Enerjet 1340/20

In my posts on this blog, I frequently alluded to how mythical Enerjet and that company's products appeared to us teenagers in mid-1970s Switzerland. At the same time, it was often difficult for us to find sufficient and reliable information about developments in our field of interest. We had to rely on issues of Model Rocketeer magazine, sporadic glimpses offered in company periodicals such as the Rocket Times or Model Rocket News. Or we deducted as much as we could from photos and text published in G. Harry Stine's Handbook Of Model Rocketry or Centuri's Model Rocket Design Manual, among others.

Congruent with our increasing skill in building and flying model rockets, we coveted any possibility to accomplish more advanced concepts and obtain motors with increased power. In the second half of the 1970s, when we became increasingly immersed in rocketry, Enerjet no longer existed, and it is very doubtful if any of Enerjet's products ever even made it to Switzerland while the company traded. We eventually found some solace when it became possible to obtain Flight Systems' products through a distributor in Germany, and we duly moved up a notch, both in motor power and materials.

But one of the rockets that always exerted an iconic radiance on me was Enerjet's 1340/20 payload rocket, first seen by us on page 231 of the fourth edition of the Handbook Of Model Rocketry, in 1976. Although I knew next to nothing about this rocket at the time, it became one of those designs that has never ceased to fascinate me in the 41 years since.

After Enerjet's demise, parent company Centuri continued to offer a number of components that were part of some of the former's most notable rockets. Among them were the #13 plastic fin unit (prod. no. F-413L), used by Enerjet's 1340 and 1340/20 designs and later part of Centuri's Phoenix Bird and Argos "Kwik Kits". Or the transition section and nose cone of the payload section of Enerjet's 1340/20, later offered in the guise of an egg capsule (prod. no. PNC-13E/ST-202), for example in Centuri's Rocket Times in fall of 1975 (a supplement to Centuri catalogue no. 761). And following the merger of Centuri and Estes, these parts occasionally reappeared as part of Estes kits, such as the Eliminator (the fin unit) or Eggspress (payload section).

Nonetheless, obtaining these parts to construct an Enerjet 1340/20 replica in the present day proved somewhat challenging, in spite of their sporadic availability and modern procurement tools such as the internet and eBay. Another surprise was the material used for the 1340/20's transition section and nose cone in their most recent guise as the egg capsule of the Eggspress. Instead of the more common, glueable high-impact styrene used for most nose cones, the plastic used for these parts is reminiscent of cheap garden toys for children, as usually imported from Asia, i.e., polyethylene. This flexible plastic is difficult to sand (and sanding is unavoidable due to the age of the original moulds), glue, and paint. I suppose this material was chosen due to its ability to absorb impacts without cracking.

The styrene plastic fin unit, on the other hand, appears to be entirely unchanged from the one I owned as part of my Centuri Phoenix Bird in 1978. The only difference is the colour in which it is moulded. As I was beginning to run low on original Enerjet waterslide decals, I had Wessex Transfers in Australia print me some replica decals.

Enerjet logo and Enerjet 1340/20 brochure sample page © by Enerjet Inc., Phoenix/AZ, USA.

Cox Model Rocket Ad, December 1972

Cox "Now: Two more ready-to-launch rockets" ad, featured in Model Rocketeer magazine, vol. XIV, no. 11, December 1972, published by the National Association Of Rocketry, McLean, Virginia, USA.

Shown are Cox' legendary X-15 plastic model rocket, recovered by parachute, and the elegant Space Shuttle America, whose booster section was recovered by parachute while the two "shuttles" glided back to the ground.

Cox ad © by Model Rocketeer, McLean, Virginia & L.M. Cox Mfg. Co., Inc., Santa Ana, California, USA, 1972.

Homage To Model Missiles, Inc.

I scratch-built this semi scale Aerojet-General Aerobee-Hi in 1986, using Centuri parts. It was an homage of sorts to the beginnings of our hobby and thus to some of the protagonists that had inspired me during my youth, ten years earlier: Orville H. Carlisle and G. Harry Stine.

As described, for example, in a fantastic article titled The First Model Rocket Kits, authored by G. Harry Stine and published on pages 5 to 9 of the February 1978 issue of Model Rocketeer magazine, Carlisle and Stine's Model Missiles, Inc. produced the Aerobee-Hi as the company's first proper model rocket kit in 1958. Moreover, I also admired the early Aerobee-Hi model rockets when I obtained what was my first copy of the Handbook Of Model Rocketry (Fourth Edition) in 1976 or 1977, such as in the formidable launch photo on page 125. We were model rocket obsessed teenagers at the time and not only glorified G. Harry Stine but also the beautifully pure design of the Aerobee-Hi rocket.

My own Aerobee-Hi was first launched on May 28, 1999, many years after I had originally completed it. The top photo shows the final preparations for this maiden flight, conducted with an Estes B6-4 motor in northeast Switzerland. As can be expected for such an immaculate design, it performed flawlessly. The lower two photos show the same rocket in May 2016, in Zurich, Switzerland.

Swiss Model Rocket Competition, 1980

Following my participation in the 6th Swiss Modellraketen-Flugtag model rocket competition in 1978, I had originally intended to partake again in September of 1979. I built a rocket designed for the altitude event, called Vehicle 2. Although I really liked that rocket, I ultimately didn't enter it, for reasons that are no longer clear to me now. The second time I thus participated in the Modellraketen-Flugtag was on the occasion of the competition's 8th edition, in September of 1980.

As usual, the competition was organized by the Technorama science museum in Winterthur, Switzerland, and held at Allmend Frauenfeld military training grounds. After having built rockets for the altitude category in 1978 and 1979, I now tried my hand at the considerably less striking egg-lofting competition. In the course of the summer of 1980, I thus built Vehicle 21 (shown above) from various CMR parts, including CMR's ENC 77 egg capsule, something of a secret weapon at the time.

All rockets of the egg-loft competition had to complete two flights using Estes C6-5 motors, both flights having to carry the same egg as high as possible and subsequently land it intact. Most rockets entered were finished rather crudely and utilized off-the-shelf Estes or Centuri parts, including heavy plastic parachutes. Astonishingly, I therefore was the only contestant with a rocket built from what for Switzerland, at that time, amounted to highly advanced competition components.

Nonetheless, this young teenager was surprised (and considerably proud, of course) when my first flight turned out to be the highest of the field. Unfortunately, the Mylar parachute was damaged upon ejection, and the rocket returned to the ground with considerable speed and only minimal braking. As it impacted, competitors and spectators alike all laughed, and I could hear how they universally predicted a smashed egg. But CMR's fantastic egg capsule had worked, and I was able to present a pristine egg to the judges and thus qualify for the second flight. It goes without saying that I suddenly received incredulous and grumpy looks from my fellow competitors.

The impact forces had been absorbed by the blown plastic of the egg capsule, however, and it had cracked along almost half of its length. Next to repairing the parachute, I thus had to perform an emergency fix with electrical tape, which made the rocket heavier and compromised its aerodynamics. Accordingly, my second flight came in some 22 meters lower than the first, which cost me what would likely have been a first place overall. Then again, I still came in second, which was fantastic at any rate, especially given the circumstances.

My participation in this contest also resulted in the very first time I ever read my name in a magazine, when the March 1981 issue of the Model Rocketeer printed a brief report titled "Eight Swiss Nationals".

As was the case when I first participated in 1978, there were again people who blatantly disregarded the contest rules; in this case the rule that the person entering the rocket also had to be the one who actually built it. There was at least one entrant I personally knew who had zero model rocket experience and yet entered a rocket built by a third party with considerable expertise. When the person in question won the altitude competition in this manner, I felt truly disappointed. I didn't bother to report it this time around, but I decided to refrain from ever participating again. I would be perfectly happy just flying rockets with my friends.

Flight Systems Motors

A selection of 1970s vintage Flight Systems Inc. black powder motors. The discovery of Flight Systems' more powerful motor range in the late 1970s enabled us, finally, to fulfil a burning desire to construct rockets capable of a noticeably superior performance.

As young teenagers in 1975 and 1976, we initially built self-made and utterly flawed aluminium tube rockets filled with any highly flammable material we could obtain. These efforts resulted in far more explosions than legitimate flights, and it is solely due to sheer luck that we came out of this period without any serious injuries. In late summer of 1976, we finally discovered professional 18 mm and 24 mm black powder motors of the A through D range, first those manufactured by Estes, and soon after those by Centuri. At this time, they were still somewhat difficult to acquire in Switzerland. Frequently driven by ambition and youthful enthusiasm, however, we were often dissatisfied by the speeds and altitudes attainable with these motors.

Through our subsequent NAR membership and the associated subscription to the Model Rocketeer magazine, we soon learned that there existed further companies that manufactured different motors. But it was only when German distributor ESE Electronics and Scientific Equipment started carrying the Flight Systems Inc. product line that we finally were able to actually purchase that company's E and F motors. They were a revelation to us at the time, and they enabled us to accomplish a brief revolution in our rocketry activities before certain harsh realities in our lives temporarily forced us to divert our attention to other issues.

Shown in the image above are Flight Systems Inc. 21 mm E5-6 motors produced in May 1978 (top left, yellow header), 21 mm D20-7 motors produced in June 1979 (top right, blue header), a 27 mm F7-4 motor produced in June 1979 (second from bottom, green print) and a 27 mm F100-8 motor produced in July 1979 (bottom, purple print). The small plastic bag at bottom right holds the electric ignitors. The photo was taken in Zurich, Switzerland, on May 18, 2016.