- Joined
- May 29, 2019
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Last time at the range, I flew a Big daddy on a G-76 with a 29MM mount. It went well, so I built another one, and changed the following from stock:
CA hardened entire tube above Centering rings
3/8 plywood centering rings
Replaced Fins with Plywood
LOC 38MM MMT w/ aeropack retainer
Nose cone modified
The body tube is still stock
Heavy rocketpoxy fillets external, epoxy internal
Nose weight as required
At the last launch, a couple people (OK, I was one) thought it would be cool to see a Big Daddy on an H-550. I have run sims with this motor and it looks like it could break Mach (1.15-1.3) at around 17-18 oz, and go in the neighborhood of 3000 ft, depending on finish and final weight. I have high confidence in the strength of the fin can. The body is stout, but not LOC tube stout. Motor Mount should be fine. I am most concerned about fin flutter due to large fins, and airframe buckling under the 90G+ acceleration.
Has anyone flown one of these on a motor with this much hit, or with this much speed, or close to it? A baby "I" would probably not go as fast, but altitude could be higher, depending on my choices. I will probably run a big G or baby H first to be sure recovery works smoothly with the large motor.
I'll have plenty of help spotting it and will be running a couple of mylar streamers with a small parachute. Recovery descent will be fairly fast. I'm not worried about breaking it, and have blue tube and heavy nose cone for the next try if needed.
CA hardened entire tube above Centering rings
3/8 plywood centering rings
Replaced Fins with Plywood
LOC 38MM MMT w/ aeropack retainer
Nose cone modified
The body tube is still stock
Heavy rocketpoxy fillets external, epoxy internal
Nose weight as required
At the last launch, a couple people (OK, I was one) thought it would be cool to see a Big Daddy on an H-550. I have run sims with this motor and it looks like it could break Mach (1.15-1.3) at around 17-18 oz, and go in the neighborhood of 3000 ft, depending on finish and final weight. I have high confidence in the strength of the fin can. The body is stout, but not LOC tube stout. Motor Mount should be fine. I am most concerned about fin flutter due to large fins, and airframe buckling under the 90G+ acceleration.
Has anyone flown one of these on a motor with this much hit, or with this much speed, or close to it? A baby "I" would probably not go as fast, but altitude could be higher, depending on my choices. I will probably run a big G or baby H first to be sure recovery works smoothly with the large motor.
I'll have plenty of help spotting it and will be running a couple of mylar streamers with a small parachute. Recovery descent will be fairly fast. I'm not worried about breaking it, and have blue tube and heavy nose cone for the next try if needed.