With no wind and overcast, 80 degree weather I decided to have a rare summer launch. My son's Dragonite broke a few shroud lines and somehow lost a fin, but my daughter's Cosmic Cobra flew perfectly. That was an abrupt end to the good flights. My Helicat and my daughter's Sky Twister both failed to deploy 'chutes and nose dived back to earth. Unfortunately they also decided to fly off to the side so instead of landing in the soft, wet grass of the park they landed in the hard AZ desert soil which is about as soft as concrete.
I assumed that my chute-inside-the-copter-blades technique had caused the NC to stick inside the BT, or that the ridiculous humidity, 66%, had caused them to stick. As I inspected them at home I found that the small, plastic pins the Helicat used as engine blocks had finally failed causing the motor to shoot up inside the first BT. I knew that would happen sooner or later to one of them so that explains one of them. The motor in the Sky Twister was still in place, but the clay cap that serves as a forward closure was still in place, well mostly.
I took the motors out of the other two rockets and a large piece of the clay cap fell out of the Cobra's motor (on bottom) and half of her wadding was still inside the body.
Can this much clay remaining in place prevent the ejection charge enough to cause a lawn dart? This level of humidity is very rare in AZ. Does anyone know if humidity has an effect on motor performance?