This report summarizes findings for seven launch failures where launch vehicle stages experienced uncontrolled, unpowered flight prior to a destruct action or impacted essentially intact. The analysis used telemetry information for three launch failures, videos of three other launch failures, and a failure report provided by a launch vehicle contractor to estimate aerodynamic loading histories prior to surface impact or a destruct action. In two launch failure cases, a fully fueled upper stage separated from the first stage, continued to impact, and exploded. In three cases, the second stage would likely have continued falling to an intact impact were it not for destructive flight termination. The study concluded that for off-nominal ascent, the typically applied aerodynamic loading limits appropriately predict interstage joint separation. However, the subsequent breakup of propellant tanks is not guaranteed, thus the potential to overestimate fragmentation and inert debris created by these conditions. Video evidence, processed telemetry, and trajectory reconstructions show that tank structures of these liquid-fueled vehicles will survive well past those aerodynamic limits. Depending on the launch vehicle and flight termination system, this may require additional consideration within the flight safety analysis procedure, including modeling survival of intact stages that might be released during a failed launch
Stage Survivability After Launch Abort
2022
21 pages
Report
No indication
English