Cameron Anderson
Well-Known Member
The "up" portion of my two-stage flight this weekend went exceedingly well. 3" airframe, AT K400 DMS booster to AT 38/600 i435 RMS in the sustainer to 8,184 feet. The "down" portion was marred by booster buring in ballistically. On-board sustainer video shows clean desperation in just two frames (bad luck on camera angle) initiated by 1gram of BP. After that, the coupler charge was initiated (evidence of charring in new nomex chute shield and recovered e-match) but the coupler never separated from the airframe which meant the booster chute at apogee (with chute release set for 500') never deployed.
Mating was achieved by extending the sustainer airframe below the motor and using a coupler from the booster to slide into the sustainer airframe. Coupler was secured to booster airframe with 2 2-56 nylon shear pins. Twisting was prevented by three 3" aluminium 1/4" posts on the coupler that slid into holes drilled in the sustainer thrust plate. Fit was repeatedly tested and sustainer and booster separated easily if held vertically and two separate ground tests.
What methods are out there to assure clean seperation and coupler separation? I have a feeling loads under boost tweaked the coupler and locked it in.
Mating was achieved by extending the sustainer airframe below the motor and using a coupler from the booster to slide into the sustainer airframe. Coupler was secured to booster airframe with 2 2-56 nylon shear pins. Twisting was prevented by three 3" aluminium 1/4" posts on the coupler that slid into holes drilled in the sustainer thrust plate. Fit was repeatedly tested and sustainer and booster separated easily if held vertically and two separate ground tests.
What methods are out there to assure clean seperation and coupler separation? I have a feeling loads under boost tweaked the coupler and locked it in.