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Research & Development HPR "junction box" 11/12/2006 The
new HPR "junction box" allows the existing HPR cable to be plugged
in to operate up to five pads with the club launch panel, in the same
manner as the panel operates a 5-pad rack. Usually for use with up to
five HPR pads, it can also be put to use at lower power demo launches
to fire models off of up to five individual pads.
Flight Report Of DeArman's 3 stage Saturn V "Bad Girl Amended 11-17-2004 Last Saturday we took our 3 stage Saturn V, Bad Girl, out to the B'ham field, of NAR 665 for a second flight. A flight report of the first flight can be seen here: http://sears572.com/supersaturnv.htm B.R.B founder Ron Witherspoon accompanied Verna, my son Louis and myself, to the field. At 2:00pm, the weather was good, partly cloudy, 82* and surface winds 5-8 mph. Chad staging 5 to 5 to 1 has been interesting. The only damage from the first flight was to the LEM portion and it was simple to repair. The flight back in April went pretty well, all things considered and we made some minor adjustments from what we learned from that flight. Mainly, we enlarged the vent holes in the main but just a bit and we used a tiny piece of scotch tape on the joints where separation and staging occurs. For the most part, it seems to have done the trick. After quite a bit of prep, we were ready to go and waited for the wind to die down enough to launch. With video ready, we waited a minute or two before I was able to do a quick 5 count. As I reached 0, Verna pushed the button and the 26.7 ounce Bad Girl lifted off. The 1st stage boost was almost perfectly straight. She rose from the pad, not too fast but steadily increasing in speed. At about 175' up, she seemed to encounter some pretty stiff cross winds and even though was still under power, began to angle sharply to the right. A micro second later at 200' up and now approximately 150' down range, right on cue, she staged smoothly and was still climbing slightly, at about a 10* angle. There was a nice puff of smoke as the second stage powered up and while we couldn't tell how many engines lit, there was one heck of a kick. The 2nd stage greatly increased in speed and was really moving down range as the 1st stage tumbled toward the ground and eventually landed about 200' away. One of those danged vaccu-formed fins popped off but it's repairable. I was feeling pretty good at this point, because I knew we had managed to ignite at least some of the 2nd stage engines and she was moving pretty well, climbing ever so slightly, even if it was mostly down range. As the 2nd stage engines burned out and we approached 3rd stage ignition, I held my breath. Bad Girl was now about 300' up and 500 ' down range. I waited for it but there was no 3rd stage ignition. She coasted for a moment before the ejections fired and deployed one of the 2 chutes of the 2nd stage and it floated gently to the ground about 600' down range. The 3rd stage continued on at a good clip. It nosed in about 800' down range, at the back of an asphalt parking lot. The capsule was vaporized and the LEM portion was completely crushed. The rest of bad Girl is in pretty good shape and will make a 3rd flight as soon as we can make the needed repairs. After the second flight, we were excited to find that we managed to ignite 9 out of 11 engines. Not an easy feat, since the tops of the 1st stage engines are 10.5" from the bottom of the 2nd stage engines. As usual, we got all 5 of the 1st stage engines and managed to chad stage all 4 outboards of the 2nd stage. The only one that failed to ignite on the 2nd stage was the core engine, which also resulted in no possibility of the single 3rd stage engine ignition. While this flight fell just short of our ultimate goal, we came closer, learned more and had greater success than the first flight. The first flight we were 6 out of 11. This time we were 9 out of 11. The damage is repairable and we'll try it again. 1st Stage
Since Bad Girl is built from the standard 2157 Estes kit made
from balsa and cardboard, one of the things we had to manage, was what
the point blank exhaust from the 2nd stage engines, would do to the top
of the 1st stage. 2nd Stage
3rd Stage - LEM damage
Additional information on this project....... The latest flight of Bad Girl was very interesting. After a great boost from all 5 first stage engines, she staged and for the first time we managed to get all 5 engines of the second stage to ignite. At first glance, we had originally thought it was only 4 and that we missed the core B6 because the nozzle appeared to be clean after the flight, while all 4 nozzles of the B4-2's were pretty well toasted. After Verna
& I had time to carefully remove and inspect them all, we
found that we had indeed managed to ignite the B6 core engine, as
well as all 4 B4's. I had placed a small amount of finely crushed bp in
the top of the B6 just prior to launch in order to aid in getting more
hot particles to the nozzle of the B6 of the second stage and it seems
to have worked. We will try the method again on the 3rd stage B4-2
engine on the next flight, if I can't find another option.
Close inspection of the engines of the last 2 flights make it glaringly obvious, that the difficulty in igniting the B6-0 engine is that the nozzles are noticeably smaller than the B4 series. The B4's are easily ignited, even chad staging them 10.5" apart, as long as the tubes and main bt are adequately vented. I think I would have a simple solution, if there were just a B4-0 on the market. The rocket sustained
only minor damage to 1 fin of the 1st stage and has been repaired.
Hopefully flight #4 will be a complete success.
Randy Visit the club website of the Birmingham Rocket Boys NAR 665 at: http://www.birminghamrocketboys.com/
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