You know, it would be bloody nice if we could do something about
the multiple-day propagation delay on erps-list. It doesn't do
much good to send a message on Monday about a meeting on Tuesday
when the message doesn't arrive until the wee hours of Friday
morning!
(I'm not positive I would
Of course, as luck would have it, this one propagated within minutes...
was the listserver just down for a few days and nobody noticed?
-dw
David Weinshenker wrote:
You know, it would be bloody nice if we could do something about
the multiple-day propagation delay on erps-list. It doesn't do
Alexander Mikhailov wrote:
Hi,
Dave is working on the freezer to make concentrated
HTP out of lower-grade one, AFAIK. The logic, I
assume, according to
http://www.h2o2.com/intro/properties/pic11a.gif, is
the following: if you have a 30% (or some other lower
grade) HTP, and start cooling
Jonathan Goff wrote:
Hey all,
I'm not actually and ERPS member, but I figured I would bring up the
fact that Dave W. was able to succesfully test his freezer cart this
last weekend at the shop. I can't remember the exact numbers, but he
said he was able to get to something like -65F.
No,
Michael Wallis wrote:
I'd like to focus the after-business discussions on the preliminary
design considerations for KISS IV
- what should we try to accomplish?
- How can we best do that?
- What does that require of the vehicle?
Hmmm... is KISS IV the assumed
[EMAIL PROTECTED] wrote:
Until someone finds money for construction and HTP,
and ongoing expenses, planning beyond this is silly.
From my point of view, the reasons that the peroxide purification
development has been going as slowly as it has are not something
that can be solved by money...
Jerry Durand wrote:
On Tue, October 11, 2005 7:48 pm, Alex Fraser wrote:
I haven't been paying a lot of attention to the world the last couple of
weeks. Seems I heard somewhere that the Chinese have men in space. Is
this true?
Yes, a five day mission.
When did that launch? This is
Pat Kelley wrote:
For those working this project, can you give me an estimate of what it
would take to get you into full-scale production suitable for
experimenters?
Short answer: something like 10-20 months of calendar time, or a way to
clone a second instance of myself that wouldn't be
Michael Wallis wrote:
- Forwarded message from David Weinshenker [EMAIL PROTECTED] -
Date: Thu, 05 May 2005 20:17:59 -0700
From: David Weinshenker [EMAIL PROTECTED]
Subject: Re: [ERPS] E.R.P.S. Annial Meeting - 7 May 2005
Michael -
Any chance of rescheduling for afternoon
[EMAIL PROTECTED] wrote:
For instance, to put the Hubble (v รข?^ 7.575 km/s) in the ISS orbital plane
(inclination change of 23.17 deg), where it would presumably be okay to
service
it by shuttle, you'd need about 3.04 km/s--about enough to send it to Mars!
It's not an impossible number,
George William Herbert wrote:
This morning it's up to Palermo 1.02 (and Torino 4, FWIW!)...
impact probability is shown as 1.6e-02 (1.6%).
This afternoon, up to 2.2% impact risk.
Fortunately the best guess diameter is down a bit to 390 meters
from 440 meters, but that's still 1570
Sean R. Lynch wrote:
Anything with a positive Palermo scale value is interesting.
I could care less about the Torino scale :)
This morning it's up to Palermo 1.02 (and Torino 4, FWIW!)...
impact probability is shown as 1.6e-02 (1.6%).
-dave w
___
From arocket... -dw
Paul Breed wrote:
http://neo.jpl.nasa.gov/risk/
Paul
___
[EMAIL PROTECTED]
http://exrocketry.net/mailman/listinfo/arocket---BeginMessage---
http://neo.jpl.nasa.gov/risk/
Paul
___
Alexander Mikhailov wrote:
Gentlemen,
there is a somewhat theoretical question. It is often
assumed that for bigger (liquid) rockets it's easier
to get the good mass ratio than for smaller one.
Usually one says that the mass of, say, tanks - a
major contributor to the rocket dry weight -
Doug Jones wrote:
Doug Jones, Rocket Engineer
Promotion? :)
-dave w
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[EMAIL PROTECTED]
http://lists.erps.org/mailman/listinfo/erps-list
Jerry Durand wrote:
At 06:05 PM 10/12/2004, Randall Clague wrote:
At 03:33 PM 10/12/2004 -0700, Jerry Durand wrote:
the BATFE Orange Book even specifically defines car airbag actuators as
controlled explosives, requiring that your car be kept in a magazine
Surely individual car owners
John Carmack wrote:
Have you considered just using a dewar of liquid nitrogen for the freeze
wheel? In the long run it would certainly be cheaper to have dedicated
refrigeration, but an easily metered source of unlimited cold would
probably make it easier to prove or disprove the basic idea.
Ian Woollard wrote:
Henry Spencer wrote:
If you're feeling minimal, it can be done with five, as on DC-X's
maneuvering flaps. One deflector on each of four sides to do pitch and
yaw... and then *split* one of them, with the two halves movable
independently, for roll.
No, isn't 3
Hmmm... large dish antennas for radio astronomy or other uses... I'm
wondering if other uses might include space vehicle communications?
(I haven't the faintest idea if this has a save the site plan in it
somewhere, but perhaps it's worth considering...)
-dave w
John F. McGowan, Ph.D. wrote:
Randall Clague wrote:
At 09:39 AM 8/27/2004 -0700, David Weinshenker wrote:
Hmmm... large dish antennas for radio astronomy or other uses... I'm
wondering if other uses might include space vehicle communications?
Five 60 foot dishes is a lot of antenna.
Privately owned Deep Space
Michael Wallis wrote:
Hi ...
The Canadian da Vinci group unvailed their X Prize craft in Toronto
today and announced that they will make their first of 2 X Prize
flights Oct 2nd from their launch site in central Saskatchewan.
http://www.spacedaily.com/2004/040805215635.6hsuznai.html
David Masten wrote:
Well, I wrote the flight control code. I have no idea if it works.
We went to test it, but it didn't initialize the IMU correctly. So I
went back to the imutest code and tried that. Works great from my laptop
and the build server, but not from the PC/104. We checked
So are we having meeting #287 (15 Jul 2004) tonight?
There hasn't been any announcement posted yet - is the
script broken?
-dave w
Michael Wallis wrote:
The next meeting of the Experimental Rocket Propulsion Society will be
held this THURSDAY evening at the Bowers Denny's starting at
[EMAIL PROTECTED] wrote:
John:
In moving to jet vanes, you traded a (relatively) easy engine problem and a
hard control problem for a hard engine problem and a (relatively) easy
control problem.
I'm not John, and he'd be the one to speak definitively, but I'm not sure
that I agree with
Henry Spencer wrote:
Systems with small
numbers of engines require either close matching of engine startup
characteristics, or a pad hold-down system to absorb transient startup
torques.
I suppose that with sufficient throttling capability, it might be possible
to start each engine at
David Masten wrote:
On Fri, 2004-05-21 at 16:06, Julie Porter wrote:
Please in the future try and give at least 24 hours notice. It would also
be nice to tell the secritary Too. 3 of us were there including Chris.
I am not sure why there was any problem. Michael and I had both stated
Jerry Durand wrote:
At 09:49 PM 5/5/2004, Pierce Nichols wrote:
On Wed, 2004-05-05 at 21:44, [EMAIL PROTECTED] wrote:
Good point, against your premise. I'm a boater and I know that an
inflatable boat has a rigid, reinforced fiberglass V hull under it to
take the dynamic stress.
[EMAIL PROTECTED] wrote:
Henry S said:
Any pressurized tank, *especially* one pressurized to the point needed
for
pressure-fed engines, typically makes excellent structure with little or
no added stiffening. (Witness the classical Atlas, whose tanks are just
sheet-metal balloons,
[EMAIL PROTECTED] wrote:
That's all very well. But I have to ask myself: Where are the existing
rockets that use jet vanes for steering? AFAIK, they all use engine
gimballing -- which suggests that vanes have some shortcoming.
(Yes, I know I'm in PCBH territory here. It's a region
Alexander Mikhailov wrote:
Hi,
I'm looking for peroxide compatibility information.
I'd like to have as much of it as possible, but I also
have some specific questions. How compatible is the
copper with the peroxide? What difference for
compatibility the stabilized peroxide makes versus
Henry Spencer wrote:
On Sun, 28 Mar 2004 [EMAIL PROTECTED] wrote:
My understanding is that under GOX or LOX flow within piping, anything
organic will instantly combust...
Not quite. With oxidizers like fluorine or ClF5, that's what will happen.
With oxygen, there may not be any action
Ian Woollard wrote:
That's why payload is important, because it provides income that leads
to profit; and that's why I'm concerned about a 4x reduction in income
per flight. My gut feel is that the profit margin isn't necessarily a
factor of 4 over cost in the first place.
[ .. ]
The other,
Randall Clague wrote:
One wonders, then, about his titular identification of RLVs as
SSTOs. A book published in November 2003 should reflect the current
consensus among hardware developers that SSTO, while technically
interesting, is not on the road to commercial success.
Hmmm SSTO is,
John Carmack wrote:
At 09:08 PM 1/25/2004 -0800, you wrote:
This engine, developed by Rocketdyne for BMD, is the subject of a brief
article in AWST, 12 January 2004, page 44.
Thrust: 1,100 lbf
Length: 8 inches
Chamber P: ~500psi
Fuel: N2O4 MMH
Henry Spencer wrote:
Hazard: it's carcinogenic, and I'm told it's on EPA's P list of
extremely hazardous chemicals (along with hydrazine and assorted
cyanides). Do you really need more?
Nah, that _is_ a bit scary - especially the EPA part!
(_That_ probably means you need a bunch of really
Henry Spencer wrote:
On Sat, 25 Oct 2003, Andrew Case wrote:
Use a pencil, crayon, or felt tip marker. The whole space pen idea is
a triumph of engineering over common sense. This solution also works
for writing upside down. IIRC the early Russian flights used pencils -
don't know what
Pierce Nichols wrote:
On Thu, 2003-10-23 at 00:15, David Masten wrote:
I had figured that to yaw left decrease left engine thrust and increase
right engine thrust simultaneously. Since opposite motors generate
torque in the same direction this should mean no (little) torque change.
Pierce Nichols wrote:
I think it's only a problem for arrangements with small numbers of
engines. If you have more engines, you should be able to be clever about
it. I don't know what the magic number is, but I have hunches. One thing
that came out of my reasoning that is interesting is that
Pierce Nichols wrote:
I think
there would still be a slight lateral force, but not the yaw/pitch
torque that would occur with base-mounted engines.
I don't see how -- please explain.
Well, let's rotate the vehicle 45 degrees, to make the ASCII
art easier - assume we're looking
David Weinshenker wrote:
Pierce Nichols wrote:
On Thu, 2003-10-23 at 00:15, David Masten wrote:
I had figured that to yaw left decrease left engine thrust and increase
right engine thrust simultaneously. Since opposite motors generate
torque in the same direction this should mean
John H. Dom wrote:
it'd be interesting to see what ammount of kerosene or some other chemical
would be needed to make the powder into something liquid like. ..or hmmm
H202 + Al2O3 hybrid anybody?
IIRC a hydride mix or similar was used as a fire starter liquid in Apollo
F1's LOX/kero.
Pierce Nichols wrote:
On Wed, 2003-10-08 at 06:22, Andrew Case wrote:
It's a piece by Edward Tufte on the evils of Powerpoint. It may have
been posted here before, but it's worth reading multiple times, so what
the heck...
That is a summary of a larger essay called 'The Cognitive
Picking up a slightly old thread here:
Randall Clague wrote:
David Anderman once said on the CATS Prize Board that static tests
don't count. HPR doesn't count,
Hmm... the more I think about this remark, the more it bothers me -
and _not_ out of any thought of how it applies to me personally.
Randall Clague wrote:
OK - this matches both my observations and my intuition. But, I don't
see why this is so. Mathematically, it seems to me that a gravity
turn is independent of whether the vehicle is under power; and that ,
second for second, the trajectory will look the same, powered or
Alex Fraser wrote:
Just saying your wiring will work because you
will follow some set rules just ain't real.
Where are we saying that?
You have enough space at the ranch to build a
safe tethered test device.
We may well do something like that for early
Pogo trials: details are still
Pierce Nichols wrote:
I want an eyebolt in
the underside of POGO so that we can cable it to something large and
heavy (like a big slab of concrete) for tether testing.
Is the eyebolt included in the mass budget? :)
-dave w
___
ERPS-list mailing
Andrew Case wrote:
On Tuesday, September 30, 2003, at 09:33 PM, Pierce Nichols wrote:
No. Relatively small perturbations, including relatively slow
pitch changes, could start a little bit of slosh going. If the slosh
frequency is resonant with the lag in the control system, then
Randall Clague wrote:
David Anderman once said on the CATS Prize Board that static tests
don't count. HPR doesn't count, static tests don't count, viewgraphs
don't count, even bench proven hardware doesn't. To really be
somebody in the CATS world, you have to fly something you made
Pierce Nichols wrote:
Dave W has started freezing drug-store peroxide to test his freezer
contraption and expects to move it to the ranch to test with real
peroxide any day now.
Could be this weekend, even.
That might be premature, with you busy and Dave M out of town for the
Rick Eversole wrote:
On Thu, 2003-09-25 at 11:25, [EMAIL PROTECTED] wrote:
http://www.spacedaily.com/news/rocketscience-03zzb.html
Reading the article, it would seem that not many static tests of the
engine design had occurred. I saw no mention of static tests.
There was a press release
Randall Clague wrote:
On Sun, 14 Sep 2003 18:41:31 +0200, John H. Dom
[EMAIL PROTECTED] wrote:
http://www.congrex.nl/03-1/main.html
Cool, a two day workshop on hydrazine. On Sardinia.
Hmmm... I note that one of the themes is to be: comparison
of personnel protection equipment,
Henry Spencer wrote:
On Tue, 9 Sep 2003, Randall Clague wrote:
...They really believe NASA can solve its problems and keep
flying. Reading between the lines, I'm not sure they all believe NASA
-will- solve its problems...but they all believe in NASA as a concept.
It's amazingly
[EMAIL PROTECTED] wrote:
We will meet at Austin's again, but the consensus was that while the food
is still great, the service has deteriorated to unacceptable levels.
Has anyone attempted to raise the service issues with the management?
-dave w
Randall Clague wrote:
Gotten their act together is a bit strong. I think been absolutely
right on the ball is a better description of what would have been
necessary. The main point, that there was initially a chance to save
the crew, is valid.
One thing that NASA probably ought to do is
Randall Clague wrote:
That said, ideology can indeed hinder science, but it can *really*
bollix up engineering. Some years ago, ERPS kept itself ideologically
pure, at the cost of flight testing. It wasn't fun, and I dare say
it's over now.
You're talking about the we don't do
solids /
Tony Fredericks wrote:
Either there is a dearth of messages on the group list, or I've been dropped
from the list.
Looks like you're coming through; there just haven't been a lot of messages lately.
-dave w
___
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[EMAIL
Ian Woollard wrote:
Hey, here's a question. I was reading Sutton the other day and they were
talking about the thermal stresses that Rocket engines face i.e.
positive few hundred C on inside, versus -193 if you regen cool, and
apparently the throat often shrinks by 0.25% or so and cracks up
Ian Woollard wrote:
Randall Clague wrote:
I'm missing something. Why would the glue melt. Especially in a LOX
tank?
Hey, that's a point. How hot does the HTP vapour get in the ullage space
of ERPS's rockets? 60C rise == detonable?
It should be pretty near the original
Michael Wallis wrote:
The next meeting of the Experimental Rocket Propulsion Society will be
held this THURSDAY evening at the South Sunnyvale Coco's starting at 8:00pm.
This Coco's is located on Mary Ave, just south of Fremont near 85 and
I-280. Take the Fremont Ave exit off 85 and go
Pierce Nichols wrote:
I mentioned this to those at CDI on Sat. It's a steam-powered pump with no
moving parts whatsoever, being developed by a British company called
Pursuit Dynamics. They're thinking of using it for boat propulsion and
industrial pumping. I think it might be usable for
[EMAIL PROTECTED] wrote:
We have a reservation for Thursday night, 7-10PM, at the Baker's Square
restaurant in Redwood City.
So the meeting is at 7PM instead of the usual 8PM, or were you giving an hour
margin on the starting time??
-dave w
The latest on legislative actions...
- dave w---BeginMessage---
[ from http://www.californiaspaceauthority.org/pr030605b.html ]
Rep. Ken Calvert Introduces Space Legislation,
Agrees to Assist Hobby Rocketeers
June 5, 2003
Rep. Ken Calvert (Republican, California) introduced the Invest in Space
From another list: update on the legislative campaign. -dw
Ismaeel Abdur-Rasheed wrote:
from John Wickman:
It is time to work your magic again with letters and phone
calls directed to the ATFE and the House of Representatives.
In the last few months, your letters and phone calls have
Randall Clague wrote:
On Sun, 25 May 2003 14:49:49 -0500, John Carmack [EMAIL PROTECTED]
wrote:
Actually, I think most on this list are VTVL advocates, although Randall
may have been corrupted by XCOR by now. :-)
A fair assessment. :-)
Given XCOR's environment and mission, HTHL is
Do we have a meeting scheduled tomorrow? I haven't seen
an annoouncement, but it's the week for it isn't it?
-dave w
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[EMAIL PROTECTED] wrote:
Minutes of ERPS General Meeting #256
20 March 2003
SMARTFLIGHT
---
Dave Weinshenker
Late update:
Fresno launch March 16 was canceled; a make-up
date has been scheduled for April 20. (Possible
test of variant PC-Bird configuration using dual
event
Bill Clawson wrote:
Interesting stuff, but this looks like a research
house. I wonder how hard it is to get a can of the
stuff?
This may be the same stuff that Dan got a sample of...
-dave w
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[EMAIL PROTECTED]
Reopsted from AROCKET: John Wickman is asking for follow-up phone calls
in support for Senator Enzi's proposal to exempt rocket propellants from
the Federal explosives requirements...
-dave w
- - --- -- - -- --- - -
We continue to make progress in the Senate and pick up support. Many of you
Michael Wallis wrote:
SMARTFLIGHT
---
Dave Weinshenker
Dave W flew a 3 HPR rocket bought at Black Rock in 2001. The
Canadian-made Pro-38 motor pushed the rocket to 780 feet --
respectable performance for a G-size motor.
In 2001? And we're only just hearing of this?
Randall Clague wrote:
To the best of my knowledge, we don't have an all up mentality, and never
have had. We may have incrementally tested to higher levels than strict
prudence would have dictated - that third flight in November was pushing it
- but we have always incrementally tested.
Here's the latest on the Wickman legislative campaign.
Paul R. Yarnold, Ph.D. wrote:
ARSA membership and others:
We are waiting for a green light from the staff in Washington to synchronize
with information to be given to each Senator this morning so that your phone
calls and faxes start
The word is go.
Today's the day.
http://www.space-rockets.com/congress.html
-dave w
--
To All ARSA members and Fellow Rocketeers,
GO!!! FAX and Phone Your Senators Now
This morning Senator Enzi sent to all Senators a Dear Colleague letter
John Carmack wrote:
At 01:49 PM 2/28/2003 -0800, you wrote:
Yup , another thing to think about is if you have a lot of nozzles in your
100 ratio plug , after 50,000 ft you shut off 1/2 of them , Instant 200
ratio ! ( Isp 300 to 340 )
I don't think you get to 340 with even an infinite
David Weinshenker wrote:
John Carmack wrote:
At 01:49 PM 2/28/2003 -0800, you wrote:
Yup , another thing to think about is if you have a lot of nozzles in your
100 ratio plug , after 50,000 ft you shut off 1/2 of them , Instant 200
ratio ! ( Isp 300 to 340 )
I don't think you
Randall Clague wrote:
On Mon, 24 Feb 2003 12:59:23 -0500 (EST), Henry Spencer
[EMAIL PROTECTED] wrote:
The attraction is an Isp of 3000-5000s with respectable thrust, enough
to accelerate a realistic vehicle at maybe 0.1G.
Is that a typo? 3000 to 5000 seconds? That's 30,000 to 50,000
Randall Clague wrote:
David Masten wrote:
Weather and seasons are a little different for those of us that
go to the high desert for flying. Summer is not a good time to fly
(but it's a dry heat 105 is damn hot, I don't care if the
humidity is only 4%!).
105 F isn't hot for Mojave. 125
Henry Spencer wrote:
On Mon, 24 Feb 2003, David Weinshenker wrote:
gas core nuclear
Is there such a thing? I hear occasional
references to such a concept, but never
enough detail to get an actual image of
how it would work.
Well, depends on your definition of is. :-) It's been
[EMAIL PROTECTED] wrote:
gas core nuclear
Is there such a thing? I hear occasional
references to such a concept, but never
enough detail to get an actual image of
how it would work.
-dave w
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[EMAIL PROTECTED]
Adrian Tymes wrote:
--- Henry Spencer [EMAIL PROTECTED] wrote:
The big trick
is maintaining a
reasonably stable blob of very hot uranium-rich gas
without having it mix
with the hydrogen too much (because you don't want
to lose fission fuel
out the exhaust) or melt through the
Adrian Tymes wrote:
Show me a fission reactor that could possibly get
political approval for operation during launch today,
especially if the operator is not a governmental
entity.
During launch? I thought any feasible nuclear thruster
was going to be strictly an upper stage engine rather
Randall Clague wrote:
We also have to pick our battles. It is clearly in ERPS' interest to
support John Wickman's proposed legislation removing all rockets from
ATFE jurisdiction. It is less clear that spending our time and energy
on a hip shoot Senate faxathon about solids is a good use of
Henry Spencer wrote:
Heat-exchanger rockets don't have great Isp, but with LH2 they can have
reasonable Isp -- enough better than chemical that SSTO does not look too
difficult -- and they come standard :-) with high efficiency and near-total
insensitivity to laser details. And LLNL had
Michael Wallis wrote:
Henry Spencer wrote:
NASA looked at this for SEI, and concluded that supplying one lunar
mission a year with LOX/LH2 required a 400kW electrolysis plant running
continuously in LEO.
They decided what? Are THEY daft? How big a settlement are they
looking to
[EMAIL PROTECTED] wrote:
There will likely be a somewhat soft physical limit in how rapidly one can
push fuel and oxidizer into the vehicle, but by the standards of an
operational air base, or a Daytona 500 pit crew, 4 hours turnaround would
seem generous, and both involve vehicles arguably
, by the way, so I can
help record the flight.
Sam Coniglio
Home: 415-585-8556
Cell: 408-930-0102
On Thursday, February 13, 2003, at 06:53 PM, David Weinshenker wrote:
[EMAIL PROTECTED] wrote:
SMARTFLIGHT
---
Dave Weinshenker
Launches are set for 15 February
Michael Wallis wrote:
Henry Spencer wrote:
Especially for a big manned spacecraft -- notoriously high on volume and
thus heat-generating equipment and people, and low on surface area -- I
think you're going to be driven to choose the outer layer purely on
thermal issues. Using it for
Randall Clague wrote:
On Mon, 10 Feb 2003 12:38:13 -0800, Pierce Nichols
[EMAIL PROTECTED] wrote:
Achieving such a
turnaround time would also eliminate ablative TPS systems from contention
I don't see this. A vehicle with a field-swappable TPS can have a
fast turnaround. Unlock the
[EMAIL PROTECTED] wrote:
SMARTFLIGHT
---
Dave Weinshenker
Launches are set for 15 February in Livermore and 3rd Sunday im
March at Fresno.
Update - Tripoli Central California (Fresno) launch - actual date scheduled
is Mar. 16 '03
Livermore status is uncertain because of
Adrian Tymes wrote:
http://science.slashdot.org/article.pl?sid=03/02/05/2243243mode=threadtid=134tid=126tid=160
We got slashdotted and we didn't even feel a thing. (At least, so I
conclude from the lack of mention of it.)
*follows link*
*scratches head*
Hmmm... compared to some of the
Alex Fraser wrote:
Lots of good info about the shuttle burn up. With all the talk of NASA I
couldn't help musing about ERPS.
Folks on the list are not actually there at NASA and must rely on
what they read in the press and elsewhere. A similar situation exist for
me in that I am not
Henry Spencer wrote:
On Sat, 8 Feb 2003, Randall Clague wrote:
There are things Hubble has been doing for a
decade that those ground-based telescopes will *never* do.
I was trying to imagine what some of those things might be... Hubble
Deep Field. No ground based telescope -
Henry Spencer wrote:
Well, yes, meeting -- and getting JSC to agree that we meet -- the
visiting vehicle specs might perhaps be a little difficult. (No space
vehicle ever built meets them -- the existing and near-future vehicles
which do visit the station are grandfathered in.)
What do the
[EMAIL PROTECTED] wrote:
On 8 Feb 2003, at 12:15, Randall Clague wrote (in part):
That was Deke's thinking. Launch and reentry were fairly safe because
they were short (though there was that problem on Apollo 18 reentry:
RCS fuel vapor does NOT belong in the crew cabin). He had less
Pierce Nichols wrote:
Another thing that comes out of my reading of the SERV document is
how much the heating will vary across the base heatshield and across the
re-entry profile. At peak heating, the coolest part of the base heat shield
has a heat transfer rate of 244 kJ/sec-m^2.
Henry Spencer wrote:
It also doubles as insulation. The downside is that you get to worry a
fair bit about its mechanical properties; the incredibly tedious process
of filling honeycomb with little squirts of ablator
Did all of the US capsule spacecraft use that particular heat shield
Robert Walsh wrote:
Steve Traugott just called to say he and former ERPS member Ian Kluft
are on the front page of today's SF Chronicle - talking about seeing
Columbia pass overhead Saturday am on it way to history. It also talks
about DC-X and other means of getting people to and from
The observation has been made (I don't know how accurate it is) that
satellite capture and repair, and especially earth return and relaunch,
is really too expensive to be worthwhile in the first place...
Hubble/Solar Max (etc.)could have been replaced for less than
the cost of the repair
Randall Clague wrote:
I have never liked ablative methods. Yet they seem to be the best.
I have a simple philosophy: Do What Works. Ablatives work.
A fundamental issue here seems to be that the Shuttle TPS tile system
has been just barely adequate at best... no previous shuttle actually
From: [EMAIL PROTECTED] (Ian Kluft)
I was hoping to come back from the mountain with a happy story of having seen
a normal space shuttle re-entry. We did see the shuttle come over the Bay
Area. But everyone whom I watched with noticed that the ion trail was much
more obvious than on
Hmm... I presume those specific impulses should be km/sec rather than
m/sec? They seemed on the high side until I noted the expansion conditions
they were determined at: 1000 - 0.2 psia, or 5000:1 pressure ratio...!
(So that's how to get 1.88 km/sec out of
H2O2 monoprop and 3.73 km/sec out of
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