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Jetex (Jet-X) and/or Rapier motors NAR Certified?
Hello All,
I know that Centuri sold Jetex motors many years ago (see: http://www.ninfinger.org/rockets/ca...64/64cen40.html ), and they were apparently NAR Certified as "1/2A" and "A" motors. Were/are the new Jet-X motors (see: http://jetex.org/links.html ) and Rapier motors (see: http://www.shortysbasement.com/inde...viewCat&catId=5 ) NAR Certified? (The Rapier [see: www.rapier.cz ] is a Czech-made single-use, slow-burning rocket motor that is used mostly for F/F [Free Flight] model aircraft. It can be ignited using a supplied wick, DT fuse (De-Thermalizer fuse), or a special hand-held reusable "hot-wire" electrical ignition "stylus" that is made for this purpose. Most of the Rapier web site text is in Czech, but you can translate all of it by typing "www.rapier.cz" in www.google.com and then clicking on the "Translate This Page" option.) The Jetex (Jet-X) and Rapier motors could provide additional performance and/or scale realism flight options for boost-gliders and rocket gliders, especially R/C (Radio Controlled) ones that could employ inflight Jet-X or Rapier motor ignition on command.
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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#2
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The answer is - NO. For a complete list of NAR certified motors, please visit: http://www.nar.org/SandT/NARenglist.shtml Bob |
#3
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That's a pity--they would make for enthralling flights at contests and demos. Still, there's nothing stopping us (particularly those of us who live in isolated areas) from using them on boost-gliders and rocket gliders.
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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR |
#4
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Then they are no longer model rocket boosted gliders, but Jet-X/Rapier propelled gliders Bob |
#5
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..and rocket propelled aircraft are specifically exempted from NFPA 1122 also.
terry dean
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"Old Rocketeer's don't die; they just go OOP".....unless you 3D print them. |
#6
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To me they sound like an interesting hybrid..............conventional model rocket boost with a Jetex sustainer at altitude. The Jetex motor would have to be slung at the CG (with the rocket motor ejected) and could give really interesting performance. Not a true glider for sure, but a new avenue that many model rocket enthusiasts might find both challenging and rewarding. Blackshire, if you continue down this path I would love to hear about your flights. Joe |
#7
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I remember reading another discussion about this somewhere awhile back, perhaps in the oldrockets group, but I'm not sure. My leaky and fungible memory of it is that it was started by someone asking if HLG's that were augmented by Jetex or Rapier engines could be considered to be model rockets, and if they weren't, then why not. I think that it ultimately came down to the idea that when you are talking about the Jetex/Rapier/HLG thing, you are talking about a different hobby. A perfectly fine hobby, and one that certainly has some cross-over appeal to us glider fans in model rocketry, but still, a different hobby, and not model rocketry. This was not meant to be exclusionary or dismissive; the point was that model rocketry is a certain kind of discipline, and is not all things to all people. There are other aeronautically-oriented or flying hobbies that may use rocket or jet propulsion in some form, but that fact alone does not inherently make them part of model rocketry.
The key thing that distinguishes our hobby from those others is our adherence to the Model Rocketry Safety Code; it is our foundation document, the source from which our entire hobby is derived. One of the tenets of that code has to do with our pledge to only launch our models in trajectories that do not deviate more than 30 degress from vertical. As I understand them, Rapier engines, and their Jetex predecessors, are long-burning but very low thrust engines that are incapable of lifting the models that use them straight up from a standing start entirely on their own, without at least some other method of boosting them. Rapier and Jetex engines are considered to be jet propulsion devices, but they are not rocket engines. (In fact, the inventors and founders of Jetex themselves insisted on this distinction.) I don't know if anyone has ever submitted either brand to NAR S&T for certification, but since they are not used to propel model rockets, I am not sure that S&T would even consider testing them. None of this is meant in any way to disparage or disapprove of their use in FF gliders. In fact, this sounds like a fascinating extension of that hobby. The only point is that they are used in a different hobby. The particular characteristics of Jetex/Rapier engines make them unsuitable for launching model rockets, including model rocket-boosted gliders. If I have any of this wrong, I am sure that someone will jump in to correct me. MarkII
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Mark S. Kulka NAR #86134 L1,_ASTRE #471_Adirondack Mountains, NY
Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity
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#8
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Thank you. It may be a while before the model(s) is/are built, but I've been thinking in terms of F/F (Future/Fiction Scale) models of some of the earlier Phase A and Phase B two-stage, fully-reusable Space Shuttle designs (see: http://www.astronautix.com/lvs/shuttle.htm ). The orbiter would use a Jet-X or Rapier motor, which would provide nice horizontal or gently climbing flights after the orbiter separates from the glide-recovery winged booster at altitude. The Jet-X or Rapier motor's wick could be ignited either at launch (electrically) or by arranging for the ejection charge(s) of the booster's model rocket motor(s) to ignite it. In the latter case, the set-up would be similar to the staging arrangement of the 10.5 mm Apogee Components motors. (Due to the 10.5 mm motors' very small nozzles, the upper stage motors were ignited with a staging wick which was lit by the booster motor's burn-through.)
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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see: http://www.lulu.com/content/paperba...an-form/8075185 http://www.lulu.com/product/cd/what...of-2%29/6122050 http://www.lulu.com/product/cd/what...of-2%29/6126511 All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com. NAR #54895 SR Last edited by blackshire : 03-17-2009 at 09:26 PM. Reason: I had to re-do the links. |
#9
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For anyopne interested in seeing the Rapiers, here's a pic.... I think I bought them from J.Windsor (sp?) They are 12 mm diameter, 50 mm length with a 18 second burn time, 2.0 ns total impulse. No ejection charge or delay. |
#10
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I didn't realize that this was what you were talking about doing when I wrote my previous post. It's an interesting idea. MarkII
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Mark S. Kulka NAR #86134 L1,_ASTRE #471_Adirondack Mountains, NY
Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity
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