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- Test location: Minute Man Airfield
- Configuration:
- Parachute connected to test rig attached to car to raise the parachute up higher, out of the car wake
- Prototype test rig:
- New tow test acceleration method:
- For an automatic clutch (and because these tests are on tarmac now), put the car into drive and step on the brake
- Rev the engine to 3-4k rpm (maximum power band for most engines) during countdown
- At the same time, floor the gas pedal and release the brakes
- Ideally this gets a faster start because the car can apply more power at the start and accelerate better, as opposed to starting from 0 RPM and revving higher before hitting max power
- Run 1:
- Proving test rig, full parachute deployment from bag but no reefing line
- Got up to approximately 50 mph before the line ran out, parachute came out of the bag as expected
- Shock force of full parachute at 50 mph was enough to deform the test stand and loosen the fixture to the truck
- VIDEO: towtest21mar_run1.MOV
- Test was halted immediately, no damage was noted to the parachute or the truck
- Run 2:
- Modifying test rig, ran a ratchet strap across the truck bed and then connected the (not reefed) parachute lines to that ratchet strap and up over the tailgate
- Again, got up to approximately 50 mph before deployment, this time the shock force also immediately snapped the ratchet strap (rated to 500 lbf)
- VIDEO: towtest21mar_run2.MOV
- Test was halted immediately, no damage was noted to the parachute but the hooks in the truck bed were slightly deformedÂ
- Run 3:
- Instead of testing parachute deployment at high speed, test the reefed parachute at low speed
- Drive at about 20 mph (fast enough to inflate the parachute but no faster)
- Attempted to ignite the line cutter remotely using a laptop and the telemega (did not succeed)
- Also did not manage to ignite the line cutter with a lipo battery (so some continuity issues with the e-matches in the line cutter)
- Results:
- Tow testing successful! Parachute emerged from the parachute bag with no issues
- If we run tow testing again with a test rig like this, we will need to do more calculations to build a sturdier test stand
