It's hard to say goodbye
Posted by aogMonday, 13 November 2006 at 20:17 TrackBack Ping URL

I went out to do some flying on Sunday but it was a bad day for the club. We lost 5 rockets to premature deployment, one of them my Green Rage 4 (a PML 4” AMRAAM). I sent it up an H218R but I must have not assembled the motor correctly as it deployed almost instantly after burnout. It was a tough rocket but putting out a chute at 300MPH was a bit much for it. Two seconds after this picture was taken, most of the bottom half the rocket was debris floating down. I will rebuild, someday (I have a whole lot of kits partially constructed that I need to finish first).

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cjm Saturday, 18 November 2006 at 11:17

what kind of acceleration and top velocity is that thing capable of ? seems like the real fun would be to fit a guidance system to it, and try “jousting” :)

Annoying Old Guy Saturday, 18 November 2006 at 12:20

None now, it’s broken :-)

I would need to find the simulations, but with the right motor, as it was built, it would not quite break Mach 1. Supersonic flight would require some hardening, especially the fins (those are generally the first thing to fail at high velocity). This launch was probably 5-8 g’s, and a big motor could reach 15-20 g’s (because of various factors, small paper tube rockets tend to have higher accelerations).

People look at guidance systems, but those are very expensive and there are some legal issues best avoided. Swiveling the nozzle isn’t feasible so it would require either strong gyros or aelirons on the fins. The amount of effort to make it all work is just too much. As is, it can take 30-60 minutes to prep the rocket for a launch, which is one reason people who fly big rockets also fly small ones.

cjm Tuesday, 21 November 2006 at 18:48

i guess i would settle for little missiles under the wings of an a/c plane, then, that i could fire off at another a/c plane.

Annoying Old Guy Tuesday, 21 November 2006 at 20:56

I haven’t seen that, but I seen pictures of two projects in that vein.

One guy mounted two 2.1” AMRAAMs (this kit) on the wings of his ultra-light, wired up so he could launch them from the pilot’s seat. A massive violation of rocketry safety codes, but cool looking.

Another guy was in to RC airplanes as well, so he built an X-15 setup. He had a big RC airplane (a B-52 I think, not sure) with a 4 foot wing span. He then built an X-15 rocket to the same scale and slung it under the plane just like the real X-15. He had at least a couple of successful launches, where he’d fly the plane to altitude, drop the X-15 and air start it.

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