Friday, March 27, 2020

Estes Trident - First Baffled Ejection?


TRIVIA: The original (three side tubed) Estes Trident was probably the first model rocket that didn't require recovery wadding. The ejection gases were directed out into the three outside BT-5 tubes then back into the upper, central tube to eject the parachute. The Trident instructions say to use wadding -  I bet Estes never tried a Trident test launch without using it.
Remember cutting those narrow slots in the BT-5 tubes with a dull X-Acto blade? Ejection baffles have evolved since and are much simpler now.
The Semroc instructions say: "Apply a few sheets of recovery wadding in the top of the main body tube. Since the pods provide for an ejection baffled, recovery wadding may not be absolutely necessary". I doubt the recent Estes Explorer (based on the Trident design) would need it either - but you didn't hear that from me.

The original Estes Trident (with three ducted side tubes) was available from 1967 - 1974.
A revision called the Trident II (two ducted tubes) was sold from 1990 - 1991.
How can you still call it a TRI-dent with only two tubes?

To see the original Trident instructions, go to Jim Zs: CLICK HERE

5 comments:

  1. Yeah, I thought that Trident II business was silly.

    Semroc produces a Trident reproduction in which the gas passages are laser cut for you and there is also a jig to help assemble it in the kit.

    This was one that I dreamed about as a kid, but couldn't afford....and of course I have purchased two and built one of the Semroc versions at over 10x the original price.

    I put one square of wadding in the bottom of the upper tube when I fly mine, but it doesn't appear to be really necessary.

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  2. I have an original Trident, built, and never flown! I took it to a launch last year, and realized I had removed the rotted shock cord probably a few years earlier, but not replaced it! D’oh!
    The Trident IIs were pathetic.And, the graceful curves of the original Trident’s fins were ditched. I turned one into a futuristic fighter, kind of a Trident-Interceptor mash-up. Another got opened for scrounging parts.

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    1. Lee, if you ever fly it, watch out for strong ejection charges! I built a Trident from the xKit (before Carl released the repro with all the laser cutting) and an ejection charge blew the lower motor compartment apart, though I didn't know it until I recovered the model.

      The laser-cut passages are rather larger than the hand-cut ones I did for the xKit build...so less backpressure in the system. I've not had any issues with the later one in ~15 flights or so.

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    2. Bernard, thanks. I’ve always wondered how it would handle ejection. I would consider my 18/20 RMS with a smaller amount of BP, but I sure don’t want to fly it on a D!
      It may be time to get a tiny timer for ejection, and use a plugged booster, but I’m assuming I cannot do that at an NAR-sanctioned launch?

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    3. Plugging boosters is kind of a grey area as I understand it.

      I'd guess my Semroc repro Trident may get to 400-500 feet or so on a C6 (I haven't put a Q-Jet C12 in it yet—nor an altimeter oddly enough) so depending on where you fly a D13 in the 18/20 case might be OK.

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