Static Ejection Testing

Ground-test!

If you're using electronics, put the ejection charge in place, with the wires leading out of the airframe. With that size rocket, you should be able to hold the airframe in your hands, angled away from you, turn your face away and have someone set off the charge.

A better way is to use a launch controller to set off the charge, so you're farther away.

-Kevin

Ok let me clarify,

If I ground test, figuring I fixture the lower part of the airframe,

2) If I manually wire the charges, how far should the charge separate the airframe components?

Al, sigh ... its not that complicated ... believe me man ... been there done that at least 30 - 40 times ... look dB will not be required for this one :) Just do what the dude , Kevin, suggested. If loud reports scare you, then set the thing in a trash can, and use 30 feet of wire to set off the charge ... look you are not von Braun, Al ... so stop trying to play the role. Just fibre glass, epoxy, spray paint, and go fly ... no Static test, jigs, test stands ... what the f*ck are you thinking Al??? This is TOY rocketry ... you are not sitting there calculated Specific Impulse, heats, reaction co-efficients ... man just slap those high powered kits together and have some fun!

Oh you need to account for altitude ... the higher you go, the greater the amount of gas volume you will need ... its really trial and error ... now have fun with that!

Don't you be a roo too, stay in school ... don't be a Skippy fool!

Hold the rocket or payload section away from you like a mortar, have someone fire it with a launch controller. This will work well for 4" rockets. You would want to fixture it somehow if it was a larger airframe though.

Enough to get to the end of you recovery harness, or close to it. Not so much that it snaps back. Check InfoCenral on ROL for calculations to select a charge weight to start and work up from. Depending on recovery harness length, I'd start at 1.5 to 2.0 grams on a rocket like yours. Make sure you have your recovery system configured as you would use it in-flight. (parachute(s), harness, blastshield(s) shear pins)

What kind of altimeter? Ground test mode on the Missile Works RRC2 works for me. Alternatively, you could install it in your alt. bay and apply vacuum with a large syringe.

Build a mock airframe. Measure the ejection charge into plastic bag. Insert Davey fire seal bag around Davey fire. Place charge in airframe. Load recovery laundry or mock payload bay. Connect to Estes launch controller and 5,4,3,2,1

It can make the neighbors angry as testing is quite loud!