Advice on 1st flight of Amraam 4

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rvanstone

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Folks,

So my Amraam 4 is about to be completed and the 1st flight is fast approaching.
The question the rockets never been tested or should I say that the "Copilot" never been tested .
So how do I approach the 1st flight ?
Trust the fact that the Alitimeter will fire the speration charge and chance a lawndart ?

Ron
 
I got my AMRAAM4 done not to long ago and I hope to cert with it in Oct.
 
Bowhunter
So what cert level 1 or 2 ?
Has your Amraam had its first flight yet ?

Ron
 
If you want to try your electronics while still making sure of a return you may want to go with a Pro38 or 54 using motor ejection. Do your electronics as if there was no motor ejection. This gives you the chance to listen for your cannons to fire and be able to check in post flight. If it's a dual deploy the motor ejection with do the first step (along with your 'backup' electronics) and your electronics will be solely responsible for the main. Bottom line you still get the rocket back and you can check your electronics to see if it all fired properly.
 
Originally posted by Chuck Rudy
If you want to try your electronics while still making sure of a return you may want to go with a Pro38 or 54 using motor ejection. Do your electronics as if there was no motor ejection. This gives you the chance to listen for your cannons to fire and be able to check in post flight. If it's a dual deploy the motor ejection with do the first step (along with your 'backup' electronics) and your electronics will be solely responsible for the main. Bottom line you still get the rocket back and you can check your electronics to see if it all fired properly.

To take Chuck's excellent suggestion one step further for that first flight, be sure to put your *main* chute in to deploy at apogee & the drogue at low altitude. That way if something goes wrong with the electronics, you will still safely recover the rocket. (You just might have a bit of a walk to get it...) If the drogue ejects then you know everything worked. Assuming everything does work properly, swap the chutes, load up another motor, & let 'er rip! :D

HTH,
 
Chuck,
I was think abou that it means thou I will have to alter the AFT section wth baffle holes to have the motor ejection work


Ron
 
I was just going to mention that Ron; the fin can has a bulkhead capping the coupler. What I would suggest to you is to ground test your altimeter. You can do this with any old wide mouthed bottle. Some of these new sport drinks have such a bottle, as do bicycle water bottles and some others found in housewares at your local store. A piece of aquarium hose or R/C Airplane hose can be used as a vacumn hose. Drill a hole in the lid for the hose and one for ignitor wires.

You can use cheap Estes ignitors for the test so you can save your e-matches for the launch. Remember that, do not try to hook up ignitors to the altimeter as it will probably not fire them. Hook up the outside wires to a couple Estes Ignitors or matches, then turn on your altimeter, drop it in the bottle and tighten the lid. Suck on the tube as much as you can to create a vacumn and hold it, watching for the first match to light, slowly let out the air to see if the second match fires and your ground test of the altimeter is completed.

Make sure the pistons move freely inside the bodytubes. Sand them if they don't...they should be able to drop in the tube smoothly under their own weight. To strengthen the pistons, I "double walled" them, using a 4" PML phenolic coupler I purchased extra. I cut it lengthwise, then wrapped it around the inside webbed cord and squeezed it to fit inside the piston. I then cut it to length and epoxied the second "Wall" inside the piston. One coupler was enough to do both pistons. This will make it much sturdier and allow you to sand more if a better fit is needed.

Use around 3/4 gram of black powder in the lower/apogee section and around 1 - 1 1/4 grams in the upper section for the main chute and the rocket will seperate fine.

Good luck and keep us posted.

Carl
 
Doesn't the co-pilot have a ground test mode? I can't find my documentation, but I think it does. This would prove that the co-pilot can fire the igniters, and that the BP charges will deploy the parachute(s).
 
Originally posted by rvanstone
Chuck,
I was think(ing) abou(t) that it means thou(gh) I will have to alter the AFT section wth baffle holes to have the motor ejection work


Ron

You know your rocket better than anyone.....if the suggestion works, by all means try it, otherwise redundancy is another workaround. My little guy used my suggestion a couple weeks ago to check his dual deployment skills, he passed with flying colors. Since battery connections under boost can be a large issue ground testing is nice, and tells you if the unit works, it is not real world. Plus a big baffle hole (about the size of the motor) makes it easier to use the longer hybrids. :cool:

Good luck.



Chuck
 
Originally posted by rvanstone
Folks,

So my Amraam 4 is about to be completed and the 1st flight is fast approaching.
The question the rockets never been tested or should I say that the "Copilot" never been tested .
So how do I approach the 1st flight ?
Trust the fact that the Alitimeter will fire the speration charge and chance a lawndart ?

Ron

I would most definitely test out the altimeter. You can either ground test or air test. For ground testing you can either use the built-in ground test routine that many altimeters have (check the manual) or find a vacuum chamber. Use a couple of actual low current e-matches to be sure that the altimeter will fire them.

My personal preference is to air test the unit. Fly it with no other responsibilies other than just proving itself to work. Hook up a couple of e-matches and see if they are fried.

I am also a fan of redundancy.

Murray
 
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