Last Flight of Burt   

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It was April 4th 2009, up on the FLARE West Mesa launch site. I was annoyed. Gloria and I were going to get a little rocketry practice in. She was going to build an RMS motor for only the second time. I was going to test my Dual-Deployment setup for only the second time.

Gloria had only built a Reloadable Motor once, when she did her qualifying flight in 2006. She earned her Level One certification with the NAR. We don't fly High Power as often as we would like because it is time-consuming to get out the the West Mesa. It takes up most of a Saturday.

I had flown one dual-deployment flight with Burt in March and it went perfectly the first try. Burt had a payload section with a Perfectflite altimeter and two gas discharge baffles for black powder parachute deployments. The Altimeter tracks the altitude of the rocket and may be programmed to discharge an electric current to one or two pyrotechnic devices. I set it up with a deployment after apogee to put out a 16 inch parachute, then again at 800ft as it descended with a 36 inch 'chute. The advantage in this is that the rocket does not drift down range on the wind. The small chute brings it down very quickly, then the larger chute deploys to bring it in for a gentle landing.

File:HappyBurt.JPG
The first flight of BURT was a complete success.

A few of our TARC team members and a friend had come out to see this. I was interested in seeing everything go perfectly. I was annoyed because Gloria had already put together the motor, an I161W, it was loaded into Burt, and I was discovering that there was no launch controller on hand. Lee and Michelle usually bring along a high power launch system. They were at a CPR class instead. Russell had not thought to bring his HPR launch kit. Denzil brought a rail. So, I could possibly launch, but I would have to work with Russell to cobble togeter a controller from an old torn up rig he happens to carry in the truck for spare parts.

A HPR system has a 50' to 150' harness so that you may launch the rocket from a safe distance. Regular launch systems only go out 25' to 35'. HPR systems also have an electrical relay out at the pad because running 12 volts through a 100' to 300' loop of wire often does not provide sufficient current to light off a motor.

If you look closely at the picture at the top, you will see the payload section, with a hole in it for arming the altimeter. Gloria had already put together the motor. You cannot store an assembled motor for more than several hours. The grease used to assemble all of the fittings tightly and prevent leaks through the enclosures will soak into the fuel grains and spoil the motor. Shock from transporting the motor under compression can cause the fuel grains to crumble within the case. You don't store assembled motors, you fire them.

Russell helped me get together a working harness with no relay, and only 35' back. So I walked down range and set up Denzil's launch rail. I dragged the launch controller back from the pad. I then tested an igniter to make sure I had enough current to set it off. It worked. I palmed my screwdriver (used to arm the altimeter) and took Burt down to the pad. As I mounted Burt on the rail, I was again annoyed because the blast plate was missing. This would cause the tail to be sitting right down on the base of the pad where it might set up a vortex which could pull down on the fins and cause the rocket not to leave the pad.

I decided to use the screwdriver to prop the rocket up to prevent this. Feeling clever, I headed back to the launch controller. But I forgot to arm the Altimeter.

I now carry a clipboard and a checklist.

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