comment?

>Having said that, the vast majority of ADs exist for safety reasons and 
>are based on long term experience with failure of that engine or part.  It 
>is usually in your best interest to install the applicable ADs anyway.

I could not agree more.

>Here's where it gets into some of the nits that people will undoubtedly 
>want to pick.  If you are using a certified part, the ADs apply.  For 
>instance, many of the dual ignition revmaster engines use the Bendix 
>single drive dual magneto.  If that magneto is the same part number as the 
>ones on a certified engine, or the serial number falls into the range of 
>serial numbers for that type for which an AD has been issued, that AD also 
>applies to that magneto on the Revmaster engine.
>
>OK, the question was posed earlier about building your own engine using a 
>Continental crank and case, but Chevy pistons.  In this example, any AD 
>that applies to the crank and case would apply.  Any AD that applies to 
>the piston, would not.

However, as soon as you install a non-certificated part on a certificated 
engine without proper paperwork (such as Form 337 or STC), the original 
certification becomes invalid if it is used in a certificated 
application.  A non-certificated engine should not need to comply with the 
requirements of certification.

Simple solution, remove the original data plate and install your 
own.  Comply with the ADs and service bulletins as you see fit.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Inspection hatch, tail section

[Donald Reid]

At 11:41 AM 5/8/2005, you wrote:
>I will have to make one or several inspection hatches on my tail section,
>for the following reasons:
>1 - I need to replace the elevator cables;
>2 - I need to remove the tail wheel spring;
>3 - I need to be able to inspect the rudder and elevator hinges nuts.

I have one access hole under the stab that is about 4" tall by 6" long. a 
removable section at the back of the turtleback, and inspection ports at 
the top and bottom of the elevator horns.  These are 2" in diameter and are 
will be covered with recessed plexiglass covers so that I can see the 
horns.  There are pictures of most of this on my web site.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Rivet question

[Donald Reid]

At 12:56 AM 5/4/2005, you wrote:
>Hello,
>
> I am about to cut my forward deck off and install piano hinges so 
> that I can make it removable. What kind of rivets are recommended to 
> connect the piano hinge to the fiberglass? I prefer a rivet that has a 
> low profile. Any help is greatly appreciated.

I used 1/8 inch countersunk with 1 inch center-to-center on my cowling.  I 
have about 8 plies of 5 oz glass at the rivet joint to reinforce the 
joint.  You can squeeze the rivets or put the bucking bar on the machine 
head (the outside) and drive the shop head (the inside) with a small hammer.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Is it really a RAF 48

[Donald Reid]

At 07:24 AM 5/4/2005, you wrote:
>Something puzzles me. I found by chance, over the Internet, a 'ribs
>generator' program, designed for radio-controlled models, wih more than a
>thousand profiles available. You just enter the profile type, the chord of
>the first rib, the chord of the last rib, and the number of ribs, and
>voila! You get a PDF file that goes to your printer, with "assembly marks"
>to help you glue the paper sheets together.
>
>I used it to make a RAF 48 profile, with a 48" chord, as per KR2 specs.
>The trouble is, what I get is different from the KR2 Scale 1 drawing. The
>KR2 profile is slightly thicker.

A long time ago, I measured the as-drawn RAF and compared it with the 
as-published data and I remember that they do not agree exactly.  The paper 
may have changed dimension and/or the copying process may not be a true 
one-to-one.  Small differences can be because of the way the smooth line 
joining coordinate points is generated.  The software uses a mathematical 
spline fit and the paper version used manual drafting tools.  It is also 
possible that slightly different coordinate data was used to generate the 
different versions.

Unless the differences are significant, the flying differences will be 
inconsequential.




Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> WAF

[Donald Reid]

At 05:12 PM 5/4/2005, you wrote:


>   In spite of using the WAF drilling the main spar I missed a little
>bit. Is it permissible to use T88 and a 3/16 wood dowl to plug the
>mistake or do I have to make a new spar?

That is an acceptable practice.  Use a hardwood dowel with plenty of epoxy.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> WAF

[Donald Reid]

At 11:30 PM 5/4/2005, you wrote:
>  My personal feeling without seeing how far the hole was
>missed is that it MAY be perfectly adequate to repair the hole by filling it
>with epoxy (don't know about the dowel with the grain in the completely
>wrong direction).

This is a bad idea.  Epoxy is not as strong in compression as the wood.  It 
would tend to deform and displace which would allow the bolt to move.


>One thing I would look at is what side of the hole will
>the repair be on?  I would think that if you missed along the grain instead
>of accross it that would be better.

This is immaterial.  The strength from a properly designed wooden spar does 
not depend on the grain orientation.  The strength depends on the 
longitudinal fibers.

The bolted joint in a wooden structure transfers the load into the wood by 
compression.  The force acting on the bolt pushes against the wood 
fibers.  As long as the applied force times the area being compressed is 
less than the allowable compressive strength of the wood, the joint is good.

In the case of a KR main wing attachment fitting, it also acceptable to 
drill certain (meaning only the correct ones) to 1/4 inch.  You can contact 
me off the KR network and I will provide appropriate reference 
material.  If it is done wrong, the attachment will be weaker.  Done right, 
it will be stronger.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> WAF

[Donald Reid]

At 11:01 AM 5/5/2005, you wrote:
>You state that the strengthof a properly designed wooden spar does not
>depend on the grain orientation.  I believe this is missleading, would
>you use wood that had a splope on th grain of 1 to 3 or 1 to 5 or 1 to
>20?.
>Jim

In the previous note, the context implied grain defined by growth 
rings.  The slope criteria is based on the longitudinal orientation of the 
wood fibers.  They have to run the length of the spar within the allowable 
slope.  The growth ring orientation for aircraft use is typically known as 
quarter-sawed, meaning the growth rings are more-or-less parallel to the 
horizontal in a tall slender board.  These two are very much related and 
sometimes confusing.  It is much easier to show with sketches than say with 
words.

A strength of a properly designed spar does not depend on the grain 
orientation of the growth rings, only on the fiber orientation.  The 
orientation of the growth rings does have a direct effect on the 
dimensional stability with changes in temperature and humidity.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> HVLP Paint

[Donald Reid]

I checked the KR archives about HVLP painting and most of the recent 
comments were about a discount gun.  I think that I would like something 
better.

Does anyone have any experience with a Wagner Softspray 2600?  It comes in 
a complete set, gun, hose, and blower. The list price is approximately $500.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Flipping the fuselage

[Donald Reid]

I flipped my fuselage today to do the surface prep and final paint on the 
bottom.  It will be upside down for about a month until the bottom is 
complete through final paint.  The weather was bad so I did not take very 
many pictures but I will add more when it gets turned over.

My flipping rig is similar to others I have seen on some of the KR web 
pages, but I made mine wider than most.  Mine is attached at the main spar 
with the wing attachment fittings and some brackets that I welded up out of 
scrap.  It is also attached to the fire wall and has lots of bracing.

I had a total of nine people (and my wife watching the show).  If I add 
wheels to the top (which is now on the ground) of the structure, it can be 
done with as few as four or five.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Wing tips

[Donald Reid]

At 09:28 AM 4/25/2005, you wrote:

>Does any one know where I can find information on effectiveness or 
>efficiency of wing tips? Is there a consensus on the best wing tip for the 
>KR2S? Any test results? Does the wing section make a difference for the 
>best tip?

I don't have the reference in front of me, but when you combine simple to 
build and efficiency the best is probably a triangular extension that is 
approximately as long as the tip chord.  The outer end of the extension has 
the same profile as the tip airfoil but it is only a few inches 
long.  Steve Whitman used them on his later designs.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Re:wing area

[Donald Reid]

At 10:14 PM 2/16/2005, you wrote:

> >
> > >I figured the area as flat
> > >plate of the wing dimensions. Am I doing something wrong or is this  a
> > >case of the spec's not being correct???
> >
> > Try including the portion of the wing in the fuselage.
> >
>That would add about 12sq. ft. but I do not picture that as to be
>included as wing area. I believed that wing area was that portion of the
>aircraft that had an  airfoil. If my number would be accurate then wing
>loading numbers would increase.
> Some how I don't feel like I can be right after all the 78 to 80
>sq. ft. number has been used for 30 years.
>Thanks - Joe Horton

The fuselage contributes lift approximately equal to that which would be 
seen from a continuous wing.  Just extrapolate the wing through the 
fuselage and add in this as wing area.  This is found any number of 
reference books on aeronautical engineering.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> question about airfoils ??

[Donald Reid]

At 11:13 AM 2/9/2005, you wrote:
>I have a question or two about airfoils.
>The other question is i know the bonanza, malibu, rv-3,4,6,7,8, venture
>egg and many other fast planes use similar airfoils:
>(form http://www.aae.uiuc.edu/m-selig/ads/aircraft.html)
>
>NACA 23016.5  Bonanza
>NACA 23015 Malibu
>NACA 23013.5  RV
>NACA 23017Questair Venture
>NACA 23014Cessna 550 Citation Bravo
>
>
>Are these planes fast due to the aifoils or the HUGE engine pulling them?

I have recently completed a Master's Degree in Engineering.  My thesis was 
on airfoil design and analysis.  I have spent several years studying 
airfoils.  It is my opinion that the NACA 23 series is not a good choice 
for an airplane.

Its one good point is a low pitching moment.  It has a sharp stall and a 
drag coefficient that is not particularly good.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> To laminate or not ...

[Donald Reid]

At 10:34 PM 2/9/2005, you wrote:
>Donald Reid wrote:
> >
> > You do NOT want to make spar caps out of plywood.  In the FAA
> > reference,  they are talking about laminating using with the wood
> > fibers oriented along the length of the spar.  The grain may be
> > oriented in a variety of different ways in spar lamination, but  the
> > wood fibers must run the length of the spar.
>
>Again, there was never any discussion of using plywood for spar caps.

That is incorrect.  The letter that prompted my response had the statement 
that a spar made out of stacks of 5 ply would be bulletproof.  That was a 
comment by someone who does not have all of the information necessary to 
make a sound judgement concerning airplane design.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> To laminate or not ...

[Donald Reid]

At 08:07 PM 2/8/2005, you wrote:
> >From the FAA A.C. 43.13 (You have read the FAA bible, havn't you?):
>
>1-43. REPLACING SOLID TYPE SPARS WITH LAMINATED TYPE SPARS
>Solid spars may be replaced with laminated spars or vice versa, provided the
>material is of the same high quality.
>
>There is also supposedly excellent book on wood aircraft design and
>construction that someone mentioned a while back (Don Reid?).

> > How about making up wing spar caps out of several laminations of ply?
> > As we are taught, a good scarf makes for any length you like without
> > any strength compromise.
>
> > Using 5 ply must surely result in a bullet proof spar?


The book is ANC-18, Design of Wood Aircraft Structures.  It is the bible of 
wooden airplane design.

You do NOT want to make spar caps out of plywood.  In the FAA 
reference,  they are talking about laminating using with the wood fibers 
oriented along the length of the spar.  The grain may be oriented in a 
variety of different ways in spar lamination, but  the wood fibers must run 
the length of the spar.

There is a lot of science involved in structural design and it is certainly 
one area in which you do not want to do something stupid



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Exhaust

[Donald Reid]

At 04:10 PM 1/26/2005, you wrote:
>Are there any rules of thumb of scientific formulas that would determine 
>the length that the exhaust tubes should extend below the belly of the 
>airplane.

If at all possible, the exhaust should not extend beyond the surface of the 
plane.  Any protrusion will be a source of drag.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> bad news from the DAR

[Donald Reid]

At 06:54 PM 1/16/2005, you wrote:
>Group,
>
>I have had an unpleasant conversation with my local DAR. He stated that 
>once an amateur plane is registered, that builder is the only person that 
>can have the repairman's certificate for that plane.

It is a correct statement that one experimental can have one person with a 
repairman's certificate.  That does not mean that you can't do your own 
work on an experimental that you bought from someone else.  You can still 
do your own work but you will need to have either an A or the holder of 
the repairman's certificate do the annual and that is all.

This is the way that it has been since the experimental regs can into being 
in the 50s.




Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Gear leg junction

[Donald Reid]

At 05:56 AM 1/11/2005, you wrote:
>HI All,
>I've been glassing the underside of my wing stubs and the inside of my 
>wing tanks today, wow that vinyl ester is awful to work with (sticky).
>I have a question about where my Diehl type gear legs enter the stub. I'll 
>need to fair the legs in a bit, Do most make these fairings removable or 
>are they normally glassed to the leg and the bottom skin of the stub and 
>left as a permanent fixture??

My gear legs is similar to the Diehl and I made the fairings 
semi-removable.  I put a layer of duct tape on the wing and gear leg, then 
added foam and modeling clay to shape.  This was covered with three-four 
plys of glass.  After it cured, I cut the fairing along the trailing edge 
and removed it.

After it was trimmed to shape I "glued" it back on with bath tub 
caulk.  Then I used dry micro to blend the fairing in to the wing and gear 
surface.  I left a joint line between the fairing and the dry micro so that 
it will not damage the paint if I have to remove it later.

The duct tape leaves a small gap around the leg and the glass can flex and 
not crack.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Mold release

[Donald Reid]

At 01:07 PM 12/18/2004, you wrote:

>On Sat, 18 Dec 2004 12:06:20 -0500 "Jack Cooper"
> writes:
> > I was looking in Wicks catalog for mold release in planning to make
> > cowling from Marks cowling molds.
>
>You should be able to substitute a good floor wax with carnuba for the
>parting agent.  The Mold Release is Poly Vinyl Alcohol (PVA).  A quart
>should be enough to do several cowlings.  Wax the mold up good, then
>paint the inside with PVA.


Hair spray is supposed to work in leu of PVA



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> spars

[Donald Reid]

Every few years, we go through a long thread of discussion about spar 
re-design.  In this recent set, the one thing that is apparent is that the 
people talking about making major changes in the spar do not have any 
training in structural design.  This is not an area where you design by 
eye-ball engineering.  You can NOT say "well, that looks about right" and 
expect to have an acceptable product.

Ken Rand and Stu Robinson where not experts in airplane structures, but 
they did not need to be.  They copied an existing design and did not screw 
around with it.

The only potential good result that I can see coming from this recent set 
of discussions is that most of the planes will never be finished.  They 
will languish in a shop or hanger for years, with occasional periods of 
unfruitful effort by an increasingly discouraged builder.  The unfinished 
project will finally be sold to some unsuspecting potential pilot and so on 
and so on and so on.

If you do not know what you are doing, then DON'T DO IT.  Built 
more-or-less to plans, the KR wing structure is acceptable.  It is not (as 
someone recently implied) perfect but it is good enough.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> spar carbon fiber

[Donald Reid]

At 05:42 PM 12/3/2004, you wrote:
>Enough about spars already!!! this has been flogged a thousand times.
>There must be a structural engineer out there somewhere who would be only
>too happy to answer any questions about this issue.

I am a licensed professional engineer and I gave my short answer 
yesterday.  To repeat: "If you don't know what you are doing, don't do it."

This is not the correct forum to design a critical wing structure.  Most of 
the ideas that have been proposed have been anywhere from silly to dangerous.

One more time: "If you don't know what you are doing, don't do it."



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> New Website Address

[Donald Reid]

I recently changed my e'mail address and I have just finished changing over 
my KR website to a new site.  There is no change in the content but those 
of you who have bookmarked the site may want to change.

I can be found at http://aerofoilengineering.com/KR/KR2XL.htm



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://aerofoilengineering.com

KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm
Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Don Reid

[Donald Reid]

At 02:02 AM 11/8/2004, you wrote:
>Hi Don
>
>With reference to the "Specs and Mods" comment on your web site:
>
>In the narrative you mention a stretch of 5" fwd and 6" aft for a total
>of 11" over the KR2S - thus a new length of 16'11".
>
>Your root chord is 4" greater (48 to 52) so maybe another inch or so in
>the distance between the spars and thus the overall length - so maybe a
>total of 17'.
>
>In the table comparing the KR2 /KR2S /KR2XL you give a length of 18'6"
>for your airplane.
>
>I am missing something here.

There is no increase/change in the distance between the spars.  I added in 
front of the main spar and behind the rear spar.  What I said that I added 
over and above the KR2S is accurate.

Without getting out the plans and looking at all of the dimensions, I can't 
tell you where the overall length came from.  In addition, the published KR 
dimensions are based on a "stock" KR with a VW engine.  There are also 
discrepancies in plan dimensions versus literature dimensions.

My final length is actually somewhat longer than I originally planned.

I did a weight and balance before making the engine mount so that the 
balance would be correct without ballast.  I have an O-200 without a 
starter and a very small alternator.  My engine weight is approximately the 
same as a heavy VW and less than a Corvair.  With all the mods, the engine 
mount is longer than anticipated.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Don Reid

[Donald Reid]

I want to apologize to the KR net for the previous post.  I did not realize 
that the question came over the net,  I assumed that it was directed 
specifically to me.  I responded as if it were a private conversation.

Please refer to the KR network rules that Mark Langford has published.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Don Reid

[Donald Reid]

At 08:50 AM 11/5/2004, you wrote:

>-Original Message-
>
>Don
>
>Can teel us why you went for a longer chord?
>
>What are the advanages you gained and at what cost, proformance wise?

My KR based plane was designed for a gross of 1450 pounds.  I wanted to 
keep approximately the same wing loading.  The plans built KR 2 has a wing 
loading of about 11 lb/ft^2 and the 2S is a little higher.  Mine will be 
14.5 lb/ft^2.  I also increased the span so that the span loading would 
also be comparable.

I finalized the design before I really started studying airfoil design and 
I simply picked one of the best NACA airfoils.  If I were to do it all 
over, I would design my own airfoil to meet my needs.  The NACA 747a315 
that I picked has a reasonably low drag, gentle stall, is resistant to bug 
debris, and has an extremely low pitch moment.

Most airfoils have a higher (more negative) pitch moment.  This must be 
counteracted with additional download at the tail.  This download is a 
negative lift that acts just like the plane has a higher gross weight.  The 
low drag and negligible pitch moment will result in a low overall 
drag.  That is, a plane with wing that has a low drag coefficient but a 
high pitch moment can have a higher overall drag than one with a higher 
drag and lower pitch.

I think that the performance will be comparable.  I am also spending a lot 
of time with drag reduction by surface finish, tolerance of gaps and part 
fit, and engine cooling, among others.  If I do it right, I hope that I 
will be able to keep up with any KR.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> GPSMAP 296 @ Discount prices (AC Spruce)

[Donald Reid]

At 06:25 PM 11/4/2004, you wrote:
>Now why in the hell would I ever want to buy ANY THING from A/S again 
>after a cheap shot like this. Bill Starrs

Why is it a cheap shot?  Garmin is making the rules if you want to sell 
their products.  If Garmin says no discounts, then that is their 
prerogative.  A retail business will follow those rules or loose the rights 
to resell the product.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> New email address

[Donald Reid]

For those of you who might care.  I have a new address.  I will be changing 
my web site address sometime later.



Don Reid  -  donreid "at" peoplepc.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> the heartbreak of Spraylat

[Donald Reid]

At 07:57 PM 10/29/2004, you wrote:
>NetHeads,
>
>I've spent 4 or 5 hours so far, and expect to spend many more, peeling the
>Spraylat off my canopy.Big Snip
>Anybody with good ideas as to how to make this bearable is welcome to
>enlighten me, but right now I'm waiting 'till Tuesday when UPS can bring me
>some Spraylat to put on top of this mess...

Have you tried a little WD-40?  I have never had to use it on Plexi, but it 
works great for removing adhesive from plastic.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> KR 3

[Donald Reid]

At 10:00 PM 10/20/2004, you wrote:

>Don Reid has some information on his site...
>
>http://users.erols.com/donreid/sportaviation/Kr77-8.HTM
>
>He also seems to be the foremost authority based on the posts he's made in
>the archives...until he writes, I hope this link helps.

I have some pictures of the KR3 and KR1B motor glider on my site but I am 
hardly the authority.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Composite Tanks

[Donald Reid]

At 01:33 PM 10/12/2004, you wrote:

>You guys building composite tanks:
>
>How are you routing the fuel lines through the tank sides?  Are you 
>drilling a hole, floxing, then using an AN fitting, or just running a hard 
>line though a hole and floxing the whole mess in place.

I started with an aluminum welding flange, Aircraft Spruce part number 
AN867-3 with a finger strainer, AC Spruce part number 05-17700.  Then 
fittings as necessary.

I drilled about 6 small holes in the flange, bedded it in place with flox 
against the tank wall, and the put a layer of glass over it.  It works 
extremely well.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Depleated Uranium (Lead)

[Donald Reid]

At 02:14 PM 10/16/2004, you wrote:
>  I
>have a hand time believing these materials are one and the same and think I
>would be getting another source of information to further investigate this
>little item.
>Doug Rupert
>
>Did you know that Lead is Depleated Uranium!!!

This is NOT KR related and the thread should be dropped but what the 
hell.  Most of you should delete this message unread.  Those who care about 
isotopic trivia can read on.

Speaking in my capacity as a Nuclear Engineer, the person who made the 
erroneous claim that lead is depleted uranium is really confused.  Depleted 
uranium is the material left over when natural Uranium is refined into 
either nuclear fuel or weapons grade Uranium.

Natural uranium is made up of two different  isotopes.  An isotope is a 
element with the same number of protons but a different number of neutrons.

Natural Uranium is made up of approximately 99.3 percent U-238 and 0.7 
percent U-235.  Nuclear reactors generally use Uranium that is enriched to 
approximately 4 percent U-235.  Weapons grade Uranium (the stuff that can 
make a really loud boom) is approximately 95-99 percent U-235.  The 
left-over material from the enrichment process is called depleted Uranium 
and it is almost exclusively U-238.  It has excellent mechanical and 
refractory (high temperature) properties and it is extremely dense.

Uranium is naturally radioactive and undergoes decay to different daughter 
elements and their isotopes.  I will not go through the full decay scheme, 
but the end result of the decay chain is lead, which is stable.

Lead is not depleted Uranium but it does come from Uranium decay.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Depleated Uranium (Lead)

[Donald Reid]

At 02:14 PM 10/16/2004, you wrote:
>  I
>have a hand time believing these materials are one and the same and think I
>would be getting another source of information to further investigate this
>little item.
>Doug Rupert
>
>Did you know that Lead is Depleated Uranium!!!

This is NOT KR related and the thread should be dropped but what the 
hell.  Most of you should delete this message unread.  Those who care about 
isotopic trivia can read on.

Speaking in my capacity as a Nuclear Engineer, the person who made the 
erroneous claim that lead is depleted uranium is really confused.  Depleted 
uranium is the material left over when natural Uranium is refined into 
either nuclear fuel or weapons grade Uranium.

Natural uranium is made up of two different  isotopes.  An isotope is a 
element with the same number of protons but a different number of neutrons.

Natural Uranium is made up of approximately 99.3 percent U-238 and 0.7 
percent U-235.  Nuclear reactors generally use Uranium that is enriched to 
approximately 4 percent U-235.  Weapons grade Uranium (the stuff that can 
make a really loud boom) is approximately 95-99 percent U-235.  The 
left-over material from the enrichment process is called depleted Uranium 
and it is almost exclusively U-238.  It has excellent mechanical and 
refractory (high temperature) properties and it is extremely dense.

Uranium is naturally radioactive and undergoes decay to different daughter 
elements and their isotopes.  I will not go through the full decay scheme, 
but the end result of the decay chain is lead, which is stable.

Lead is not depleted Uranium but it does come from Uranium decay.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Aeroelasticity

[Donald Reid]

At 01:52 PM 10/10/2004, you wrote:
>Hi frindes ..hope all of you are fine and and well ...these quistion are
>very important for me ,the reson is because I did not fly any kr2s in whall
>my life ...ok  my quistions  are :
>
>-1  Do we have to mass balance the control surfaces?

The short answer is Yes.  The longer answer is that ailerons MUST be 
balanced, elevators can be balanced, and rudders are not really a concern.

>-2 has any body encouter any flutter or unusual viprations at high speed ?

Supposedly, one KR based based plane broke apart during a high speed run 
and it is believed that a mass balance broke off of one aileron and it went 
into flutter.  This happened at one of the gathers back in the 80's.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> G limit

[Donald Reid]

At 11:42 AM 9/25/2004, you wrote:
>Dunno Wolfgang but it's a commonly quoted rule of thumb.
>
>
>Following from an earlier reply, how about a 12000lb Kingair that 
>increases weight by 100lbs - the load factor may change in the second 
>decimal, but NOT BY 1G.

The 100 pound increase = 1 G reduction in load that has been thrown out is 
an approximation for a KR built to plans.

In round numbers, a 800-850 pound KR should be able to take 7 Gs.  Of that 
gross weight, approximately 700 pounds is being supported by the wings and 
contributes to the bending moment on the wings.  If the fuselage weight 
increases by 100 pounds, the wings are now supporting 800 pounds.  If the 
wing structure is unchanged, the ultimate load factor will decrease by 
approximately 1 G.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> G limit

[Donald Reid]

At 12:33 PM 9/29/2004, you wrote:
>I've just decided I don't trust the Marcy analysis.  When he did it, he
>assumed the section of the wing inside the fuselage was producing lift just
>like the stub wings do.  That means that the lift produced by the outer
>wings is undercalculated and therefore the bending moment numbers he
>calculated are too low.

This is a standard assumption in the wing structure analysis, but you 
didn't understand what he meant.  The fuselage generates lift.  You simply 
calculate the wing area that would exist if the fuselage were not there and 
that is the assumed total lift of the wing/fuselage combination.  The 
bending moment on the wing is outboard of the fuselage.  The total lift is 
applied to the wing outboard of the fuselage and will make the calculation 
slightly conservative.

Making the fuselage wider, provided the wing panel length outboard of the 
fuselage, will not make the wing any weaker.  It will be unaffected.  It is 
the length outboard of the fuselage.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> sport aviation magazines on the kr

[Donald Reid]

At 05:13 PM 8/28/2004, you wrote:
>just go too the eaa home site type  aircraft you want. all so 23 articles on
>the Kr 1. you can get old articles for 5 bucks but we have some now it be 
>nice
>to have all of them on line.

I have most of the Sport Aviation articles posted on my KR website.  Just 
follow the link below.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Fuel tanks

[Donald Reid]

At 08:08 AM 8/10/2004, you wrote:
>   For best chemical resistance, recommend that you use vinyl ester resin 
> for the fuel tank construction.  Epoxy will work ok as long as you only 
> use aviation grade 100 octane LL fuel.  Automotive fuels may contain 
> alcohol and aromatic additives that will attack the epoxy.  Vinyl ester 
> resin is not susceptible to chemical attack by automotive fuels.

It is a common misconception that autofuel will degrade epoxy resin.  This 
is not necessarily so.  I prepared two sample coupons of Last-A-Foam and 
EZ-Poxy.  One coupon was saved as a control.

One half of the test coupon was fully submerged in autogas and the other 
half was not.  This coupon remained in a sealed container for over four 
years with absolutely no degradation.  There was no loss of strength, there 
was no sediment, and there was no discoloration of the gasoline.  After the 
coupon was removed and dried off, it was impossible to tell the difference 
between it and its control coupon.

The two things that must be done to ensure a chemically resistant gas tank 
is to have the mixture ratio correct and completely mixed.  If your 
resin/hardener ratio is off, there will be an uncured component in the 
final epoxy matrix.  It can dissolve in an solvent.  The same is true if 
you do not mix the components sufficiently.

Epoxy will work with autogas but your quality control is important.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Aircraft Spruce

[Donald Reid]

I have to add my own comments on Aircraft Spruce.  I have had minimal 
problems with them over a eleven year period, all but two happened shortly 
after they bought Alexander's Aircraft in Atlanta and turned it into A/C 
Spruce East.

In one order of wood, they transposed a 3 and a 4 and sent me 4 pieces of 
spruce that were 3 feet long, instead of 3 that were 4 feet long.  They 
made good on the mistake and I got to keep what I did not order.

I ordered bendable capacitance level probes and they sent me 
non-bendable.  The return/exchange process was painless and no cost to me.

I ordered the wrong exhaust gas probes (my fault) and again, the exchange 
process was painless.

The majority of the problems that had during the 6 months to one year 
period after they opened the east coast office.  That was a frustrating 
time, because I had been dealing with Alexander's and they were 
perfect.  The transition was rocky but they made good on all of the orders 
and eventually gave me a one-time discount as a way to say that they were 
sorry about the mess.

I have been pleased with the service that I have received from Aircraft 
Spruce.  I have no hesitation in buying more material from them.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org

KR> Aircraft Spruce

[Donald Reid]

I have to add my own comments on Aircraft Spruce.  I have had minimal 
problems with them over a eleven year period, all but two happened shortly 
after they bought Alexander's Aircraft in Atlanta and turned it into A/C 
Spruce East.

In one order of wood, they transposed a 3 and a 4 and sent me 4 pieces of 
spruce that were 3 feet long, instead of 3 that were 4 feet long.  They 
made good on the mistake and I got to keep what I did not order.

I ordered bendable capacitance level probes and they sent me 
non-bendable.  The return/exchange process was painless and no cost to me.

I ordered the wrong exhaust gas probes (my fault) and again, the exchange 
process was painless.

The majority of the problems that had during the 6 months to one year 
period after they opened the east coast office.  That was a frustrating 
time, because I had been dealing with Alexander's and they were 
perfect.  The transition was rocky but they made good on all of the orders 
and eventually gave me a one-time discount as a way to say that they were 
sorry about the mess.

I have been pleased with the service that I have received from Aircraft 
Spruce.  I have no hesitation in buying more material from them.



Don Reid  -  donreid "at" erols.com
Bumpass, Va

Visit my web sites at:

AeroFoil, a 2-D Airfoil Design And Analysis Computer Program:
http://www.eaa231.org/AeroFoil/index.htm

KR2XL construction: http://users.erols.com/donreid/kr_page.htm
Aviation Surplus: http://users.erols.com/donreid/Airparts.htm
EAA Chapter 231: http://eaa231.org
Ultralights: http://usua250.org
VA EAA State Fly-in: http://vaeaa.org