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2.60" BT - 4x E Cluster - 4FT Tall Rocket - Name: 4X4

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mjstech

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Nose 8 3/8"
2x 18" BT-80
~48" tall including swept back 3/16" Balsa fins
The (3) fins will be 'upsized' of the Initiator style
32" parachute
2x 1" 1/4" lugs
I have the motor mount glued in here

I got this from unclemikesrocketshack '4xE'
Here it is glued up minus fins

Here is the planned parachute

I plan on having this done for Jan 9th launch.
The rod will be very long 5-6FT
Remote launcher will be 12V car battery fused.
Any thoughts/tips? How do you like the name 4X4?
 

Bill P

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4x4 would be a good name if you staged 4x to 4x.

:hohoho:
 

mjstech

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Yeah, Tim Taylor it.. More Power! Hah 4X D12-0 to 4X E9-6 = 182 total N/s. Would make for expensive flights. I wonder how hard it would be for the E uppers to all fire. Has anyone done 4xD to 4xE?
 

Pantherjon

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Pretty cool:cool: Not a true 4x4 tho, for that it reqiures 4 engines and 4 fins!:roll:
 

bobkrech

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mjstech

You do realize that putting (4) E9 motors in a rocket makes it a high power rocket requiring a written FAA waiver to launch it and requires the user to be L1 high power certified by either NAR or TRA.

The FAA limits for a model rocket are: weight not to exceed 1500 grams and total propellant weight not to exceed 125 grams. A E9 has 35.8 grams of propellant, so (4) motors have 141.2 grams which is over the FAA and NAR and TRA high power certification requirement limits. http://www.nar.org/SandT/pdf/Estes/E9.pdf

Bob
 

JRThro

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mjstech

You do realize that putting (4) E9 motors in a rocket makes it a high power rocket requiring a written FAA waiver to launch it and requires the user to be L1 high power certified by either NAR or TRA.

The FAA limits for a model rocket are: weight not to exceed 1500 grams and total propellant weight not to exceed 125 grams. A E9 has 35.8 grams of propellant, so (4) motors have 141.2 grams which is over the FAA and NAR and TRA high power certification requirement limits. http://www.nar.org/SandT/pdf/Estes/E9.pdf

Bob
Good point, Bob! A lot of people, including me, often forget the limit on propellant mass.

Two Estes E9's (35.8 g of propellant) and two Estes D12's (21.1 g of propellant) would do the trick, though, for a total propellant mass of 113.8 g.
 

patelldp

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mjstech

You do realize that putting (4) E9 motors in a rocket makes it a high power rocket requiring a written FAA waiver to launch it and requires the user to be L1 high power certified by either NAR or TRA.

The FAA limits for a model rocket are: weight not to exceed 1500 grams and total propellant weight not to exceed 125 grams. A E9 has 35.8 grams of propellant, so (4) motors have 141.2 grams which is over the FAA and NAR and TRA high power certification requirement limits. http://www.nar.org/SandT/pdf/Estes/E9.pdf

Bob
Dumbest. Rule. Ever.
 

mjstech

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Thanks for the information Bob!
If I need a level 1 cert I will hold off on launching this with 4xE, and may do what John said above, 2xE and 2xD, or just use all my spacers and run with 4xD12. I was planning on attempting a L1 in Feb or March anyway.
The waiver for the site is 7500 ft, with a call-in waiver to 12,000 ft.
I may still run 4 fins(for stability) as Pantherjon said. 4 motors, 4ft tall, 4 fins. Thanks for the information. I also liked the easy to understand information on this site/pdf. http://www.doug79.com/stuff/HPR_metric9c.pdf
 
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