Certing Level 2 tomorrow with a CTI K675 Skidmark!! WOOOOOOOOO!!!!

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Orien

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Rocket: Modified 3" LOC Iris
Modifications: Lengthened booster by 12", lengthened payload bay by 6", tailcone, double-wall construction, fiberglass tip-to-tip.
Expected altitude: 8332'
Max velocity: 855mph (Mach 1.11)
Max acceleration: 19 g's
Time to apogee: 20 seconds
Recovery: Apogee deployment via RRC2 with motor backup, 52" chute with spillhole, JL chute release set to 700'. Noise maker and Marco Polo tracking unit onboard.
Onboard Camera: Downward facing Mobius 808 #32 mounted in a 3D printed housing.

Never been this excited about a launch.

image_67232769.JPGimage_50381825.JPGimage_67188481.JPG .
Launch Day shirt selected.
 
Awesome. Way to do it right. Have fun tomorrow.
I've got nine friends and co-workers coming to this. Everyone will have a role and be involved which really makes it fun. NOT in the hands-on flight prep, but tracking, filming, one is bringing a drone, another will work the computer and download the data and videos. Stuff like that. They've never been to a launch.
 
Could that fold be a fin strike? I'm sure there is a lesson in here somewhere....
Good thing they don't make Lamborghini's out of cardboard.
Lol. My conclusion is inadequate material strength. Fully loaded for flight without the motor this thing only weighed 6 pounds. Even with the fiberglass tip to tip and the double wall etc. Open rockets at 19 G’s, which seemed reasonable. But this thing was leaving town in a hurry. Might have been more. Shredded below the Av bay and payload section coupler. That was still connected to the air frame with the shear pins.
 
What does the fin section look like?

Edit: saw you lost it. My guess would be fin flutter.
 
I agree with your conclusion, regardless of the sequence of the events that caused it, the airframe failed. I also failed my first attempt for L2, due to a singed piece of tubular nylon that separated when the main chute deployed.
Each level we attain makes us come to terms with the forces we are dealing with, not only with the motors we fly, but also with mass and momentum during recovery.
I thought I had a pretty good handle on everything when I got my L3, but I later flew a 6" Ultimate Darkstar on an O3400 Imax and got another lesson. Both rail buttons were gone, and the Stickershock decal that I had coated with a generous clear coat had all the leading edges peeled back. o_O
Never quit learning, it will keep you young, even at 70.
 
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