Holy Lift Offs!

Tinkering around with my nephew, designing a rocket for him, unfortunately Pittsburgh Steelers themed, and tried to see what we could do for altitude on a 29mm RMS.
For the most part he would launch on the 29/40-120 set and upto a G64 which RS claims should get around 4000'; if we play with the mass it says 4600'.
RS puts it at 7732' on an I200 and if we tweak the weight for optimal alt it predicts 8062'.
We changed to a streamer.
Still, good thing he's 11, he can walk after it.

Greg

"Unfortunately"?!! :kill:

that would be a cool rocket 8k feet is alot so yeah id say id have a pair of running/walking shoes on hand just for that one

thats quite high, you may want to watch out for a shred

Is this with just motor ejection?..the launch field would be a mere speck from that height !

Yeah, that's on motor ejection.
We dicided to go with a streamer in hope's of migitating drift; we've walked and searched a couple times now. Twice successfully, once not.
The reality is that we are looking to build this so he and his dad (my brother) can launch it on the AT 29/40-120 set with his friends.
Maybe, maybe , with uncle Greg, we could stick an I in there.
This thing started out almost 5 feet tall with larger fins, but we were not at all impressed with the performance so we played around and it looks like I may have gotten myself in trouble.
I had asked him if this year he wanted me to help him design and build a rocket (I'll buy the parts) instead of a Christmas present.

Greg

Are you sure it could stand up to mach 1.2 (rocksim predicted on an I200)? I think that's just asking for a shred.

Originally posted by cjl
Are you sure it could stand up to mach 1.2 (rocksim predicted on an I200)?

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Not in any way, shape, or form.
That's the fun of it.

Greg

You might want a radio tracker in that one!

The I200 is pretty much as long as that rocket...

I made a few tweaks to your rocket and it gets almost 9k out of the I200 now...even more if you switch the fins to thinner G10.

As for shredding - EARS' 'Mr Altitude Attempt', Ady Waters, did his L2 on an unglassed 2" rocket, made of LOC tubing and with plywood fins. No composites, no massive fillets, and it did around 9 or 10kft on a Pro38 J360 - almost certainly (play with a sim) supersonic and no problem.

The recovery was more of an issue, since it came down 3 miles away!

BTW with my sim I get over 5k on the G64. (Hint...set everything to 'polished' and make sure you polish that rocket!)

True - rockets can stand up to more than you might expect. I've flown a 24mm minimum diameter roughly .5 oz (empty) rocket on an F21. Sims say mach 1.2 and 6800 feet. I was expecting a shred - it had balsa fins and estes tubing - but it came down only about 100 feet away (maybe because the motor kicked out, and the nose cone did not) and it was in perfect condition. I had even named it "sacrifice". It got every bit of that altitude - it screamed off the pad, everyone lost it until it came whistling back and stuck in the ground, 45-50 seconds later. It amazed everyone that it survived.

Originally posted by cjl
True - rockets can stand up to more than you might expect. I've flown a 24mm minimum diameter roughly .5 oz (empty) rocket on an F21. Sims say mach 1.2 and 6800 feet. I was expecting a shred - it had balsa fins and estes tubing - but it came down only about 100 feet away (maybe because the motor kicked out, and the nose cone did not) and it was in perfect condition. I had even named it "sacrifice". It got every bit of that altitude - it screamed off the pad, everyone lost it until it came whistling back and stuck in the ground, 45-50 seconds later. It amazed everyone that it survived.

Click to expand...

lol that woulda be fun to watch ......... and to scream HEEEEEAAAAAAAAADDDDDDDDSSSSSSSSSSSSS. lol only close call like that was with a SS1 that didnt have enough nose weight when it came off the pad on a c6 it went crazy when it left the rod and starts loopy looping at 10 feet in the air we was dodging it as it flew by,lol.