Need Review: Lots of Mods to A Kit, Little John

This was a madcow Little John paper rocket, 38mm motor. After a number of flights, amputations and application of fiberglass to the top for repairs, I want to convert it to a dual deployment rocket to practice so I can get the hang of electronics and dual deployment before I buy a large rocket. The rocksim file has these changes and see my questions.

-Started with the original madcow rocksim file.
-Added a coupler with bulkheads for altimeter. Copied the specs from another madcow design for these parts.
-Added an 18" section on the nosecone side. Copied the specs from another madcow design for this
-I changed the mass to the current weight, plus an estimation of the new parts, no motor.
-I have not calculated in the hardware and sled/electronics yet to the mass.
the modified rocksim file is attached

Questions:
Anything obviously wrong, like the length and the CG to CP? Is TOO over-stable bad.
Is my general methodology correct in how I am approaching this?

thanks in advance for any advice.

View attachment Little Jon with Mods for Dual Deployment Version 1 sept 2 2103.rkt

I design a very special coupler that add only 8" to my Madcow Fiberglass Little John , it's only to add the altimeter as I will use a charge for apogee and a cable cutter for the main. I don't want to add to much lenght as the fins are small. I will take a pic tomorrow as my shop is close now. As you can see on the pic , my CAL is 1,27

The only thing that grabs me is move your parachute to the upper body tube and ad mass for the altimeter.

How did it turn out? I added a 12" section and the removable Madcow Ebay kit which is identical to the one I am using in my Patriot. It adds 15.5oz with battery installed. Cant remember the Stability off the top of my head, but I will attach my sim file when I get home, but with motor I'm thinking its around 1.3-1.5.

Natty, Here's my file.

View attachment The Riddler Dual Deploy.rkt

Good, I just did the third launch and this time I did a cert for level 2 with a J357 see this video; https://www.youtube.com/watch?v=e9IfYvLlc_U&feature=youtu.be

Awesome! Any Flight Data?

View attachment Jan 11 cert flight level 2.pdfView attachment Little Jon with Mods for Dual Deployment Version 1 sept 2 2103.rktView attachment Little Jon with Mods for Dual Deployment Version 1 sept 2 2103.rktI attached 2 files, one is the rkt file and the other is the pdf of my level 2 cert grapy from yesterday.

dgreger said:

Awesome! Any Flight Data?

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