O3400 reliability experience

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Nick@JET

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Looking for people that have flown the O3400. Thinking of flying one in a 83lb rocket (total loaded weight motor included). After looking on YouTube i noted 3 or 4 catos and also several successful flights.

Sims at 840mph - and approx 12K' I'd like to push the rocket - I think it will take it without issue so What has your experience with reliability been?

Has there been info on what caused those CATOS? Assembly error, component error etc?
 
I built 3 of them, for other fliers.

All 3 flew successfully.
I also witnessed the one that set the new record in Australia, Nic built & flew that one, during Thunda-Down-Under.

Argonia...Airfest.. I built another one for a flier. Again perfect flight.

Strict adherence to the build instructions are a MUST! Grains all glued up day before flight...spacer O rings used...
None at top grain to top plate.

Be sure all grains have nice fit....before attempting glue-in. Your in trouble if ya slather glue on one, and it won't go down liner!

I built 4, but did not fly them myself. All were great flights. I have not seen any wonky flights out of 7 witnessed.
 
I built 3 of them, for other fliers.

All 3 flew successfully.
I also witnessed the one that set the new record in Australia, Nic built & flew that one, during Thunda-Down-Under.

Argonia...Airfest.. I built another one for a flier. Again perfect flight.

Strict adherence to the build instructions are a MUST! Grains all glued up day before flight...spacer O rings used...
None at top grain to top plate.

Be sure all grains have nice fit....before attempting glue-in. Your in trouble if ya slather glue on one, and it won't go down liner!

I built 4, but did not fly them myself. All were great flights. I have not seen any wonky flights out of 7 witnessed.


I have flown 2 O3400 both at Argonia. Great Motor. Crazy Jim helped me put one of mine together a few years back. But I guess just like any other motor there could always be that chance of a cato
 
Some have been flown down here in Australia and AFAIK there were no CATOs.

I have one sitting in the motor store currently :)

If you email "info (at) ausrocketry (dot) com" and ask the question you should get the definitive answer for our bailiwick.
 
Looking for people that have flown the O3400. Thinking of flying one in a 83lb rocket (total loaded weight motor included). After looking on YouTube i noted 3 or 4 catos and also several successful flights.

Sims at 840mph - and approx 12K' I'd like to push the rocket - I think it will take it without issue so What has your experience with reliability been?

Has there been info on what caused those CATOS? Assembly error, component error etc?

Is this for the QCC Explorer? Perhaps at Airfest maybe?
 
Is this for the QCC Explorer? Perhaps at Airfest maybe?

Yes - AF is a go for me with work so 90% I'll be there with the QCC and likely my first O - just hoping my faux intakes stay on. Might have some aero plugs made for the intakes. I already have an M1939, but may save that for MWP. The M1939 went 7K at 450mph and the rocket could have easily taken more off the pad. So hmm just the intakes - everything else will take it, Fins are strong, have thrust plate and FWNC - this would be first Mach and it's my L3 rocket so want to keep it :).
Gus has the motor which I may purchase for AF.

Thank you all for the replies and the confidence in the motor - so now to save up some funds for that motor.
 
Really thought that was a busted pipe elbow at first glance. What in the world happened?

I'd say the micro entabulator over compensated from the excess of turbo hydro fusion and the clockwise rotation of the muffler bearing tore through the outer case of the blinker fluid retainer...

Nailed it! :wink:
 
I'd say the micro entabulator over compensated from the excess of turbo hydro fusion and the clockwise rotation of the muffler bearing tore through the outer case of the blinker fluid retainer...

Nailed it! :wink:

You're reminding me of Brian Regan's monster truck driver.
 
That is (was) a Tru core 2 grain 38mm case. It had a research green motor in it that sorta didn't work right. One guy at the launch told me he's been flying rockets for 30 years and never heard a bang that loud. The thrust ring, snap rings, forward closure, nozzle, and nozzle washer were never found. It shredded my rocket and bent the 1010 rail. I figured out what went wrong- it's the only CATO I've had on my research motors.
 
I'd say the micro entabulator over compensated from the excess of turbo hydro fusion and the clockwise rotation of the muffler bearing tore through the outer case of the blinker fluid retainer...

Nailed it! :wink:

Any fool can see it was COUNTERclockwise rotation of the muffler bearing! If it had been clockwise, you would have seen right-hand-rule von Mises brittle fractures. Here you have obvious 45-degree hoop stress ductile tearing with some block shear inclusions. :p

Looks like it was an exciting moment on the launch pad!
 
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