Friday, December 02, 2011

Tree (the rocket, not an actual tree) recovery mechanism complete

I figured out a kluge to add an...er...recovery system to my MDRA Tree (still no real name). I tied a length of rubber band shock cord to one of the motor mounts.  I wanted it sproingy in the event that the 'chute actually deploys. A 12" nylon 'chute will be attached to this cord.  If wrapped tightly, the chute fits nicely under the motor mount, well out of the way of the fire.  To get the 'chute out, I epoxied a cord to an E9-4 and tied the other end to the 'chutes snap swivel.  The trick is to make sure the 'chute is loose enough to get pulled out when the E9-4 ejects but not when the rocket launches.  So, now everyone can feel better that the rocket won't lawn dart.  I'm not sure whether the rocket is more or less safe now!  It can't be worse than a tree on a K can it?  PS - The NAR has ruled that gluing a thrust ring to a case doesn't void its certification, so a string should be OK too. Oh, wait, this is MDRA...