[ERPS] attitude control of rotary rocket engines

Doug Jones wrote: > Yep. I put a fair amount of work back at RotRock into means for > torquing that huge momentum wheel over during the ascent burn. Differential throttling (simulating the cyclic-pitch function of a helicopter rotor) seems like the best bet. There are a lot of ways to do that,

Re: [ERPS] really nice asteroid: 2002 AA29

The Silent Observer wrote: > ... looks to me like a very high likelihood > that it's a discarded booster stage ... There have got to be dozens of those out there from deep-space missions. Is anyone keeping track? I've had a longstanding desire to point a telescope at the Apollo 10 LEM ascent

[ERPS] 25% less delta-V to the moon!

Henry probably knows about this already, but it was news to me: http://www.stk.com/pdf/white_papers/0800_wsb.pdf There is a class of trajectories from LEO to lunar orbit for which the lunar orbit insertion is entirely ballistic (no delta-V required). This reduces the total delta-V for a one-way

Re: [ERPS] Designing Spikes

David Masten wrote: > 2. The throat dimension is going to be real tough to get right on the > scale we are working at. .020 inches is a ~400N thrust difference. The support structure that holds the plug in place will need to be designed for mechanical trimming of the final clearance. Final trim,

[ERPS] Rotary Rocket on NPR

The Sunday morning program on (American) National Public Radio had an interview with Elizabeth Weil, who has just written a book on Rotary Rocket. The book is: They All Laughed at Christopher Columbus: An Incurable Dreamer Builds the First Civilian Spaceship (Bantam; ISBN: 0553108867). The inter

Re: [ERPS] KISS 3 Flight

Randall Clague wrote: > I thought something had gone wrong with the nozzle, because the plume > was turning sideways - but it was the whole vehicle turning sideways. At that point the rocket was getting into the transonic range where compressibility effects start to do funny things to the aerodyn

Re: [ERPS] Analog Devices MEMS gyro

I have a sample, but I haven't had time to play with it yet. It is a rate gyro (measures angular rate rather than directly measuring attitude). To get attitude, you have to integrate rate. Rate noise density (max spec) is quoted as 0.05 degrees/sec/sqrt(Hz). In other words, in a 100 Hz bandwidth

Re: [ERPS] Analog Devices MEMS gyro

Henry Spencer wrote: > ... it's quite routine in big rockets for the *control* gyros and > the *guidance* gyros to be different hardware. The high-bandwidth control > gyros are used to keep the thing flying in the desired direction, and the > low-bandwidth guidance gyros are used to decide just w

Re: [ERPS] Minutes of ERPS #266

At 09:49 AM 9/1/2003 -0700, [EMAIL PROTECTED] wrote: Minutes of ERPS General Meeting #266 21 August 2003 New Business Stewart Cobb gave what amounts to a lecture on GPS technology. Among other interesting facts, he reported that Serantel (sp?) has teamed up with another

[ERPS] fractional freezing

At 09:59 PM 3/1/2004 +0100, John H. Dom wrote: Does anyone have hands-on experience with the formulations in this USP?: 6,419,771 From the introduction, discussing HTP concentration methods: "Fractional crystallization is also a difficult separation technique due to water occlusion in hydrogen pe

[ERPS] Rutan gets first FAA private launch license

"WASHINGTON - The government on Wednesday awarded [Scaled Composites] the first license for a manned suborbital rocket." Cheers! --Stu ___ ERPS-list mailing list

Re: [ERPS] Armadillo May 9, 2004

At 10:18 PM 5/9/2004 -0400, Henry Spencer wrote: On Sun, 9 May 2004, John Carmack wrote: > http://www.armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=257 Hmm... A possible alternative to the "cracked trace" theory is that it's got Surface Acoustic Wave filters in it somewhere; they are son