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  1. #1
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    R134: NAR S&T NEW MOTOR CERTIFICATION

    The following motor has been certified by NAR Standards & Testing for
    general use as a Model Rocket Motors effective December 14, 2009


    *************************************
    Quest:

    A3-2,4
    13mm x 55mm
    1.71 Newton-seconds Total Impulse
    2.79 Newtons Peak Thrust
    0.82 Newtons Average Thrust

    Propellant mass: 3.6 grams

    *************************************

    Attached Files Attached Files

  2. #2
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    Oh, my, oh my..............

    A shorty mini!

    Mark K.

    Last edited by MarkII; 24th March 2010 at 04:21 AM.
    Mark S. Kulka NAR 86134 L1, ASTRE 471, Adirondack Mtns., NY
    Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity
    In the forest no one can hear you order a grande caffè misto.
    Warning: I brake for invisible squirrels

  3. #3
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    Cool!

    I look forward to flying these motors.

    So many new products by many different manufacturers.

    It's a great time to be involved with hobby rocketry!
    Bob

  4. #4
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    Interesting..... very interesting.

    *strokes non-existent goatee*

    I like this. An A-class mini motor with two different delays. Not seen since the Estes A3 shed its -2 and -6 delays.

    NAR 88789 L1 8/14/2009

    No more running. I aim to misbehave.

  5. #5
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    Quote Originally Posted by MarkII View Post
    Oh, my, oh my..............

    A shorty mini!

    Mark K.
    uh, no, that's actually longer than the Estes mini, slightly shorter than the old MRC MiniJets.

    Also note that it has HALF the liftoff thrust of an Estes A3, and less than half of the average thrust. Twenty percent less total impulse using five percent more propellant!

    According to the data it burns for over two seconds.

    It'll be neat for VERY light models, and might be a boon for competition.
    Roy Green
    nar12605 L2
    Southern Area Rocketry

  6. #6
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    I have mixed feelings on this one. As has been said already, the specific impulse of this A"3" is vastly inferior to the Estes A3. That being said however, this isn't really an A3. It is an A1. I like the long burn aspect, but forgive me for saying so, this kind of false advertising has lead to the crashes of some models with the Quest C"6" (Really a C3.5). Why the NAR allows the mislabeling is beyond me. Don't get me wrong, for something like an M motor labeled as a (hypothetical) M2000, a two or three Newton difference is inconsequential (or even a 20 or 30 Newton variation). However, at this scale, that is a 66% deviation!
    Last edited by TheAviator; 24th March 2010 at 06:21 AM.
    Brian J. Guzek
    NAR#86418, L1
    Clubs: Pittsburgh Space Command, Mantua Township Missile Association

    Competition Rocketry: Because three fins and a nosecone just doesn't cut it sometimes.

  7. #7
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    Quote Originally Posted by TheAviator View Post
    I have mixed feelings on this one. As has been said already, the specific impulse of this A"3" is vastly inferior to the Estes A3. That being said however, this isn't really an A3. It is an A1. I like the long burn aspect, but forgive me for saying so, this kind of false advertising has lead to the crashes of some models with the Quest C"6" (Really a C3.5). Why the NAR allows the mislabeling is beyond me. Don't get me wrong, for something like an M motor labeled as a (hypothetical) M2000, a two or three Newton difference is inconsequential (or even a 20 or 30 Newton variation). However, at this scale, that is a 66% deviation!
    Brian, it infuriated me for a long time as well, until I had an epiphany and realized that, long ago, the Engine Code became a Product Name and therefore a marketing tool.

    Say, for instance, that you were a model rocket motor manufacturer, and you had a C7-5 motor. It produced 10NS total impulse, and had seven newtons average thrust. Your intent was to sell that motor through Hobbytown, Michaels, and Hobby Lobby. You may or may not have kits to sell, but even if you did, the majority of kits in the store would be Estes kits. A large number of Estes kits have as one of their recommended motors a "C6-5".

    It is bad enough that your motors have to compete with similar motors that have an Estes logo, but when Timmy or Timmy's parents look for motors to use with Timmy's new rocket, or worse -- the buyers for the stores look for motors to stock, they more than likely won't take a chance on your "C7-5" motors, or Jack's company's "C4-4" motors, which would probably work just as well.

    Instead, you and Jack both label your motors "C6-5", and get them certified as such, since there's enough leeway in the NFPA tolerances. Now, all you and Jack have to compete against is the Estes logo.

    In the same way, Estes itself can't do much about it. Say that, over the years, the quality of ingredients for their black powder, particularly the charcoal, has changed. They can't make a C6-5 motor quite like the C6-5 motor they made 20 years ago. To get the total impulse back into the correct range, they have to cut the average thrust back to 4.5 newtons. And they have to cut back a tiny bit on the delay powder so they have enough room in the casing for the slower propellant. This causes the 5 second delay to become more like 3.7 seconds.

    They can't suddenly start selling a "C4-4" motor, since all their back catalog of models specifically recommend C6-5! And they can't call it a "C5-4" for the same reason and because a few might confuse it with the old "Super C5" motor from 30 years ago. But as long as the triennial certification from the NAR is done and is within those somewhat loose NFPA tolerances, they can still call it a C6-5 and all is well.


    Of course, in this case the Quest A3 motor itself is too big to fit in an Estes model anyway (55mm vs Estes' 45mm) so the branding issue may not be important here, but this explains why there can be such widely differing motors on the low end all with the same branding.
    Roy Green
    nar12605 L2
    Southern Area Rocketry

  8. #8
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    Quote Originally Posted by TheAviator View Post
    Why the NAR allows the mislabeling is beyond me.
    Before you blame the NAR for this labeling, you might want to read the NFPA code (1125) that discusses average thrust labeling requirements.
    A dark night in a city that knows how to keep its secrets. But high above the quiet streets on the twelfth floor of the Acme Building, one man is still trying to find the answers to life's persistent questions. Guy Noir, Private Eye.

  9. #9
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    Quote Originally Posted by TheAviator View Post
    Why the NAR allows the mislabeling is beyond me.
    I'll save you the time looking it up. We have absolutely no choice but to accept the manufacturer's labeling. The wording in NFPA 1125 was intentionally screwed up years ago because the traditional labeling of popular motors was wrong (inaccurate test data from the early days and motor redesigns are the reasons I've heard) and it was felt that changing the name of the motor would confuse people who know they're rocket flies safely on an A8-3 or B6-4 but really don't know what those numbers mean. The current wording in 1125 says the average thrust equals the average thrust. It's a circular argument allowing the manufacturers to put anything they want on the label. Assuming it's approved, the new wording of 1125 says it has to be within 20%.

    Someone caught it before I posted it here but the average thrust was listed as 3.82 which was pointed out to me is really hard to do with a peak of 2.79. I didn't catch the typo because I read the 3.82 and was thinking that for once a motor actually had an average thrust close to the label. That should have been my first clue that I needed to double check the numbers.

  10. #10
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  11. #11
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    Quote Originally Posted by GuyNoir View Post
    Before you blame the NAR for this labeling, you might want to read the NFPA code (1125) that discusses average thrust labeling requirements.
    Quote Originally Posted by billspad View Post
    I'll save you the time looking it up. We have absolutely no choice but to accept the manufacturer's labeling.
    Quote Originally Posted by RoyAtl View Post
    Brian, it infuriated me for a long time as well, until I had an epiphany and realized that, long ago, the Engine Code became a Product Name and therefore a marketing tool.
    Thanks for the clarification. Sometimes I need to remind myself that the NAR, TRA, and CAR aren't the only ones out there pulling strings.

    In any case, I am definitely looking forward to this for some RGs. It may have a higher propellant weight, but it looks like the empty casing is only marginally heavier than the Estes A3.
    Brian J. Guzek
    NAR#86418, L1
    Clubs: Pittsburgh Space Command, Mantua Township Missile Association

    Competition Rocketry: Because three fins and a nosecone just doesn't cut it sometimes.

  12. #12
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    Other applications

    Quote Originally Posted by shreadvector View Post
    Very long burn time. Perfect for competition boost gliders.
    Or, if the total impulse stays within limits, this could be a great upper stage sustainer for two-stage versions of competition rockets (altitude, PD, SD)

    Or, for all those paper and cardstock model rockets out there that would shread under normal A-B-C power, here is a motor design that will get them to decent altitudes.

    Could be a great motor for competition in a lot of A impulse classes? (not just BG)
    An apple a day will keep almost everyone away....if you throw hard enough.

  13. #13
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    Quote Originally Posted by RoyAtl View Post
    uh, no, that's actually longer than the Estes mini, slightly shorter than the old MRC MiniJets.
    D'oh! Right!

    Never saw the MRC MiniJets. When were they made?

    Mark K.
    Mark S. Kulka NAR 86134 L1, ASTRE 471, Adirondack Mtns., NY
    Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity
    In the forest no one can hear you order a grande caffè misto.
    Warning: I brake for invisible squirrels

  14. #14
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    Interesting..... I'm in the process of scratch-building several models for 13mm motors for schoolyard flying....I'll have to try to make allowances for this longer motor at least in the lighter ones. I can see where these might be great sustainers for some kinds of competition.

    Heck, what about some kind of parallel-staged model ala the just-released Delta IV Heavy, but of course rather smaller, with Estes 1/2A3-2Ts or A10-3Ts in the "strap ons" (or even MMX-IIs) and one of these in the sustainer. Sometimes I think too much....
    Last edited by BEC; 25th March 2010 at 06:22 AM.
    Bernard Cawley
    NAR 89040 L1
    AMA 42160
    KG7AIE

  15. #15
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    Quote Originally Posted by MarkII View Post
    D'oh! Right!

    Never saw the MRC MiniJets. When were they made?

    Mark K.
    1971. And I made a cardinal mistake. MPC (Model Products Corporation) not MRC (Model Rectifier Corporation). First public flights at the 71 MIT convention in April. First mention of them was in their full page ad in the June 1971 Model Rocketry Magazine, and Harry Stine's article about them the next issue. That prompted Estes into making the Mini-Brutes (Estes' original marketing tag for the dash-T motors and their rocket kits). As I recall, Estes responded to the Minijets fairly quickly (less than four months). I know we got a pack of each in the contestants' packet at NARAM-13.

    The original Carlisle motors were roughly this size, and there was a manufacturer around 1965 ("Unijet"?) that also made motors this size.

    Roy Green
    nar12605 L2
    Southern Area Rocketry

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