Re: [ERPS] Spaceshot 2001 finally getting off the ground in 2002

e have almost as much time on the 400 lb engines as on the 15 lb teacart engine- those twin 2-1/2 minute firings add up! Incidentally, the EZ-Rocket with both engines going is a high S-1400 system; modest thrust but long duration. The propellant cost are about equal to the labor cost of main

Re: [ERPS] Spaceshot 2001 finally getting off the ground in2002

ine's worth, and we're only operating them at about 80% of design thrust (never bothered to ream out the orifices for higher thrust since it seemed a tad overpowered anyway). Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] BayCon micro-report

s, so the total engine count needs to be at least six. > And of course, things will get exciting the moment you try to make a > turn. Yep. I put a fair amount of work back at RotRock into means for torquing that huge momentum wheel over during the ascent burn. Many are the wa

[ERPS] Re: Attn: Doug - how important is dry air?

Randall Clague wrote: > > Hey Doug, > > There's been some discussion on a sublist about using compressed air for a > pressurant, as long as we're doing monoprop. The issue of humidity came up... > > > > Since the air runs straight through the compressor and doesn't sit > > > in a storage tank,

Re: [ERPS] Attn: Doug - how important is dry air?

Randall Clague wrote: > > At 07:58 PM 06/05/2002, The Silent Observer wrote: > > >Condensation is also a problem with SCUBA tanks; if they're allowed to > >drain off faster than the normal rate of breathing consumption there can > >be enough cooling effect to condense liquid water in the tank an

Re: [ERPS] Attn: Doug - how important is dry air?

Randall Clague wrote: > > At 10:13 PM 06/05/2002, Doug Jones wrote: > > >I dunno if you'd like spitting H2O2 ice out at high speed... > > We would not; the cat pack won't work with peroxide ice worth a darn. How > do we avoid this? Oh, I meant spitting ice o

Re: [ERPS] Attn: Doug - how important is dry air?

pay rental fees for the rest of time. In my spreadsheet, I get about 22 cascade fills of a 1 liter flight bottle from a 45 liter 2500 psi bottle plus a 37 liter 6000 psi bottle before the 6k is under 4500 psi. -- Doug Jones, Rocket Plumber (perforce) ___ ERPS

Re: [ERPS] Attn: Doug - how important is dry air?

ir packs run around there, too? Yes, the 5500 psi bottles we have on the EZ-Rocket started life at firefighters' breathing air bottles. Mako sells 6000 psi 4-stage compressors with fancy filtering attachments, turnkey. I want. http://www.compairmako.com/fire.html -- Doug Jones, Rock

Re: [ERPS] Attn: Doug - how important is dry air?

Ian Woollard wrote: > > Maybe you could put some sort of dessicant in the tank? > Loose desiccant in the tank is guaranteed to cause particulate problems in your regulator, a cure worse than the disease. They way it's usually done is with first, a condenser which captures most of the water and

Re: [ERPS] Cheap tank!

John Carmack wrote: > > I finally got a distributor willing to sell me single units of the > Structural composite tanks: Performance Water 714-736-0137 > > The part I am looking at is pn:31573, a 21"x36" tank with 4" threaded > flanges on top and bottom. It weighs 46 pounds (less, if you remove

Re: [ERPS] A Rocket A Day

vailable, high performance, and is routinely handled safely by thousands of workers around the world every day. HTP is not. -- Doug Jones, Rocket Plumber Scares me and *I'm* fearless. ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] A Rocket A Day

the good work that has been done with it. On the other hand, I feel that designing a new vehicle to use tons of it at a time, several times a day, is not reasonable. -- Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] immersion cooled chamber

John Carmack wrote: > > We are going to try something that I have seen Doug swear up and down > won't work -- water immersion cooling. I have a number of "nudges" > that may add up to enough to make it viable: Hey, I don't *know* that it won't work, just that even with forced cooling I've had c

Re: [ERPS] Armadillo update

, crashing the PLC controller. I punted and put it on an external 5 amp supply, sorry I didn't mention it earlier. Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Rocket Guy on /.

Michael Wallis wrote: > > Hi ... > > Slashdot is featuring answers to 11 questions submitted by readers to > Brian Walker, the Rocket Guy up in Oregon. Interesting answers. > > I particularly noted question ten: "How d

[ERPS] Busy day in Mojave yesterday...

http://www.xcor.com/ezflight13.html -- Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Busy day in Mojave yesterday...

15) Download GPS data Of course, I've oversimplified too; I think the key difference is that we don't take apart or reassemble anything, but our propellant loading is much more complex. I've said it before but it bears repeating- we're doing what we must to prepare for our future vehic

Re: [ERPS] Minutes of ERPS #242

[EMAIL PROTECTED] wrote: > XCOR has received the payment for its high-pressure tank. Two > other disbursements were made to members for parts they had > purchased. I'll be happy to help with loading this bottle up anytime someone can pick it up. Bear in mind that it is 57.5" tall, 9" diamet

Re: [ERPS] CAD programs

Julie Porter wrote: >>As has been pointed out, PS is a printing language and not that good >>for technical drawings. >> >> Michael > > Too right. And this from someone who used it daily for years. > DXF is the best way to archive documents. > > PDF has it's uses. I have not upgraded in a while

Re: [ERPS] over-expansion issues

Bill Clawson wrote: > Hi All, > > Since our chamber pressure on KISS was designed to be about 300 PSI and air > pressure is running at 14.7 PSI, wouldn't the ideal ratio of nozzle area to > throat area be about 20:1? All our engines seem to have less than this > expansion ratio and I was wonderi

Re: [ERPS] On the road

Randall Clague wrote: > I'm off - but then you knew that. > > I'm on the road for the next few days. Among my errands is a trip to > Mojave to say hi to our friends at XCOR, and pick up our high pressure > nitrogen tank. I expect to be there on Thursday, though with only two > static tests and

Re: [ERPS] Cool FETs!

ed coils, but that's just to reduce the opportunities for shorting out the power supply. One problem with low-side drive circuits is that you have low-impedance connections to system voltage running all over the place, energized even when the device is off. One slip with a tool to

Re: [ERPS] Cool FETs!

[EMAIL PROTECTED] wrote: > Doesn't the DC motor have a substantial L that would cause a > substantial delta-V when the FET is turned on or off? > > Dan > > In a message dated 9/23/02 2:58:12 PM, [EMAIL PROTECTED] writes: > > << No, the supply current drops to zero at the same time that the FET

Re: Emergency shut down (Re: [ERPS] Peroxide biprop flies at BALLS)

Henry Spencer wrote: > On Sat, 28 Sep 2002, Randall Clague wrote: > >>>The other thought is - in such a situation, would an orderly shutdown >>>actually be quick enough and less dangerous? >> >>Good point. If we automate the shutdown sequence... > > > Of course, there is the question of what h

Re: Emergency shut down (Re: [ERPS] Peroxide biprop flies at BALLS)

Andrew Case wrote: > If the length of the plumbing between valve and injector is different > for fuel & ox, then simultaneous shutdown of the main valves ought > to lead to a timing difference in the shutdown _at_the_injectors_. > This obviously glosses over issues like differences in plumbing di

Re: [ERPS] Peroxide biprop flies at BALLS

Paul F. Dietz wrote: > Henry Spencer wrote: > > >>Since the plumbing systems for the two propellants necessarily meet in the >>chamber, there is inevitably a path back as far as the lowest oxidizer >>valve(s). The question is whether procedural measures like purges can >>keep that path from eve

Re: [ERPS] FYI: Sci-Fi Convention in Foster City

Aleta Jackson wrote: > BTW, the EZ-Rocket will be on display at the Edwards AFB airshow on 25 > October. We are the _only_ civilian aircraft at the show, which its > planners intend to make up for having to cancel last year's show because > of 9/11. Should be quite interesting... ;-> Aleta Minor

Re: [ERPS] KISS III Propulsion System Test

Randall Clague wrote: On Thu, 31 Oct 2002 23:53:58 -0800, <[EMAIL PROTECTED]> wrote: Tape heaters are inappropriate for Spike, since the propellant tank is part of the aeroshell and it needs to be very clean aerodynamically Hm, I'd been assuming the tanks were not integral. If they are, the

Re: [ERPS] Meeting tonight

Randall Clague wrote: On Thu, 7 Nov 2002 13:57:46 -0600, Rick Eversole <[EMAIL PROTECTED]> wrote: Speaking of weather ... Tehacipi pass has a high wind alert through Friday evening. Sustained winds of 30mph with gusts to 80mph... Oh, it's calmed down, then. Last report I read said sustained

[ERPS] Winds

Randall Clague wrote: On Thu, 07 Nov 2002 16:52:26 -0800, Doug Jones <[EMAIL PROTECTED]> wrote: You lightweights- I went to college in Boulder, and I was living in a basement apartment 1/4 mile from NCAR the night in January 1982 when their anemometer died at 137 mph. Must admit

Re: [ERPS] Winds

Randall Clague wrote: On Thu, 07 Nov 2002 18:14:52 -0800, Doug Jones <[EMAIL PROTECTED]> wrote: We should have known the storm was coming when the tarantulas started moving into the bunker... Hm, the spiders were smart enough to come in out of the storm, and the rocket engineers weren

Re: [ERPS] Armadillo Nov 10

John Carmack wrote: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=181 Two videos included. > Neither one pulled the little chute out of the bottom of the > bag, resulting in a ballistic impact of the tower structure. > The next test will use a thin Kevlar thread, which break

Re: [ERPS] Vibration testing

Randall Clague wrote: The chug frequency wasn't constant; we heard it changing pitch. That could be explained by doppler, since the vehicle approaches mach one in just a few seconds, the chug rate would appear to drop even if it were constant. I think for reduction purposes we can assume the

Re: [ERPS] Vibration testing

Pierce Nichols wrote: > I'm not sure how you are going to get better than the new data > aquisition system. IIRC, it's 20 kHz per channel, and therefore > should record anything you can see on the scope, and most of the > audible range. I've run the Omega DAQ-802 at 40 kS/s on a single channel, a

Re: [ERPS] Homeland Security Act and rocket motors

[EMAIL PROTECTED] wrote: As a list member I would like to welcome any government agents who might be monitoring this discussion, be you robot or real flesh human. I can't tell you how safe it makes me feel that someone is wa Is it just me, or is the list server stuttering? I seem to have r

Re: [ERPS] Slashdotters want to be astronauts

[EMAIL PROTECTED] wrote: That reminds me, how do you make space exciting for girls and women? It is a very white male-dominated field. Space Tourism is one option. But that's just me. :-) All my girlfriends have gotten the idea when I started talking about honeymoon hotels in zero gee... bu

Re: [ERPS] Trajectory, schmajectory

Andrew Case wrote: On Thursday, January 9, 2003, at 12:55 AM, Randall Clague wrote: This of course is hard on the vehicle. I believe it was Andrew Case who called this maneuver "lithobraking." :-) Sadly, I can't claim credit for this bon mot. I picked it up second hand from one of the sp

Re: [ERPS] [ikluft@thunder.sbay.org: [SAT-L] shuttle disaster]

ement in the chain of events. The temetry and voice recordings will, with luck, tell a more complete tale. It's a grim test case, but this is another data point for Ec calculations. Damn. Doug Jones ___ ERPS-list mailing list [EMAIL PROTE

Re: [ERPS] TPS options

ugly, and we slagged several chambers before going back to milled slot regenerative cooling. Better to use well controlled manifolds and orifices. Laminate structures (or platelets as Aerojet calls them) can hide a lot of complexity in an elegantly simple part. --

Re: [ERPS] A question for those who saw Columbia locally (inCalifornia)

s in the record without contamination from later information, and has little value since stills and video have surfaced since then. -- Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] X-15 reusability, parachutes

onvenience store in North Edwards, on Hwy 58 just off base. He said that a USAF major working on X-15 would tell him the evening before about most flights, and the %*&#@$ ventral fin often landed in the power lines and cut the lights in his store. Truth is stranger than fiction...

Re: [ERPS] musings

Our next vehicle will incorporate lesons learned, and the workload should in many ways be lower. We're aiming at one hour turn with a 3 man crew (two with the vehicle, the third fetching tools, moving trucks, etc.) Doug Jones ___ ERPS-list mail

Re: [ERPS] Slashdot article

o that's what was in all those barrels in Doom. Inaccurate, of course, but... -- Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Orbital pix of STS-107

Michael Wallis wrote: Keep in mind that he resolution seen in the photos released from AMOS may not be as detailed as possible. Either way, you're right. It would have been rough. There is the possibility that Atlantis could have been preped and sent to join her in less than 2 week, but it would

Re: [ERPS] Armadillo March 8

John Carmack wrote: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=196 For your cabin air system, may I suggest an absolute back pressure regulator instead of a vent, and a calibrated orifice on a low pressure regulator? This would give a continuous flow independent of externa

Re: [ERPS] Armadillo March 8

John Carmack wrote: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=196 Another thought- any particular reason why you don't want to give the pilot manual handles for drogue & main & reserve deployment, and for main release? As the old skydiving saying goes, "You keep pulling

Re: [ERPS] Primary factors for designing BP engine - where to startfrom

Randall Clague wrote: Thanks! It's quite the culture change. I'm still marveling at not having to lock my car when I get to work. :-) Oh boy, it's time to haze the new guy Doug ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/

Re: [ERPS] Armadillo March 22

John Carmack wrote: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=198 > We put the cabin on the other side of a concrete wall, and > started bringing the pressure up. At 17 PSI... From other context, this sounds suspiciously like a pneumatic test, not a hydro test. This is a

Re: [ERPS] Re: Casualties/Launch

Randall Clague wrote: Now, you can take the aging vehicle out of revenue service, and put it back in flight test; then you can crash it all you want. "Why do you keep crashing that thing?" "We've been trying to wear one out. Hallelujah, we've got data for O&M now." :-) This is where biting the b

Re: [ERPS] Armadillo helicopter drop test

John Carmack wrote: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=215 Lots of pictures and video. John Carmack Man, that brought back memories of skydiving days gone by- especially the Feet-Knees-Forehead style landing ;) Doug ___

Re: [ERPS] Low pressure tanks?

ority of aerodynamic heating anyway. The best reply to such concerns is, "We should have such problems!" Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Low pressure tanks?

no macroscopic work, does work against the van der walls force. A little googling reveals: http://js082.k12.sd.us/van%20der%20Walls%20forces.htm http://science.widener.edu/~svanbram/chem145/ch12/vanderwalls.pdf Man, I have a mind like a packrat. -- Doug Jones

Re: [ERPS] Pressure Suit

ussian.htm, typical Orlan suit dP is less than 4 psi in normal operation. Even at the 5.8 psi max dP, the pressure ratio would be much less than two, so no decompression issues would arise (although no unpressurized high-altitude flight should be undertaken in the next 24 ho

OT Re: [ERPS] This is one way to do it - Wonder it is works?

Randall Clague wrote: On Wed, 10 Sep 2003 10:18:09 -0500, "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> wrote: Cruise missle built from Ebay parts. :) http://www.sptimes.com/2003/09/09/Floridian/Just_over_1_000__and_.shtml Bosh. R/C model airplane built from eBay parts, for $5000, not $1000. Is it

Re: [ERPS] not completely off topic

Andrew Case wrote: On Saturday, September 13, 2003, at 04:14 AM, Randall Clague wrote: On Fri, 12 Sep 2003 18:44:08 -0400 (EDT), Henry Spencer <[EMAIL PROTECTED]> wrote: The "documentation" is mostly part of the problem, not part of the solution. Its presence, in overwhelming profusion, should le

Re: [ERPS] 7 th HP int. conference 2004

Aleta Jackson wrote: David Weinshenker wrote: Hmmm... I note that one of the themes is to be: "comparison of personnel protection equipment, medical surveillance". This sounds like "we've been using hydrazine for all these years and we're still not sure how not to poison ourselves with it..."

Re: [ERPS] Michelle Murray/AWA/FAA is out of the office.

[EMAIL PROTECTED] wrote: I will be out of the office starting 09/14/2003 and will not return until 09/23/2003. I will be out of the office starting 9/15/03 and will not return until 9/22/03. She's ba-ack! ;) Doug ___ ERPS-list mailing list [EMAIL PROT

[ERPS] Interesting price list

/gal at rho =.78, same price as JP-7 av fuel) LH2 2.50(but only 1.46/gal) The price of LOX kinda drives a stake through the heart of airbreathing concepts... -- Doug Jones, Rocket Plumber XCOR Aerospace POB 1163 Mojave CA 93502 (661) 824-4714

Re: [ERPS] Projects

Alex Fraser wrote: Where is the chatter on this list about ERPS projects? Is the ERPS working on any projects? How are things going? I suspect that most of the progress goes on in face to face meetings and work parties, with reports made at the regular meetings. We hecklers only get the side s

Re: [ERPS] MSNBC article on Carmack

Mike Massee wrote: http://famulus.msnbc.com/famuluscom/bizjournal10-11-010204.asp?bizj=DAL It's a good one. Also mentions XCOR at the end. (that's why Google news alerts sent it to me...) And of course, they misidentified Burt with Dick's credentials, and we all know that XCOR is only 4 years

[ERPS] Re: John's idea about mixed AlH3 + H2O2

H4AlLi probably is quite similar to AlH3, here's an account of its handling qualities: Heh. "Festive grey cloud" indeed. More info:

Re: [ERPS] H2O2/Kerosene burn method

them like any other non-hypergolic propellants should work. Your mileage may vary, don't try this at home, warranty void if seal broken... -- Doug Jones, Rocket Engineer XCOR Aerospace POB 1163 Mojave CA 93502 (661) 824-4714 ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

[ERPS] Re: H2O2/Kerosene burn method

[cc'd to erps list] Henrik Schultz wrote: As long as you have a reasonably studly igniter running in the main chamber (for oneshot use an Estes D6-0 motor works quite well), treating them like any other non-hypergolic propellants should work. Your mileage may vary, don't try this at home, warra

Re: [ERPS] Armadillo Nov 15

h only three cell references. It's like the stock CONVERT function, but much more capable. Good stuff. Doug Jones ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Armadillo Nov 15

Alex Fraser wrote: I think a bright light reflected reflected from a projection screen (like for a slide show) will give you enough bright defused light to see the refraction differences from the shock waves in the plume. Anybody got an old slide projector and screen? You might have to do so

Re: [ERPS] Armadillo nov 22, 2003

I finally got around to viewing the drop test video, and noted the roll axis twist the vehice took on at rebound. It appears that the wire rope bundles deflect sideways a bit when they are compressed, and arranged in a circle like that they induce a torque. Perhaps if you turn them 90 degrees

Re: [ERPS] Scaled Composites goes Mach 1.2!

Aleta Jackson wrote: Sander Pool wrote: Very cool. This is how the Thunderbirds went to Mars a long time ago. Well sortof anyway :-) http://spacedaily.com/news/xprize-03d.html > Check out Alan's photos too. http://www.mojavebooks.com/mhv/031217-1.html Aleta P.S. The Voyager Restaurant ran ou

Re: [ERPS] Scientific American article

000 Yeah, I saw it but didn't want to bang our drum. Joan dropped by a week or so ago to give us a copy and have lunch at her favorite diner ;) The next issue of Popular Science should have an article about the goings-on in Mojave, too. -- Doug Jones, Rocket Engineer XCOR Aerospace POB 11

Re: [ERPS] LOX clenliness (was: peroxide compatibility question)

en flowing it at 400 psi through an aluminum orifice, with no drama. Such filings in GOX with a blind tube would have been far more exciting... -- Doug Jones, Rocket Engineer XCOR Aerospace POB 1163 Mojave CA 93502 (661) 824-4714 ___ ERPS-list mailing

Re: [ERPS] Armadillo April 11, 2004

volume? They're available cheap from McMaster-Carr, plain 304 or 316 stainless spheres with no mounting spuds. http://tinyurl.com/2vver This might let you do a partial propellant load without needing god's own GN2 supply. -- Doug Jones, Rocket Engineer XCOR Aerospace POB 1163 Mojav

Re: [ERPS] Engine design breakthrough

[EMAIL PROTECTED] wrote: Breakthrough in long lived rocket engines: http://www.spacedaily.com/news/rocketscience-04j.html Yawn. Tell them to call me when they hit 500 runs. We've *never* had to polish a chamber. Doug, Rocket Plumber ___ ERPS-list mai

Re: [ERPS] Armadillo May 9, 2004

drag substantially, it would just make me feel better :) -- Doug Jones, Rocket Plumber ___ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list

Re: [ERPS] Scaled Composites latest flight

Sander Pool wrote: Pretty damn awesome that's what that was. And the pilot has some brass ones too taking Spaceship One up that high with a faulty control panel. Or maybe he has a little too much of 'the right stuff'? No, just contingency plans, thought out well in advance. I know that in plannin

Re: [ERPS] Armadillo fligh ttest

John Carmack wrote: Mid-week update for a perfect flight test: http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=263 Man, that's lovely to see. I bet you guys need wider faces to hang your grins on. I'd love to see Burt have some minor setback so that your team can make it a hor

Re: [ERPS] Bad day at Armadillo...

John Carmack wrote: We totaled the big vehicle. http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=272 New and improved version in the works... Omega has a whole line of capacitive level sensors, some with the wetted parts being only 316 SS & Teflon- should be fully compatible with

Re: [ERPS] Hybrid Propellant Concept

#x27;t need a better oxidizer. Ignition may be tough, though- perhaps an innermost layer of sodium or lithium foil would work. -- Doug Jones, Rocket Engineer XCOR Aerospace POB 1163 Mojave CA 93502 (661) 824-4714 ___ ERPS-list mailing list [EMAIL PROTECTED] h

Re: [ERPS] 10/21/2004 Meeting Minutes

the motor speeds respond in a reasonable fashion? If it tried to turn hard when held level, or turns _with_ a pitch or roll forced by hand, that could be a sign of crossed commands or sensors. It should feel "live" in your hand, seeking level... -- Doug Jones, Rocket Engineer XCOR Aerospace