Water Rocket Pendulum Parachute Recovery Idea Fail

Yet another idea I tried for parachute deployment that didn’t work for me. The theory I had was that with enough weight hanging down on a pendulum it could keep a shaft holding stationary but as the rocket begins turning horizontal at the apogee a catch that was holding back a vertical piece from the shaft would release as the catch position changed. Hopefully the pictures I provide will explain this a little better.  There was a spring over the horizontal shaft that pushed the shaft to one side which released the nose of the rocket that had tension on the opposite side from rubber bands.

It was another one of those prototypes that appeared to work fine in a slow motion test on the ground but not so well in a high speed launch.  One good thing, I really got a nice picture of the liftoff of this rocket. The parachute did come out, trouble was it was only about 35 feet high when the parachute deployed.  How the parachute deployed was the forces at launch caused the mechanism to rip out where it was fastened and this pulled in the pin that was holding the nose on the rocket.

Mechanism to release pin holding down rocket nose

At first I was tempted to try to repair the damaged parts but the more I thought about the idea I thought there must be a reason I had never seen anyone else try this method.  The amount of weight that I had on the pendulum was more than I had thought I would need also.  With less weight it would not activate and retract the pin holding the nose down.

Ended up with so much weight on pendulum

Yes, another failure but I still think I learned something and had fun trying.

Rocket came down fine

This video explains why the idea could not work:




Bill Kuhl
http://www.scienceguy.org