Zeus-cat
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There have been claims that ejection charges do not eject parachutes; rather, they push the nose cone off and the nose cone pulls out the parachute. I decided to test that theory.
I used seven old dual deploy ejection charges for the test. I installed the ejection charges in a used D12 case and ran the wires out of the nozzle. I had to widen the nozzle slightly to make it easier to run the wires. I inserted the motor into my old beat up Estes Phoenix (BT-80) which is no longer flyable. I inserted a 12” x 12” Nomex chute protector, then the parachute and then installed the nose. None of these were connected to each other so if the chute was ejected it had to be from the ejection charge.
I laid the rocket on the ground and put a brick under the forward section to elevate the nose slightly. I connected each charge to my launch controller and pushed the button.
Two of the charges showed very high resistance and failed to fire.
Two more fired, but were very weak and failed to dislodge the nose cone.
Three charges fired and ejected the nose cone. Two of the ejections were weak and the nose cone only flew off about a foot or so. However, in both cases both the Nomex and chute were cleanly expelled from the rocket. The third charge was much more powerful and fired the nose about six feet. The chute was ejected about three feet, but the Nomex hung up in the top of the body tube.
While certainly not an exhaustive series of tests it certainly shows that the ejection charge will eject the parachute without the nose cone pulling it out.
I used seven old dual deploy ejection charges for the test. I installed the ejection charges in a used D12 case and ran the wires out of the nozzle. I had to widen the nozzle slightly to make it easier to run the wires. I inserted the motor into my old beat up Estes Phoenix (BT-80) which is no longer flyable. I inserted a 12” x 12” Nomex chute protector, then the parachute and then installed the nose. None of these were connected to each other so if the chute was ejected it had to be from the ejection charge.
I laid the rocket on the ground and put a brick under the forward section to elevate the nose slightly. I connected each charge to my launch controller and pushed the button.
Two of the charges showed very high resistance and failed to fire.
Two more fired, but were very weak and failed to dislodge the nose cone.
Three charges fired and ejected the nose cone. Two of the ejections were weak and the nose cone only flew off about a foot or so. However, in both cases both the Nomex and chute were cleanly expelled from the rocket. The third charge was much more powerful and fired the nose about six feet. The chute was ejected about three feet, but the Nomex hung up in the top of the body tube.
While certainly not an exhaustive series of tests it certainly shows that the ejection charge will eject the parachute without the nose cone pulling it out.