Drogue in HEDD

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Cory

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I’ve used HEDD (head end dual deploy) successfully a few time in a 3” Punisher and have seen many more in various sizes. Usually the main is placed inside the NC and the apogee event separates the NC+Switchband with the avionics from the payload section and the main event blows the NC off the av-bay. My question is has anyone tried putting a drogue in the NC with the main in the payload? It is a tight fit to get a main in a 3” NC for heavier birds, but there is adequate room for a decent drogue. So if I have plenty of room on the payload side why not use it for the main?
I would probably use an extra shear pin on the payload side as the drogue would be pulling directly on them. That pulling by the drougue opening the main early seems the only potential downfall of swapping, but I would like to get some input- especially from any who may have tried this already.
 

mpitfield

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Becasue of where all the laundry would end up, drogue, with shock cord and nosecone above the rest of the package, you might increase your chances of having a failed deployment, where the drogue and nosecone fall through your main. Have you looked at the Fruity Chute Iris Ultra Compact chutes? You could very likely get away with a 36" Iris.
 

Cory

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Becasue of where all the laundry would end up, drogue, with shock cord and nosecone above the rest of the package, you might increase your chances of having a failed deployment, where the drogue and nosecone fall through your main. Have you looked at the Fruity Chute Iris Ultra Compact chutes? You could very likely get away with a 36" Iris.
I see your point - but I’m envisioning a pilot chute type situation if I use a large-ish drogue. Thanks for the input.
I have used a 36 Iris in the Punisher - VERY tight fit with an undersized nomex. Recently purchased the recommended Recon/Nomex and it fits - but not much different in the end.
 

OverTheTop

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This is generally how I fly. Single-ended dual deploy. NC is blown off at apogee (altimeter in NC), with a small drogue attached. Rocket comes down in a controlled manner, but relatively quickly. I try to size the drogue to bring everything in relatively flat. Main is in a deployment bag in the airframe, retained by friction. At main atlitiude (I use 1800') I blow out the bag (altimeters in center of airframe) into the airstream. The flap of the bag has a pilot chute under it which catches the air and pulls the main out. Never had a main at anything other than the planned altitude and never had a tangle. I did have one flight that came in quite hot with the front of the airframe pointing down and the NC sitting nicely in the slipstream at the rear. Main came out and landing was nominal.
 
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