Flight Log - Ocotillo Club LaunchWoke up at 5:00 a.m. so that I could be at the launch site early. The sun rose as I made my way over the Tecate Divide and down into the badlands. By the time I got there (about 7:00 a.m.), it was already starting to warm up. During the day, the temperatures exceeded 110' with moderate winds. It was nice enough for a while in the morning, but it got really hot by noon. I was processing water about as fast I could drink it. The heat made the walks to get the rockets difficult. I can see how someone could perish in a few hours out here. At 1:00 p.m., I decided it wasn't worth the effort anymore and cut out. The drive was hot and hard as well, with winds and "no air conditioning for the next twenty miles". Still, I was on the range for a good 5 hours, and got four flights in. Some better than others :-|
Flight #1 -
GPARS #3 (I211-M) One of my goals for today was to try to get GPARS flying right, so for the first flight of the day I chose to send her up on an I211M. The boost was nice and straight with the rocket climbing nearly out of sight. It opened up and separated correctly, but the parafoil parachute did not open all the way. It remained folded as the electronics module made it's way to the ground. The parafoil came down a little quicker than the booster, but there was no damage to the innards. Obviously, I never had R/C control of the chute. 
The booster landed about 1/2 mile away, the parafoil a little less. Even at 8:00 a.m. it was pretty hot. I started thinking about a shortened day.
Flight #2 -
DoubleTrouble #3 (J90-L shaved) Click here or on the photo below to see a 3M mpg movie of this flight. For the second flight of the day, I went with DoubleTrouble on a J90 again (thanks to John for loaning/giving me the motor insulator tube ... it's a little worse for wear and tear, but I still have it if you want it back). My theory was that I could leave the delay longer and force the electronic deployment to work. So I thought I cut the delay down by less than an 1/8" (less than 4 seconds), which, according to sims, would still allow for 3 seconds of freefall after apogee, which should have been enough to let the altimeter kick in. 
Flight #3 -
SkyDream #9 (K185-L shaved) Click here or on the photo below to see a 2.8M mpg movie (with analysis) of this flight. O.K. So now it's hot out here. I had wanted to fly SkyDream on a K185 again so I could get some good footage. John had a K185 so I bought it and built it. I'm pretty sure I messed up, and I know how. When I was finished building the motor, I realized (as I had on a flight at LDRS) that I had used the wrong aft closure (one of mine has holes drilled in it for motor retention, and the other doesnt), so I hastily cleaned the aft closure from DT's J90 and replaced the closure on the K185 after I had built it. Either my motor assembly was wrong, or as Andy suggested, about 1 out of 3 K185's has blow by problems, but I had my first motor failure (ever) on this flight. About 3 seconds into the long-burn 7.5 second boost, the motor blew by the fore closure causing separation under boost. Way under boost. In the second picture below (and on the movie) you can clearly see the nose cone and parachute for a split second. 
Flight #4 -
Arreaux #24 (G80-10) Click here or on the photo below to see a 4.9M mpg movie taken from the rocket during this flight. I'd had high hopes about getting a bunch of flights in today but was starting to feel tired by about noon. One of the things I was hoping to do today was a dual launch, filming one of my other rockets from the Arreaux during flight. Also I had rigged a new apogee triggering mechanism and parachute harness on the Arreaux and glassed the body tube, and so wanted to see how they would all work. However, I really didn't want to clean a motor and prep one of my other rockets at that point. So I suggested to one of the club members who was loading his rocket up at the same time that we attempt a dual launch. Below on the left is the Arreaux taking off, on the right is the other rocket a little later. 
I was filmed it from the ground as well, though it's not really worth seeing, as Andy volunteered to press the buttons. I had guessed we needed about 7 seconds from when the Arreaux took off to when we pressed the second button, allowing 2 seconds for the second rocket to start. 
For better or worse, the second rocket took off about 2 seconds after the Arreaux. It didn't really matter that much because the apogee trigger went off at lift off, and instead of a hi-res movie from apogee I got a low res movie of most of the flight. However, the new parachute rigging seems to have worked. By attaching a kevlar thread from the nosecone back to the shock cord, I had rigged it so the camera would point down while under chute. As you can see from the above picture (or from the film, by clicking on the above links), the camera is clearly pointing down while under chute, revealing the roads leading into the area and the flight line, much improved from previous Arreaux-Cam movies. Summary:Well, today was a hot one. I'm not really that dissapointed about SkyDream cuz we build em to fly em, and if you fly em, they're gonna crash! I would have liked to test GPARS more, but it got too hot and there were other rockets, experiments, and things to do today. Thanks to the club and folks that were there to help and share. See ya next month! - Pat |