Reliability Estes E9 vs E12

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J Blatz

Well-Known Member
TRF Supporter
May 8, 2010
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Isn't one or the other of these CATO prone?

I am fixing to stock up on BP motors and would like to get a couple packs of whichever is better.
I haven't used an E12, but I did have an E9-4 CATO on a brand new Big Daddy. Estes replaced the kit and the motors. I've used the replacement motors without incident.
From other discussions here on TRF, I'd say it has more to do with lot # than 9v12. There are lots where both thrust levels have CATOed.
I think that may be the case. As best I can figure from my logs, the E9 was out about 10 years before the E12 and, until the E12 issues started cropping up, I don't remember widespread problems with the E9s. This is just what my flawed memory came up with.
I had an E-9 cato fairly spectacularly this last weekend. Blew both ends out about 10 to 20 feet off the ground. Loud boom and lots of sparks. In a saucer so no damage. I have had enough of them blow that I only use them in saucers.