Question about a custom Madcow Batray build

[ManOntheMoon]

I am currently building a modified version of the Madcow Batray where I plan to set up dual-deploy in one chamber in the rocket using redundant Prairie Twister Rocketry cable cutters to deploy the main parachute. The field in my area is 1500'x3000', restricting the maximum altitude to 3000'. The field is very unforgiving with many lost rockets in the woods and dangling in trees. I added a foot to the typical airframe length of the Batray to accommodate the drogue and main parachutes. I plan on using a 24" Ultra X-Type parachute from Top Flight Recovery for the drogue, and a Heavy Duty 60" rip-stop nylon conical parachute with a ~12" spill hole from Public Missiles for the main parachute. I have redundant RRC3 altimeters from Missile Works housed in a 9", 54 mm motor mount tube that is embedded in the nosecone. The altimeters are meant to fire the two redundant cable cutters from Prairie Twister Rocketry that will cut the wire-tie wrapped around the Kevlar protector and main parachute.

I am debating if I should use the altimeters to deploy the drogue or if I should use the motor with a 10 second delay. RockSim simulation with a Cesaroni I345-WT-10 predicts a successful flight ~ 1662' landing less than 100' away from the pad. If I use the altimeters to deploy the drogue, I was thinking of putting the charge in the front end of the rocket close to the nosecone in a finger of a latex glove. My concern is that the charge will blow out the nosecone, but further embed the two parachutes in the chamber. I have attached my RockSim design for reference of the design.

Does anyone have any empirical data supporting using the altimeters vs. using the motor to deploy the drogue? Are there any other recommendations I should consider for my design?View attachment batray30_TD.rkt

 

[dixontj93060]

The way you are approaching the charge placement is safer, but I have done it both ways and been fine.

 

[Nick@JET]

Is this a 4" super Batray or the standard batray? I would fly drogueless if the field is that small - that is a pretty big drogue and a big 60" main - also might consider it it is that big - opening main at 500.
I'm running a 4" super Batray cardboard that is extended for DD so an extra 18" long drogueless on a 48" main slightly reefed (but will pull the reef on harder landing areas) and it falls pretty straight. For your reference mine flys to I-170 - 1692' , H152 -1100', H195 - 800'.
Also you mentioned your charge actually pushing the chute in the nose cone - I would be real careful with that, might think of how you place your charge and place your recovery gear so it will pull out. Using the Alt to fire the drogue is so much more accurate to happen at Appogee. I can speak to the cable cutter since I've never used one.
Good luck - post some pics!

 

[ManOntheMoon]

Thanks for the replies.

[Is this a 4" super Batray or the standard batray?]

It is a 3" Fiberglass Batray.