Bunnell Blast Night Launch
NEFAR 10/8/05

Airel airframe, painted yellow.  As if that mattered.  B.
Dr. Rocket 38-720 casing with single moonburner grain containing 3% fine titanium flake.

Time exposure taken with Sony Mavica CD-1000
Night Flight with Ti - delay grain failure

Click Here for high-res version of this photo (1200x1600, 900k)

Click Here to see how this happened (1.8 meg .wmv file, 9 seconds)

What gives?  Examination of the case contents the next day showed that the delay grain had leaked big time.  The O-rings were all eaten away on one side, and the CPVC tube the delay was in was throughly blackened on the other side.

From the appearance of the movie, the parachute must have ejected immediately upon launch, and the rocket is dancing with the open parachute.  
Note the thin trail of smoke to the left of the lower spark-arc, and continuing to the right of the upper arc.  I suspect this is the front end of the airframe, now open, and ejecting some of the motor gasses.  The forward end of the airframe was hot upon retrieval, and contained some burned-propellant-like residue.  

How did it happen?  I am guessing that the delay grain was not seated perfectly, allowing an O-ring to slip into the head end recess and create a gap.  

Jimmy Yawn
Recrystallized Rocketry