Aerotech insulator burn-through?

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Well-Known Member
Nov 22, 2014
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New to Aerotech RMS here. Flew a G76-7G this weekend and finally got the rocket back. I noticed that the insulator tube inside the casing burned through; there's a burned line going about a third of the way up the insulator tube, presumably corresponding to the slot in the motor. Is this normal? If not, should I be concerned about any damage to the case?
That's pretty much normal for me. I started putting a thin coating of grease on the outside of the liner to make it easier to clean.
Some of the cooler motors shred that liner a bit less, but the g76 does it every single time.

As long as the motor tube is smooth and not bleached out you should be in pretty good shape.
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Every G76G I flew had the liner burn through at the bottom. I've never had any casing damage from it though.

The green propellant burns really hot. That's just the way it is.
Exact same thing happened to me with the G76. I'll be scrubbing out the case and inspecting, and greasing it better next time. (There will be a next time)
I bought my first 29/40-120 motor in 2003 and have been flying it since. I usually fly G64Ws but have tried all of the other available loads over the years. I get burn through or split liners every few flight and have been getting that since '03. I stopped greasing liners in 2004 because I used Vasoline the whole time and it seemed to make liner removal worse when using it on anything more than the threads and o-rings.

The burnt or split liners in the 29/40-120 case are pretty normal and nothing to worry about.

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