Thursday, September 18, 2008


I got up at 6:30 am on Tueasday. I went to work and did a few hours of “Support”. I spent the balance of the day double checking everything on the rocket. We left the house at 8:30 PM headed for  FAR.  While filling the truck with gas  I noticed something on the vehicle was rubbing that should not be rubbing back to the house realign the main valve and leave at 9:15PM arrive on site a 1:00 am. Sun comes up at ~6:30 finish unpacking and setting up the vehicle. First thethered flight attempt at 9:00 am. The first attempt is a no launch as we had made some adjustments to the “Throttle controls “  and we had a sign wrong on the vertical acceleration. Played with software for an hour tried again. Between 10:am and 6:00 PM we did 8 or 9 short less than 10 second flights. We were trying to squeze in one more flight before dark, alas the data reduction from the previous flight pushed us past dark. We packed up in the dark and left the site at 8:30PM We drove to Mojave had dinner and then drove home. Arrived home at 1:15 AM. I slept the first half of the drive and drove the 2nd half. I’m now wide awake (and hence everyone gets an update) Many thanks to Charles Pooley and Kevin Baxter for their help today.

Good news and several problems:

Good news: We had almost no  hardware or electronic issues, we had 8 or 9 flights with ZERO damage. We got data from all but one flight and good video from two or three angles for each flight.


1)The motor is really inconsistant. I think there are issues with the catalyst. We had clogging issues with the aluminum plumbing, we now are all 100% stainless, but the catalyst still has issues, we are going to flush the system and see if anything is clogged. My guess is that one of the checkvalves or orfices is clogged.

2)The Helicopter manuvers differently than the rocket. When you tip the helicopter to the left, the helicopter moves immediatly to the left, when you tip the rocket to the left, the vectored thrust act of tipping actually moves you to the right. The helicopter also has a  LOT more damping than the rocket does. I think we need to add an explict pitch/roll rate loop to the code.

3)The Rocket is really sensitive to the horizontal CG we need to balance better.

4)Minor: A Black plastic pelican case (Holding the telmetry radio) gets WAAAY to hot in the Mojave sun. IT needs to be shaded or it  starts getting flakey. When we found this problem it was TOO hot to touch.



Anonymous said...

White gaffer's tape is your friend.

-Doug Jones

heroineworshipper said...

Enjoy rate damping. The rocket should be more stable than a flybarless copter but not a flybarred copter.