CTI J530 Cato

First, this isn't to bash CTI! I have and will continue to fly a bunch of CTI - 24 thru 54mm.

Last weekend at Battle Park I flew my 4" scratch built L2 cert rocket on a 38mm 6XL J 530. This was the third flight of this rocket on a 38mm CTI - first was a J270, then a J 354.
Everything was normal going together, no issues getting it into the case and the closure threaded right in (didn't try to cross thread like they sometimes do). The rear closure let go a few hundred feet in the air.

Here is a .pdf with a bunch of pictures and some summary of the flight.
https://drive.google.com/file/d/0B2rfKF8ZbtXNM1R1T3lBUWViOE0/edit?usp=sharing

And a not very good video: https://www.youtube.com/watch?v=SltYYXfSm4A

I'm not sure what happened - my best guess would be that a pice of the liner/casting tube clogged the nozzle.

I have forwarded this info on to the vendors and hopefully they will pass it along to CTI. And we'll see where it goes from there, I was really looking forward to flying this load! Maybe next season. It sure moved the relatively heavy rocket off the pad in a hurry!

Sorry to hear of this. That well and truly sucks.

Odd that the delay was undamaged and the last grain unburnt. Could it be the ignitor was not fully inserted or slipped out of position prior to ignition? I ask because I'm pretty sure this motor has a BP pellet at top. If ignition occurred at the pellet, one would expect these to have signs of burning. Perhaps ignition occurred at grain #5 or #6, rather than at grain #6XL?


Regardless, I am sorry to hear of the damage. Hope you figured out what happened, and never have a problem like this again moving forward...



Later!

--Coop

I would like to see CTI redesign the 38mm cases. A 54,29,24 closure would be nice. I know it means buying some new cases but with the spacer system used now days we would not have to buy many new cases. You would like a new closure would save CTI money.

Coop, the delay and the last grain both burnt some - but when the case depressurized they went out. There is about 1/16" missing from the delay and while I'm not sure what the starting core size was my eyeball tells me that at least 1/2 of the propellent is gone from the grain.

I don't like the plastic closure either. It seems like they could design a metal closure to fit the current cases so you don't have to buy new cases, and then just re-disgn the nozzle. The rest of the load could stay the same. But maybe this would require then to re-cert all of their 38mm loads, which is a lot!

rocketkid88 said:

It seems like they could design a metal closure to fit the current cases so you don't have to buy new cases, and then just re-disgn the nozzle. The rest of the load could stay the same. But maybe this would require then to re-cert all of their 38mm loads, which is a lot!

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I have talked to CTI about this. Re-certificating every motor in every case would be required. Pretty sure that is the reason we wont soon see a change. I have had pretty good luck with the current design but, I would love to see a few more looooong burns. The plastic closure really limits that.

Do you still have the cardboard tube it came in? This is the exact failure I had about a year ago. My vendor said it was the fourth or fifth one he had seen let go from a certain batch. 10/12 38mm Imax if I remember right?

The onsite vendor was nice and gave me the option to replace the reload with cash or a new reload. I took the cash, but I'm not sure if I would trust that case again if I chose the reload.

It sucks. Sorry man.

bandman444 said:

Do you still have the cardboard tube it came in? This is the exact failure I had about a year ago. My vendor said it was the fourth or fifth one he had seen let go from a certain batch. 10/12 38mm Imax if I remember right?

The onsite vendor was nice and gave me the option to replace the reload with cash or a new reload. I took the cash, but I'm not sure if I would trust that case again if I chose the reload.

It sucks. Sorry man.

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I had a 6Xl Imax fail too, from what I am assuming is the same batch. it was a while ago.

CTI gave me a new load and a new case no real questions asked.

catos happen nothing is going to change that.. but good customer service... that makes it all happen!

sorry about your loss but CTI will take care of you!

The date was Dec 2011 - so it was an old-ish motor. I didn't even look at the date till after the flight since I bought it the same day, I guess Kevin doesn't sell many 6XL IMax motors!

Is the J530 still being produced? I don't see it on the Wildman site.

rocketkid88 said:

The date was Dec 2011 - so it was an old-ish motor. I didn't even look at the date till after the flight since I bought it the same day, I guess Kevin doesn't sell many 6XL IMax motors!

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That is fairly old and it may be a bad batch...I remember hearing about some 6G XL issues a little while back. Jerry O had a few XL blues CATO in his Iris a few years back IIRC...maybe it's related.

Coop said:

I ask because I'm pretty sure this motor has a BP pellet at top.

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The J530 doesn't have a pellet, it comes with a special dipped e-match.

mikec said:

The J530 doesn't have a pellet, it comes with a special dipped e-match.

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Oh, does it? Okay. I knew a few didn't, but thought this one did. I stand corrected. Thanks!


Later!

--Coop