PSAS/ news/ 2009-04-05 - Drop test of recovery system.

It was a beautiful day for a drop test, that's for sure!

Western Oregon Farm

Setting up the Night Before

A bunch of us headed out to a farm in western Oregon to test the recovery system. With the land-owner's permission, we dropped the recovery system (nosecone, separation ring, parachute system, recovery module) and a 9 lb. weight to make sure we had at least 20 lbs. of force of the system.

Everything went very, very well logistically speaking. The test itself, not so much. The LPC2148 microcontroller board we used to measure the pressure from a SCP1000 pressure sensor and actuate the separation ring and line cutters got reset right as it was tossed out of an airplane. Since this wasn't a "production" flight computer and we wanted to get this system tested ASAP, we didn't bother with writing the current state to flash... so on reset, the board went into a "ready" mode which is a safe state before we arm it. And we know the board was reset after it was in the airstream because if it was reset in the plane, then it would have instantly gone into armed mode since it would have still been plugged into the arming plug.

Thus, our test system hit the ground at quite a clip.

First look at the impact

Close up of the damage

Another close up of the damage


Here's the raw data and here's a spread sheet drop-data-2009-04-05.xls of that pressure/altimeter data which was recorded in the plane right before the system was reset. Here's the graph from that spreadsheet:

Graph of the altitude vs. time of the drop, and a simulated free fall.

And finally, here's a beautiful 300fps video of the drop.