KR> flying to Mexico and points south
Jeff; When I lived in San Antonio I actually had genuine invitations from pilots and experimenters down in Guadalajara, Mexico to fly down there. In my 65 MPH Pietenpol! They would be thrilled to see experimentals down there and I'm sure you would be treated very well (as Colin Hales is finding as he makes his way across countries on the other side of the world). >From Los Alamos, take up a course of about 170* and 1,050 miles later, you'll >be in Guadalajara ;o) From there, it's an easy day-trip over to Puerto >Vallarta (125 mi) if you want some sun and sand. Hey, I still have my Mexico charts. They haven't changed or updated them in 20+ years... Oscar Zuniga Medford, OR
KR> 12° ENCUENTRO DE CONSTRUCTORES DE KR, CHIVILCOY 2016
Researched the route from Dallas, Texas to Buenos Aires. Pretty tough flying in a KR but I am game. Total of 31 flight hours one way.?Lots of coastal flying. Once the flights arrive on the South American continent we have to get over to the East of the cordillera (mountain range) at the easiest crossing. Its a nice exercise in navigation. Luis ClaudioDallas, Texas On Monday, November 28, 2016 7:57 AM, "Teate, Stephen via KRnet" wrote: "Personally, in a couple of years after I have retired, I might want to consider it, especially if we can get a group flying down together." Now that is an excellent idea!! Stephen Teate Paradise, Texas The information in this email is confidential and may be legally privileged. If you are not an intended recipient, you should delete this message. Access to this email by anyone else is unauthorized, and any disclosure, copying, distribution or action taken or omitted in reliance on it is prohibited and may be unlawful. ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.orgto change options To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org
KR> Useful Load
Hi I posted this a while back, Can i assume that no one has used the formula to determine stall speed? Not sure how to with the RAF48, no idea what the Coefficiant of Lift is, although the "new" airfoil probably has it someplace, or what to input with the density of air number. Anyone care to take a stab at it with the KR1 or 2? > > https://www.quora.com/How-do-you-calculate-the-stall-speed-of-an-aircraft > > > Now from an engineering Point of View > The stall speed of an aircraft is dependent on four parameters, > > Air Density > Wing Area > Coefficient of Lift > Weight of the Aircraft > > > The exact formula is > V = ?( 2 W g / ? S Clmax ) > > Where, > V = Stall Speed > W = Weight of the aircraft > g = 9.81 (Acc. Due to Gravity) > ? = Density of Air > S = Wing Area > Clmax = Coefficient of Lift at Stall
KR> Useful Load
Kayak Chris wrote: > Can i assume that no one has used the formula to determine stall > speed? Not sure how to with the RAF48, no idea what the Coefficiant of > Lift is, although the "new" airfoil probably has it someplace, or what > to input with the density of air number. Anyone care to take a stab at > it with the KR1 or 2? See the diagram next to the bottom of http://www.n56ml.com/kraf48.html for the max lift coefficient, which is the Eppler code diagram, and was done fairly recently, calculated from the coordinates of the RAF48. I don't claim to be an aerodynamicist, but I would choose use the solid Re (Reynolds number) line (1x106) curve to be conservative (based on 50 mph stall at 15 degrees AOA, standard air density, and 42" average wing chord (anal extraction). This gives a ~Re of 1.7M or so (and the solid plotted line represents 1.0M). I'd work the details and give all my assumptions, but as soon as I do, some real aero engineer will pick it apart to make me look stupid, so I'll let him make the assumptions and provide results, and take the glory. I did this calc 20 years ago, and the units were the PITA, but using an online converter, it makes it easy. If nobody's done it by this weekend, I'll do it again. I haven't volunteered because I've (almost) learned to quit volunteering to do stuff that other people can do...I couldn't get everything done that I plan to do before I die, even if I lived another 50 years! [I'm getting selfish with my time]. The table at the very bottom of the page is for the RAF40, which is something like 1.33 at 16 degree AOA "un-flapped", which is what almost all of the KRs are. And the KRs that have flaps are not full span, for sure. It's provided as it probably came from real wind tunnel data, but was likely generated in the 1930's or 40's, although the thinner chord would likely have a little less lift anyway. Density of air is "standard air density", which you are probably familiar with, standard pressure and temperature. Either find a density that's in the proper units, or put conversion factors in the equation. I'm supposed to be working right now... Mark Langford, Harvest, AL ML "at" N56ML.com www.N56ML.com
KR> Useful Load
Chris, Concur with Mark. I don't think there is going to be any value in doing the calculation. As I recall from my engineering courses on aerodynamics, the equations are just predictors - you must test the airfoil to get the results. It is a circular loop; calc - test - revise your original data to conform to results, do all over again. That is why wing tunnel testing is still required. There are plenty of KRs flying. The stall speeds are pretty close to the published data. Keep it light and it will stall at 50-55 mph. Thanks, Rob Schmitt N1852Z Kansas City, MO -Original Message- From: KRnet [mailto:krnet-bounces at list.krnet.org] On Behalf Of Mark Langford via KRnet Sent: Tuesday, November 29, 2016 6:51 AM To: KRnet Cc: ml at n56ml.com Subject: Re: KR> Useful Load Kayak Chris wrote: > Can i assume that no one has used the formula to determine stall > speed? Not sure how to with the RAF48, no idea what the Coefficiant of > Lift is, although the "new" airfoil probably has it someplace, or what > to input with the density of air number. Anyone care to take a stab at > it with the KR1 or 2? See the diagram next to the bottom of http://www.n56ml.com/kraf48.html for the max lift coefficient, which is the Eppler code diagram, and was done fairly recently, calculated from the coordinates of the RAF48. I don't claim to be an aerodynamicist, but I would choose use the solid Re (Reynolds number) line (1x106) curve to be conservative (based on 50 mph stall at 15 degrees AOA, standard air density, and 42" average wing chord (anal extraction). This gives a ~Re of 1.7M or so (and the solid plotted line represents 1.0M). I'd work the details and give all my assumptions, but as soon as I do, some real aero engineer will pick it apart to make me look stupid, so I'll let him make the assumptions and provide results, and take the glory. I did this calc 20 years ago, and the units were the PITA, but using an online converter, it makes it easy. If nobody's done it by this weekend, I'll do it again. I haven't volunteered because I've (almost) learned to quit volunteering to do stuff that other people can do...I couldn't get everything done that I plan to do before I die, even if I lived another 50 years! [I'm getting selfish with my time]. The table at the very bottom of the page is for the RAF40, which is something like 1.33 at 16 degree AOA "un-flapped", which is what almost all of the KRs are. And the KRs that have flaps are not full span, for sure. It's provided as it probably came from real wind tunnel data, but was likely generated in the 1930's or 40's, although the thinner chord would likely have a little less lift anyway. Density of air is "standard air density", which you are probably familiar with, standard pressure and temperature. Either find a density that's in the proper units, or put conversion factors in the equation. I'm supposed to be working right now... Mark Langford, Harvest, AL ML "at" N56ML.com www.N56ML.com ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org
KR> flying to Mexico and points south
KR> Useful Load
thanks, I agree with mark not to misuse our precious time! my question is related to that I simply may want my bird (KR1) to be light sport compliant. 51mph does it, 55 doesnt. but I plan mine to be simple and light, so I guess it should be fine. > > There are plenty of KRs flying. The stall speeds are pretty close to the > published data. Keep it light and it will stall at 50-55 mph. >
KR> Fwd: for sale
I'm selling this project. I built for experimental exercise but had enough. It was fun and educational but no longer interested in putting more time into correcting wing/aileron design to make it fly right. I had made two wild and crazy flights to determine full width outboard wing flaperons did not work as well as designed and maybe too much elevator. It has completely rebuilt O-200 with 4.6 hours. $32k invested. If interested, take it off line to discuss. See pictures on dropbox link: https://www.dropbox.com/sh/8dh89j0jjeznjtc/AACOjj5PHkpKIg9wKl7DcK46a?dl=0 -- *Gary * /Soli Deo Gloria/
KR> flying to Mexico and points south
I think a better place to fly to then Mexico is the Bahamas. ?All we need to do is to have a gathering in Florida. Then we could fly to Freeport for lunch. ?It's only 90 mile from West Palm Beach. ? I talked to some people at this year's Gathering. There is interest. : ) Paul Visk ?Belleville Il ?618 406 4705 Sent from my Verizon, Samsung Galaxy smartphone -___
