I put an Aero Tech G80-7T in my rocket today. Installed the copper
head supplied. Hit my ignition button. It smoked lightly like it was ready
to ignite. Then "POP". The propellant blew out the bottom. Broken plastic
shredded the bottom of my rocket. It looks like a cartoon shot gun.
The engine mount contained the explosion well. Only two punctures
could be seen from the outside.
I have 24 pieces of G80-7T
I have used many Aero Tech motors and have had no problem.
What happened?
Thanks MikeS
Sounds like you had a CATO. File a MESS report and contact Aerotech - they'll hook you up with a new motor (the MESS report is so that they can keep track of failures).
Aerotech has several bad batches of G80's early this year. John Wilke, a club member who was helping out the TARC team had multiple G80 CATOs from a batch in January. Kids were bummed out to say the least watching several of their birds go boom...
Aerotech will replace them. Save the pieces.
Warren Musselman
Indeed, contact Aerotech. THey are slow, but they will replace.
I believe the bad G80s are MUCH more widespread than AT will admit....
I've flown four w/o incident and seen 2 others do well, but I know its a big issue. Just hope the sss contest isn't stained by same. Obviously, tho not written into the rules, is in the event of a cato, sss entrants gets a second shot. If it happens in dec?? Taking precedent from last year, I suggest fly then at your own risk. No second chance. Also if theres a forum sticky where we could post lot numbers or sources of G80 catos, may be helpful.
J
Excellent idea. I do believe at one time John Wilke told me the lot numbers he had problems with. John?
Warren
First of all, with regard to CATOs... last year, anyway, we specifically said that if there were a CATO in your SSS you were outta luck.
Regarding this year's CATOs. I decline to disclose, it is a trade secret.
KIDDING!!! Had 'ya thinking, though, didn't I??
The bad lot I got into was 010405. 3 of 4 motors of that had violent CATOs, and the 4th motor was way lame...
JW
Oh, great. I can't remove my motor except with an X-Acto knife after the flight, which is Warren's option and part of the rules for the SSS. This is not something to say, but I've never had a CATO, not even with old FSI F100's, which even the manufacturer--at the time, said had a 30% chance of going ka-blewy. It just keeps gettin' better. 🙂 And all you get is another engine? 🙄
I recall once upon atime when rocket costs were reimbursed. I'm a big believer in live at your own risk, but they ought a build in to the cost of each motor replacement cost FOR the rocket and motor. Hey you still eat the time and loss in building it. I buy a motor, not a lottery ticket. If one had a 30 % CATO RATE well those rocket replacements would get expensive,
J
AeroTech did come through with a motor. As some said, It would take a
while. But they did well.