Longest 29mm casing that will fit in a standard AT motor tube

Ive got an Astrobee D that Id like to stuff an H in. Whats the longest case that will fit in the mt with the baffle glued on the top?

ascastil said:

Ive got an Astrobee D that Id like to stuff an H in. Whats the longest case that will fit in the mt with the baffle glued on the top?

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I believe the Astrobee-D has a 117mm motor hook in it. If you used the hook with the appropriate gaps, I believe that the 124mm long 29mm motors will work. If you just used the motor tube and no hook (or baffle or brillo-pad mesh, etc) The motor tube is something like 250mm or so...

I don't believe there are any H realoads for the 124mm length (I could be wrong here). The 29/180 reload which covers most of the level 1 "H" motors is a bit longer at 7.66" (194mm). The hobbyline 29-40/120 would fit, and the G138T would be the biggest motor (still needs an L1 to buy) that you could launch.

If you just used the baffle and got rid of the metal sponge, then you could likely fit the 29-180 reload case and perhaps the 29-240 with an appropriate retainer. The added weight may need some nose cone weight to rebalance.

https://www.aerotech-rocketry.com/customersite/resource_library/instructions/Kit_Instructions/astrobee_d_in_8-04.pdf

The instruction say the hook is 6 and 3/16 inches long, so you would be able to fit only a 29mm 120 case in there, which has no H motors. A 29mm 180 case would extend past the engine hook by about a third of an inch (its 6.8 inches long). Assuming you account for stability using additional nose weight and assuming that the kit can handle it, you could wrap masking tape around the motor and the engine hook to secure it.

No hook, Aeropac retainer. Ive got a 29/180 case, wondering if anything bigger would fit in case I get bored lol.

ScrapDaddy said:

https://www.aerotech-rocketry.com/customersite/resource_library/instructions/Kit_Instructions/astrobee_d_in_8-04.pdf

The instruction say the hook is 6 and 3/16 inches long, so you would be able to fit only a 29mm 120 case in there, which has no H motors. A 29mm 180 case would extend past the engine hook by about a third of an inch (its 6.8 inches long). Assuming you account for stability using additional nose weight and assuming that the kit can handle it, you could wrap masking tape around the motor and the engine hook to secure it.

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The Aerotech rocket that is designed to take an H motor is the Sumo.

When I built mine, left out the motor hook & stop. Used the coupler for av-bay/dual deploy.

I can get a 240 case in there, flies great.

blackjack2564 said:

When I built mine, left out the motor hook & stop. Used the coupler for av-bay/dual deploy.

I can get a 240 case in there, flies great.

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Perfect, exactly what I wanted to hear.

If it's got plastic fins, watch out for flutter. Had an issue with an AT HV Arcas on higher inpulse H's. In retrospect I should'a perhaps laminated the fins with .75 oz cloth with a 45 degree weave angle. One fin root sustained a partial root crack on the
aft end on an H-165. The end of the rocket wobbled just a bit on boost and had a feather soft dual deploy recovery (I modified for DD). I'm sticking with H128's from now on. Nice 1400' apogees and one can watch the process of dual deploy which
as you all know impresses lay people who are unfamiliar with the hobby. Kurt

H-165 Red is my favorite motor for the modified Astrobee-D. Like Kurt mentioned I get 11-1200 ft flights that are entirely seen start to finish. Nice crowd pleaser. I would not use any Warp-9's or other super high thrust motors with plastic fins.......good advice from Kurt.

This would be a nice way to L-1, even on motor deploy, not a long walk.

I built this rocket 2003...14 years ago. Over time fin tips broke, so I just cut them down & kept on flying it!
Lugs on one side & rail buttons on another to fly off either rods or rail.