Canted 3 engine 1/4A scratch build

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CoachSteve

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This one was my first take at canted engines.
I went with 13mm engines to keep the budget down (and I had a pack of BT-5 laying around :) )
Nose and tail cone are hand rolled paper hardened with CA.
The 3 BT-5 engine tubes converge at the center of mass into a single BT-5 for ejection.
Transitions are traditional Estes paper shrouds.
Rocket stand was just bracket stuff I had lying around
It has flown successfully once (all engines go) and 2 out of 3 engines fired on launch 2 (not so good)
super fun project.


 
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The beauty of the canted engine arrangement is that it opens up options on the aft treatment. Nice job!

Yes, like hauling up skeletons or telescoping body tubes. Make the whole rest of the rocket an "aft treatment." Put a drag tail behind it and fly a WWI or WWII airplane rocket. Put on a kite tail and fly a tapeworm or long streamer tentacles and fly a squid. Put the canted motors up front on the steam locomotive and fly a flexible crazy train rocket. Just get all the motors to light at the same time and they will fly fine! Nice smoke trails going up. Flame fin action helps to stabilize. Motors placed up the rocket good fer stability. They may be funny looking, not as efficient and get the aft treatment from some RSO's, but canted motors rule!
 
I like the center section. So the three 13 mm eject into the single BT 5 tube. Did you have to reinforce it to take 3 charges? Maybe flying with only one or two motors ejecting? I read that the best place for the canted convergence is halfway between the CP and CG, but my TRES still crashes when only two light. Maybe that only works with two slightly canted motors on a very traditional set up. With tree motors the asymmetrical thrust will arch it over unless there are some major corrective issues present.
 
I like the center section. So the three 13 mm eject into the single BT 5 tube. Did you have to reinforce it to take 3 charges? Maybe flying with only one or two motors ejecting? I read that the best place for the canted convergence is halfway between the CP and CG, but my TRES still crashes when only two light. Maybe that only works with two slightly canted motors on a very traditional set up. With tree motors the asymmetrical thrust will arch it over unless there are some major corrective issues present.

I think the proper canting helps some but the misfired canted rocket is still more sensitive to other conditions (like wind). My Deuce has worked on one motor but has also pranged.
 
I like the center section. So the three 13 mm eject into the single BT-5 tube. Did you have to reinforce it to take 3 charges? Maybe flying with only one or two motors ejecting? I read that the best place for the canted convergence is halfway between the CP and CG, but my TRES still crashes when only two light. Maybe that only works with two slightly canted motors on a very traditional set up. With tree motors the asymmetrical thrust will arch it over unless there are some major corrective issues present.

Yeah - all 3 ejection charges hit that single BT-5 - there is quite a long transition of the 3 though - almost the full length of the bottom tube as all as most all the the shroud.

and yeah - the last launch when only 2 motors went was a low altitude sky write :). The maiden launch with all 3 was nice and straight though.
 
Yeah - all 3 ejection charges hut that single BT-5 - there is quite a long transition of the 3 though - almost the full length of the bottom tube as all as most all the the shroud.

and yeah - the last launch when only 2 motors went was a low altitude sky write :). Yhe maiden launch with all 3 was nice and straight though.

Just keep flying and fixing. Have not had a burn through or blistering a little CA couldn't fix.
 
The nose cone is 9" long, there is an 1/8" dowel running up the center that extends through the tip all the way trough the plugged tube coupler I used as the shoulder. The cone is a plain old 81/2 x 11 sheet of copier paper :)
These right here were the real trick though :
 
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