PSAS Launch 13 & 13.1 - LV3
Recovery Team Member:
The Portland State Aerospace Society (PSAS), is a university rocketry and satellite group at Portland State University (PSU). PSAS builds and flies high-powered amateur rockets and nanosatellites with a legacy of innovative, student led projects.
When I joined PSAS in January 2018 I began working on the Recovery Team in preparation for Launch 13, which was scheduled for May of that year. Launch 13 was performed using PSAS Launch Vehicle 3 (LV3). The recovery system on LV3 consisted of components from multiple previous Mechanical Engineering capstone projects at Portland State, including the Electronic Nose Cone Separation Ring (eNSR) designed in 2015 and the Pyrotechnic Line Cutters designed in 2008.
The goal of the recovery system is to separate the nose cone from the rocket in order to deploy a series of parachutes, allowing the components of the rocket to return safely to earth.
In preparation for Launch 13 I repeatedly performed:
assembly and ground testing of the Electronic Nose Cone Separation Ring (eNSR)
folding and packing of parachutes, tying knots and packing cords and webbing.
inspecting parts for wear or damage
writing standard operating procedures (SOPs)
assembly of pyrotechnic line cutters
cleaning and maintenance of line cutters between firings
Line cutter blade manufacturing and testing
Based on a 2008 Mechanical Engineering Capstone for Launch Vehicle 2 (LV2) the Pyrotechnic Line Cutters were used on both LV2 and LV3 to separate the drogue parachute from the rocket. The line cutters operate by firing a small bullet with a sharpened blade through the parachute line as the line passes through the line cutter assembly housing. The blade is fired by a small gun powder charge. During preparation for launch 13 the blades were failing tests; they were re-sharpened to an incorrect angle and ceased working correctly. I was asked to manufacture new blades and to perform repeated reliability testing on them in preparation of Launch 13.
I manufactured new blades according to plans using a bench grinder, metal lathe, small bench top mill and drill press.
On site launch assembly
Launch 13 and 31.1 launch vehicle 3
In May of 2018 LV3 was launched from the Oregon Rocketry launch site in Brothers, Oregon. A previous attempt in April of that year was scrubbed at the last moment when a lug on the rocket that travels along a guide rail broke off.
The entire system was set up on-site at both launches, following our pre-determined SOPs. The majority of set-up was done the night before the launch and final details were completed the morning of. The recovery system requires complex set-up, including line cutters with pyrotechnic charges, electronic nose cone separation ring assembly, correctly packed parachutes and lines/webbing, surgical tubing ring, and nose cone. The entire assembly must be constructed in proper order with the parachute lines running through system correctly so they will perform a sequence of events correctly, be severed when needed, and not get tangled or snagged during deployment.
Unfortunately the rocket experienced an unscheduled rapid disassembly and the recovery system was unable to be deployed before the entire system was destroyed.