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Old 12-31-2008, 09:50 PM
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snaquin snaquin is offline
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Join Date: Jun 2005
Location: Louisiana
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Default New Plan -- KE-4 EnerJet Egg Crate

I'm looking over some of my older RockSim files updating with version 9 and ran across this one that was detailed in a build / fly thread I started three years ago that Craig & Scott had mentioned might be a good BARCLONE candidate. I'm also refining a few other EnerJet builds that I have RockSim files for and I'll post those as soon as they are finished.

The Egg Crate model I built was based on LT-125 tubing and was modified to fit the egg capsule to the airframe tube. The RockSim file posted below is for a Semroc ST-13 version, like the original and features an accurate fin pattern that John Dyer posted when the build was being discussed. I also posted a file that uses a 24mm adapter if you're not looking to fly all out with 29mm motors.

Pay attention to the Egg (mass object) in the design. It is noted in the original EnerJet instructions that the model was designed to be flown with a minimum payload of 1-1/2 ounces for adequate stability. This is important as I noted this to be true with a built model CG/CP as well as some of the RockSim stability estimations ..... it needs the weight. Check your stability before flight! Original model was designed especially for NAR egg lofting competitions and could be flown on the E24, F52 & F67 EnerJet motors.

Build / flight details for my LT-125 version are in this thread:

http://forums.rocketshoppe.com/showthread.php?t=621

I have another RockSim file for a version using all Semroc parts including a balsa nose cone / balsa transition with the parts on hand to build it however I didn't post that file because although it would make a nice replica it would be useless as an egg lofter due to space limitation in the short ST-20 due to the solid balsa parts. If there is interest I'll dig it out and post it.

Length: 22.06"
Diameter: 2.04" (Egg Capsule), 1.34" (ST-13 / Airframe)
Span Dia: 5.96"
Weight: 5.18 oz (Including 2 oz Mass Object - Egg)

Thanks!
Attached Thumbnails
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Name:  EnerJet Egg Crate KE-4 ST13 29mm.jpg
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Size:  10.5 KB  Click image for larger version

Name:  001 EnerJet Egg Crate LT125.JPG
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Size:  98.0 KB  Click image for larger version

Name:  002 EnerJet Egg Crate LT125.jpg
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Size:  186.4 KB  Click image for larger version

Name:  Screenprint EnerJet Egg Crate KE-4 ST13 29mm.jpg
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Size:  122.2 KB  
Attached Files
File Type: rkt EnerJet Egg Crate KE-4 ST13 29mm Corrected Fin Pattern v9.rkt (77.1 KB, 203 views)
File Type: rkt EnerJet Egg Crate KE-4 ST13 24mm Corrected Fin Pattern v9.rkt (32.1 KB, 205 views)
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