"Back in Black" at MDRA Red Glare 8 (VIII) - Onboard HD Video

This is my Hawk Mountain Enterprises Talon-3 rocket named "Back in Black", flying on an Animal Motor Works L-1300 engine at MDRA's Red Glare VIII event on April 17th, 2010 at approximately 12:30 PM. The rocket is 7 feet 6 inches long and 3 inches in diameter, weighing ~17 pounds loaded and ready for launch. It is equipped with an R-DAS altimeter and a 720p HD camcorder in the avbay and a BeeLine 433 MHz tracking beacon in the nosecone. This flight was successful despite some setbacks. The first occurred when the rocket was loaded onto the pad. When the altimeter was activated it remained silent - there was no initialization tone. The rocket was returned to the preparation area and disassembled for inspection. The cause was determined to be a bent terminal on the 9V battery. It had not snapped fully into the holder because of this, and was making contact only intermittently. I am SO glad it failed to make contact at that moment (when I switched it on). Had it made contact and I had heard the init beep from the altimeter the launch would have taken place, and I am convinced that the power to the altimeter would have been interrupted during flight - resulting in catastrophic loss of the entire rocket. After repairing the problem, the rocket flew successfully on the second try. The thrust curve says that the L-1300 develops more than 340 pounds of thrust for the first 1.4 seconds or so of the burn. According to the altimeter graph, this accelerated the rocket at more than 20G (26 at one point) to a peak velocity of just over Mach 1 at ~6000 ft., after which it coasted on up to a 10,629 foot apogee. If you watch the exhaust plume carefully right at burnout (between 7 and 8 seconds into the video) you will see some material being ejected through the nozzle. I am told that this is probably the casting tube from the aft-most propellant grain (at the nozzle end of the motor) being ejected after all the propellant in that grain was consumed. There were two events, perhaps two grains did this. The streamer at apogee was something new for this flight, in previous flights I had always gone drogueless. The streamer was expected to make visual tracking easier. I used a kevlar chute protector to prevent the BP charge from melting the streamer. The streamer was not secured to a single point on the shroud line and so it shifted position - fouling the shock cord and streamer as can be seen during the descent. As a result of being tangled up like this, the booster is way too close to the altimeter (where the camera is located). It looks as though no contact was ever made between the two sections during the freefall. After separating into 2 pieces at apogee, the rocket tumbles down to 600 feet, where it kicks out the main chute - a Rocketman R7. This seems a wee bit small, I'd prefer a slower descent under chute, but I've yet to figure out how to safely pack the R-9C into this narrow airframe. It was a safe landing, that's what matters. No damage at all. The altimeter is heard at the end of the video beeping out the apogee. There is a low tone indicating "start", then one short tone (1), one long tone (0), six short tones (6), two short tones (2), and nine short tones (9) - 1..0..6..2..9.. = 10,629 feet. The camera used was a cheap one I bought on EBAY, an SVP model T-100. It shoots 720p HD video for 45 minutes at a whack, and can hold almost 3 such movies in its internal memory. The camera is not "rocket friendly", the controls cannot be relied upon (sometimes they do not make when pressed, sometimes they bounce etc.), and there is no way from outside the rocket to know if it is recording or not. So it has to be started at the prep area as the rocket is being assembled. This means the video is recording throughout the portage to the RSO table and up to the pad, then throughout the wait for launch. It recorded 30 minutes of weird stuff before launch and about 13 after recovery while lying on the ground. It just happened to be facing the launch pads and recorded two big launches while it was waiting for me to get to it. I have two large unedited video files, one from the failed attempt and one from the successful one. I hope to edit some of that extraneous video into a montage and post it when I'm done.

 Rocketry Club: Maryland Delaware Rocketry Association

Author cyberia55
Duration 230 seconds
Rating Best

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