Public Enemy Performer DD Question

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Swampworks

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Eyeing one of these for an L2 bird and would like to go with dual deployment. Looking at the original specs, the dual deploy kit/model was 8 inches longer than the non-dual deploy. With only an 18" drogue chute to add, I am wondering why it would need to be longer. The overal length (non dual depl) is 70". Seems like such a small chute would easily fit into the lower airframe, or am I way off base?

I guess what I am trying to figure out is if I can simply add the e-bay and the main chute, or do I really need to extend the tube.

Any help?
 

mattvd

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Maybe I am missing something in your question, but . . .

If you have the booster section -- with the drogue chute packed in there . . . .
And you add the e-bay on top of that . . . . to deploy chutes above and below the e-bay . . . .
Where would you put the main chute?
You need something between the e-bay and the nosecone to pack the chute and extra shock cord into.
 

Swampworks

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My thought is that the airframe is made up of 2 tubes. I can see the bird being built out of a single tube, right? So, booster section has drogue chute. Upper section has main which is ejected through the "top" (nose) end. That's how I have seen most DD's work.

Maybe I am missing something.
 

Handeman

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I went to look up the model specs. and got this from the website

Sorry Folks But Do to Illness the restarting of



Public Enemy Rockets have been Cancelled.



Thanks For all the years of business.



3/6/2009

To answer your question, the electronics bay will/should take up 2 times the diameter of the rocket. Eight inches if it's a 4" rocket. If you have enough room for the main, drogue, two (2) sets of shock cords, and the "8"inches of electronics bay, then you shouldn't need to lengthen it.

I don't know what MMT is used, but if it's 54mm, then you can have cases almost 30", the nose cone is probably in the 18 - 22 inch length (including the shoulder) with 8" of electronics bay, that could be 60". Would only leave 10" for main and drogue recovery, Not much space.
 

Swampworks

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Thanks! I guess the numbers don't lie. I suppose I need to break out the rocksim file and look at the component lengths and make the decision.
 

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