As you can read in the design pages "in the parabolic flight description" an air-flap release although simple
has some disadvantages. Not triggering during parabolic flight is the main disadvantage. Also here is shown that timer mechanisms can do a good job and that a very accurate timing
is not required. As i intend to make my future flights go higher and more susceptible for a non triggering chute release i changed over to a mechanical timer mechanism. Found on
the attic an old mechanical timer for the shutter release of a camera (from before the era that these things went electronic). Old but reliable.
Made with this timer my timed chute release mechanism.
First a drawing of the principle in sideview.
The timer, at the end of its delay, pushes a pin outwards. This pin on its turn releases a rubber band, this rubber band holds the top container with the chute by a sort of tie wrap
release mechanism. This is the same as i used with the air-flap and has proven itself. The start trigger is with a weight on a wire, the acceleration after launch starts
the mechanical countdown.
Below first a picture of the timer itself.
Then a picture mechanism of the rocket head with chute bay (no chute in head) and a video to see the timer in action. There is no chute in the chute bay so that is why
after release of the tie wraps the nose stays on. With chute rubberbands push the chute out and the nose cone away from the rocket.
