I've flown lots of E15-7's and F50-10's recently that I got when
Rocketvision folded and have had this happen a few times and have developed
a theory.
I think that when the copperhead lights, it can shift downward in the motor
and lights the fuel grain somewhere in the middle, instead of igniting the
fuel grain and the delay grain at the same time. For some reason, the motor
doesn't come up to pressure normally and seems to burn slower. Once the
rocket finally lifts-off, the flight seems normal, but almost always the
delay winds up being waaay too long. I've had several near things, although
have been lucky enough to have ejection just prior to impact and no zippers.
I have 10-12 of these motors left, so I think I'm going to try some other
igniters and see what happens.
--Lance.
Quote:
> Lawn darted my Estes V-2 today. Built the kit close to stock with only
minor
> modifications to the recovery system. Launched it on an Aerotech E15-7.
> Lot's of chuffing before full ignition. Kit made a perfect "scale flight"
> except it landed just shy of England. After it burrowed the nose cone into
> the ground, the recovery system blew the tail assembly off. The only
damage
> was to the body tube so I guess I'm lucky.
> Any insights on how to prevent this chuffing? I've experienced it before
but
> it's never been enough to adversely affect flight. The igniter I used was
a
> Copperhead dipped in Pyrogen and the sealant.
> Vic
by