Just glancing through this thread. my Mongoose flew once just a few years ago on A8-0 to A. I recall that the top of the booster got toasted, though I do not remember the rest of the flight profile--whether it angled off oddly or not. I found this completely surprising because I had flown an Estes Scorpion 2-stage for several years and never had this problem (it was one of my old faithful favorites from the mid-late '80s through about 2003-ish when I lost the upper stage--and it's on my want-to-clone-someday list). Even so, I can see a couple of things that may affect things.
- The fact that the booster does not use a stage coupler means that it just drops off after the clear tape burn-through. This *might* present an opportunity for asymmetrical tape burn-through to rotate the un-couplered booster to the side and get some sort of thrust vectoring of the upper stage and even impingement of the exhaust on the tube (in my case). For normal coupled boosters, the tap burn-through happens, then the coupler ensures straight separation.
- Unlike the Scorpion, the Mongoose has a reinforcing ring at the top of the booster. It might be possible that this causes some sort of turbulent flow behavior (like Krushnic effect / Bernoulli lock) that prevents clean separation of booster. No idea if this is possible, and I think it's probably not a factor here. I may have just been very lucky with my Scorpion or unlucky with the one flight of the Mongoose.
The above may have nothing to do with anything (I'm just spitballing here), but I figured it might be worth a mention.
Josh T.