Brian D. Wendt
The Rocket-Mounted Video Camera Project came to an abrupt end as the V-2 model rocket Prima Donna suffered a catastrophic failure (CATO) on its first launch attempt. Although tragic, the CATO was captured on video from multiple angles, and represents a classic case of a rare Estes engine failure.
An examination of the video and debris suggests that the extreme cold (-15°C) caused the propellant grain to separate from the interior wall of the rocket motor case.
When the motor was ignited, the rising pressure in the combustion chamber forced the unburned portion of the propellant violently up and out of the case, destroying the engine mount and tailcone. The propellant grain was then ejected out the top of the airframe, cracking the base of the nosecone, and continued to sail roughly twenty meters into the air. All of this happened in an instant.
For more information on Estes engine design and catastrophic failure, see “How CATOs Happen.”
Author’s Note
This article was originally published on Principia Labs.
Rocket Stability and Performance