Bong report June 26 2004

[solrules]

Perfect day! For thoes of you who fly there, you know it is a good day when there are a few clouds in the sky and the wind is under 15MPH

There were 4 M class flights, and about 4 cert flights as well.

I'll tell you about my group's endeavours:

I launched my VB Javelin on a G75 (good motor!) -M. Flew perfectly, ejection a bit late. It had a Garmin GPS (not sure the model #, ClusterWiz can get it for you) to hopefully record 3d data. However, it only recorded the max speed in horizontal data, so I got the drift rate of 75MPH.

ClusterWiz launched a Super Big Daddy (29mm version with motor mount to the nose cone!) on a G104-L, but we drilled out the delay a tad because it was too long. Streaked off the pad, wobbled a bit from some unstability at first, but it flew perfectly. Chute at apoggee.

ClusterWiz decided to load up his Super Big Daddy with a spare H210-M from the 7 motor cluster, the Apoclypse. This was not even the biggest motor designed for this rocket, and it was huge! On ignition (more on that later), BAM! It was one of the fastest rockets I had ever seen I lost it at apogee. I heard "No chute!" and it core-sampled pretty badly (not that I could see it). One person saw it hit the ground, he gave us a line to walk on. I plugged it into my GPS, bearing 261 degrees. We started walking, but sure enough, it decided on raining lots the day before and we were pretty much walking in ankle deep swamp water. Fun. We looked for about a half hour, but decided that the ground was so soft, it would have totally gone through, making it impossible to spot.

Still have the spot+bearing on the GPS, so there is a chance of recovering it later (but not if it is in the ground!).

Ignition: here was the problem. We used dipped daveyfire igniters (instead of the first fires) for most motor ignition today. Once on the super big daddy, we heard the igniter pop. After a recycle, we found the daveyfire bulb popped, but it did not light the pyrogen! Another rocketteer used our igniters, and they had the exact same thing happen. Twice. In the same rocket/motor. We hypothize that when they were dipped, the pyrogen was not 'stirred' between each ignitor made. This could have caused an unmixed pyrogen, thus causing a failure.

Questions? Comments? Suggestions? Additions? Post-mordem sympathy (talk to clusterwiz)?

Oh yeah, no pics. I use a 35mm camera, so I have to have it developed. I find it makes much better prints for the money I put into the camera.

 

[daveyfire]

Are you using the 28F fusehead or the 28B? The 28Bs will often just blow off the pyrogen coating because they were designed to light black powder. If it's a 28F, you may have moisture in your pyrogen (used to happen to me a lot because of this... I live near the coast). To prevent this from happening (on 28Fs or 28Bs... I've had great success clustering with 28Bs and this method), dip in a very thin coating of pyrogen over the head, but make it long -- that is, dip the match down 4-5" from the head. You can do this by folding over (not touching) about 2" long, dipping, and quickly unfolding while the pyrogen is still wet. That way, the pyrogen on the tip will light without blowing off, but there is still plenty of pyrogen left to light the motor.

Ground test first!

 

[solrules]

Will have to try that. Thanks for the tip. We are using the longer burning, higher current matches (not sure of the designation).