First scratch built two stage, Stage Fright

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I forgot to post the photos and video.

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It was an okay boost, but after sustainer ignition and separation, the sustainer kind of turned horizontal. I'm thinking it was a little under powered, and didn't have enough momentum for the sustainer's D12-7. Plus, the booster hit the ground hard enough to wrinkle the body tube. Apparently it didn't tumble, but fell straight down and hit on the bottom.

I've decided to build a new booster, this time with a 3x24mm cluster. And in a total departure for Captain Low-N-Slow, I'm going to build it as light as possible. Fiber centering rings instead of plywood, and balsa fins. I'm hoping that the lighter weight and extra thrust will give it a better ride.

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The sustainer was undamaged, but the booster apparently didn't tumble (I didn't see it fall). It looks like it hit butt first very hard, the body tube is crumpled in several places. And it did something to the coupler, it's now very tight.

I've run into this with my 2 stage Magnum Loader. My booster does this as well, but the motor sticks out 12mm so it takes the brunt of the landings. I thought it would tumble also, but it comes down in a nice arc and it "lawndarts" too! I believe that when the booster ejects, it's now tail heavy due to the clay nozzle of the engine, and the fins help give the fore end enough drag so it comes down tail down. I think you're running into the same issue.

Same thing with the motors being tighter than hell, but I think that's due to the inner tube being heated up after ejection and it shrinks. I'll bet if you leave the booster alone for a while the motors will go in and out as normal as the inner tube soaks up some moisture from the atmosphere (theory here).
 
I've run into this with my 2 stage Magnum Loader. My booster does this as well, but the motor sticks out 12mm so it takes the brunt of the landings. I thought it would tumble also, but it comes down in a nice arc and it "lawndarts" too! I believe that when the booster ejects, it's now tail heavy due to the clay nozzle of the engine, and the fins help give the fore end enough drag so it comes down tail down. I think you're running into the same issue.

Same thing with the motors being tighter than hell, but I think that's due to the inner tube being heated up after ejection and it shrinks. I'll bet if you leave the booster alone for a while the motors will go in and out as normal as the inner tube soaks up some moisture from the atmosphere (theory here).

The motors came right out, which surprised me. I'm going to a club launch today, I might fly it as a single stage, or I might just try again as a two stage. The winds are supposed to be very light today, so it would be a perfect time to try again.
 
Sorry to see that happen,great looking rocket.Hope you have better luck on your next launch.cjp.
 
What I would do is..........

With the 2 outer engines, don't vent the gases, but put a short delay engine in there, and rig it to eject a chute.
 
As for the rocket itself going horizontal after separation and 2nd stage ignition, I think you may be on the right track and the engine might not be strong enough to keep the speed increasing or maintaining it.

Either that or the winds were much stronger at the altitude and it wind-cocked like a MOFO.
 
It was an okay boost, but after sustainer ignition and separation, the sustainer kind of turned horizontal. I'm thinking it was a little under powered, and didn't have enough momentum for the sustainer's D12-7. .

One thought is that the single vent hole may have shanked it a bit. But I doubt this, as it seems the sustainer initially continued true until a few moments AFTER staging, rather than deviating at the moment of staging.
 
Don't forget you can simulate just the booster to make sure its unstable by itself.

When the knot came undone on my TLP Hawk, the body tube flutter down rolling axially because without the nose cone, and the weight inside it, the entire body was unstable. No damage.
 
I ordered the parts today to make a new booster. It'll have 3/16" balsa fins and fiber centering rings, to hopefully keep it lighter. It will also have three 24mm motor tubes, for D12-0's. I thought about using longer tubes so I could put E9-0's in it, but decided not to for two reasons. One being weight - the extra weight (albeit slight) of the longer motor tubes, longer motor hooks, and the spacers (when I use D12's). The other and more important reason is that D12's have more initial thrust than E9's.

The three motors will be in a circular pattern instead of three abreast. I'm thinking with the gap, they'll ignite the sustainer motor kind of like a flash pan, even though there won't be a booster motor directly underneath the sustainer motor. I thought about making some sort of "funnel" to guide the hot particles into the sustainer motor, but I don't think it'll be necessary. Famous last words. LOL
 
I ordered the parts today to make a new booster. It'll have 3/16" balsa fins and fiber centering rings, to hopefully keep it lighter. It will also have three 24mm motor tubes, for D12-0's. I thought about using longer tubes so I could put E9-0's in it, but decided not to for two reasons. One being weight - the extra weight (albeit slight) of the longer motor tubes, longer motor hooks, and the spacers (when I use D12's). The other and more important reason is that D12's have more initial thrust than E9's.

The three motors will be in a circular pattern instead of three abreast. I'm thinking with the gap, they'll ignite the sustainer motor kind of like a flash pan, even though there won't be a booster motor directly underneath the sustainer motor. I thought about making some sort of "funnel" to guide the hot particles into the sustainer motor, but I don't think it'll be necessary. Famous last words. LOL

What you could do is have an engine rigged to deploy a small chute or streamer.

This is my next project....But 2 18mm and one 24mm in the booster.
 
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