- Jun 19, 2017
- Reaction score
Last September, I tried the "Python" two-stage flight at Airfest. It didn't go well, with the motor finally coming up to pressure just after all of the chutes blew. It was not a good flight, but I repaired everything and finally got a chance to repeat the flight over the weekend. It went pretty well, except that part of the flight was not visible due to a cloud, and I also didn't get all of the planned video. Still trying to figure out what happened there. Anyway, copied below are two YouTube video links. One is of the entire flight and the other is a zoomed-in version where it's a bit easier to see what the rocket was doing.
I posted some data in the first video showing how the rocket generally followed the flight plan with respect to tilt and bearing. Not perfect, but not too bad.
One thing you can see in the videos is that the rocket motion wasn't all that smooth, particularly when the rocket was turning upward against gravity. I think part of the reason for that is that I allowed more time for those turns due to uncertainty in the turning rate when turning upward. I think I allowed too much time. Since each turn is a discrete step, having too long of a step makes the turn look less "continuous". The other thing that I noticed in the data was that the canards never reached the limit of their travel range. I have them set up to turn proportionally up to 7.5° for angle errors up to 7.5°. The steps in the flight program were at 4° increments, and the canard angles never exceeded 4°. That means that the rocket never "fell behind" the flight program. I was concerned that it might fall behind in the upward turns, but that didn't happen (and in fact, the opposite happened).
I managed to break a fin on the spin can again - crap. I suspect I will fix it at some point, but it may be a while before that happens. In the meantime, there should be some beta group flights coming up over the next few months!