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Old 06-12-2018, 03:46 PM
BARGeezer BARGeezer is offline
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Quote:
Originally Posted by blackshire
Not directly, but going by its 26.3" overall length (see: http://www.ninfinger.org/rockets/ca...-2/782cen6.html ), and the 28.0" long Enerjet 1340 Sounding Rocket's component dimensions (given on page 2 here: http://www.oldrocketplans.com/enerj...340/enj1340.pdf [its main body tube was 13" long, and its payload tube was 8" long]), it should be possible to derive them. One difference between the two was that the 1340 Sounding Rocket used quite large, high-impulse Enerjet motors, and the length of the protruding rear portion of the motor counted as part of the 28.0" length. What was the typical "protrusion length" for these motors? (For 13 mm motors, it's 1/4", and for 18 mm motors, it's 1/2".) *ALSO*:

This picture of the "bulbous payload section" 1340/20 (see: http://www.oldrocketplans.com/enerj.../enj1340-20.pdf [its main body tube--to the rear edge of the fin unit, the drawing seems to show--was 12.0" long]) shows the protruding motor pretty well; it looks like it's protruding 1" or so behind the rear edge of the fin unit (there's also a short length of motor tube, or body tube, just behind the rear edge of the fin unit). Here (see: http://www.ninfinger.org/rockets/ca.../72ejetcat.html ) is the 1972 Enerjet catalog, which shows the big motors the 1340 Sounding Rockets used.


By process of elimination, the length that the motor tube protrudes is .6" ( Overall length minus nose cone length, minus payload tube and main body tube with fin can length, minus coupler length). I have doubts that an Estes E2X rocket can handle a 24 or 29mm composite propellant motor, however.
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