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Old 08-14-2015, 09:29 AM
Jerry Irvine's Avatar
Jerry Irvine Jerry Irvine is offline
Freeform rocketry advocate.
 
Join Date: Jan 2008
Location: Claremont, CA "The intellectual capitol of the world."-WSJ
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Default Enerjet 2250

Now I have a treat for YORF. Actual photos of an Enerjet 2250 in flight with 3 FSI F100-10. Circa 1970.

Jerry Irvine brings an Enerjet 2250 rocket (Larry Brown, Lee Piester) to the pad at the Claremont Rocket Society Lucerne launch. It is powered by three Flight Systems Incorporated (Larry and Lonnie Reese) 28mm paper case, black powder propellant core-burning F100-10 motors ignited by three FSI electric matches. The rocket has three thick wall 29mm tubes projecting out of the rear of the 2.25" ID 2.34" OD main tube which has a payload tube (black and silver) and a balsa nose cone. The rocket uses wedge attach balsa fins. It was flown from a 3/8" rod as a 1/2" rod would be too tight for the supplied BT-5 handlebar (long) launch lug. Pretty sure that is a Plymouth Duster and a Rocket Car in the background.

The Enerjet 2250 is on the pad which is a launch rod stuck into the dirt, with no blast deflector to promote dust on ignition for a better photo. The intrepid recovery crew is in the background. Recovery is by 24" silk parachute (not friggin' nylon). It takes a while to single deploy recover from a full delay coast flight of 3 F100-10 motors, but by flying in the morning when the wind is calm it lands nearby.

Liftoff! Jerry Irvine's Enerjet 2250 lifts off with three F100-10 power and flies straight and true. The rocket was flown in this configuration over a dozen times in its lifetime. Including once at Cahuilla Park in Claremont, the highest power flight ever in Claremont, then or since. That flight was used as a test case for a three station optical tracking system. The data from that test has since been lost to time.

The Enerjet 2250 is unique in that the three 1.14" ID tubes do not slide fit into the 2.25" ID main tube. The ends of the motor tubes must be crushed to slide into the rear of the main tube which substantially reduces the frontal area for a 3 cluster 29mm rocket. This process is not well documented in the kit so several suggestions were accepted then I proceeded with the one time step of inserting the tubes. It worked!

One of the two Centuri Sky Track trackers is shown in this image of the CRS Claremont launch control area set-up. The utility box contained the motors, wadding, and smaller replacement electronics like clips. The three station tracking system added a custom tracker using an MIT plan, possibly the one by Trip Barber? We used those Sky Tracks at every sanctioned contest, records trials and even Lucerne R&D launches right through 1992 when they were "retained" by Charles E. Rogers, then subsequently "stolen" by "unknown persons" from their Lucerne Test Range set spots during a post-Jerry TRA launch. Oops. Last known photo.

Historical Jerry
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