Estes Engine Question...

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Well-Known Member
Jan 18, 2009
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Question guys...I was cleaning out my engine magazine today, and found two older "D' motors...
I don't know how long I've had them and don't remember when I might have gotten them...anyway they're "D 11 9"s and they don't show up up on any new motor lists...
For the life of me I 'm not sure what you would do with a 9 second delay...LOL
It's a blue label marked for single or upper stage use...and it's marked as a SLD "D" ENGINE.
Anyone have any info on this motor??? 9 seconds??? WOW!!!
Sounds like a collector's item to me. You're right, what can we build that needs the 7's, never mind the 9's? I'd just keep them for the collector value.

Len Bryan
Nah, build a sleek minimum diameter rocket and fire that puppy up with a streamer for recovery. Upscale a Ninja or a Wizard and let 'er rip.
You will notice that the D11-9 has less fuel (lower total impulse) than the D12, to make room for the longer delay. The motor was ment for high performance rockets (especially multistagers)

I think I heard something about the D11-9 having reliability problems? Maybe somebody who has been in this hobby longer than I can answer that question... becasue they were long gone when I entered the picture.
The D11-9 was intended for two stagers such as the Sea Strike-D. It was also on the motor list of smaller single stage rockets such as the Cherokee-D, but my Cherokee flew perfectly on D12-7's. I never used the D11-9 in anything other than a few two stagers.

The original Estes D motors, the D13's, were definately prone to CATO. I don't remember the D11-9 giving trouble, but maybe I've just been lucky. I've only had a handful of motor failures in 30 years. All of my D11-9's worked. They were probably just dropped from the line because very few people needed that long of a delay and they didn't sell well enough to keep making them.


I still have not decided what to do....
I have had a couple of offers from TRF members that want to purchase them....that's cool...but...
I've started thinking about that post with (mention of) the "CHEROKEE D"....just the excuse to buy that clone I've been looking at...(did I mention I loved that rocket...had several of them years ago...!!!).
Please don't misunderstand me now....I'm not looking to raise the stakes or anything...I've grown sentimental over them.. sorta...LOL
Oh Well...I'll keep thinking...

P.S. I'm really not this "wishy-washy" wife says it the medication....LOL
Build the Cherokee-D, you won't regret it. Great rocket.
My Estes D-motor experience and opinion pretty much matches tbzep's. I flew quite a few D13s and never really had a problem with them---unless they were 'helped' behind my back by one of the other guys adjusting the motor with a hammer.

D11 motors worked just fine in my experience. I don't remember a single problem with any that I used personally or saw someone else use.

D12s have continued to work OK too, and will give you great flights on your Cherokee the third time around . . .

One not-so-small consideration to include in your thoughts when trying to figure out whether to sell these two old D11s:
Get ALL your ducks in a row with the USPS, get all the prior approvals for shipping BP through the mail, get all packages properly and fully marked. (Especially since 9-11 and the new HSA rules) We don't want to see you spend your last years in Leavenworth.