Monday 31 August 2020

United Press International Photo 1969, Part 2


A further United Press International photo from a series of images taken at an NAR launch at Goddard Space Flight Center in Greenbelt, Maryland, on November 29, 1969. The sophisticated rack launch pad shown in this beautifully detailed photo is mainly dominated by launch-ready old-school boost gliders typical for the period.

The second rocket from the left looks like an extended Estes Astron Drifter, the third model from the left appears to be an Estes Astron Falcon rocket glider.

The press text attached to the rear of the original photo reads as follows:

WAP 1613622

MODEL ROCKETRY

GREENBELT, MD: On the launching pad at the Goddard Space Flight Center here, five await their turn while a sixth model rocket is launched. Model rockets do not require concrete bunkers for safety purposes. No extensive safety precautions are needed. The rockets are launched electrically from 10 to 15 feet. Each model rocket contains a recovery device such as a parachute, streamer or other high drag mechanism. The models are returned safely to the ground so that they can be flown many, many times. Some model rockets have been sent aloft as many as 100 times.

11/29/69

Monday 24 August 2020

United Press International Photo 1969


This beautifully evocative vintage image, taken at Goddard Space Flight Center in Greenbelt, Maryland, is a United Press International photo, dated November 29, 1969. There's a candid immediacy to the scene depicted; it conveys a familiar sincerity and enthusiasm most of those who were teenagers captivated by model rocketry during the 1960s or 1970s (such as the author of this blog) will immediately remember.

It's fun to rummage visually through the details in this picture to discover items one is familiar with. The most obvious being the rockets, of course, such as the main body, clear payload section, and nose cone of a Centuri Payloader II in the grass, the Estes Astron Camroc camera nose cone in the boy's hand, or the Centuri (or Estes?) Apollo Little Joe II in the cardboard box at right. Next to the boy's left foot is a Centuri 1967 model rocketry products catalog, quite a collector's item today, all these years later.

The press text attached to the rear of the original photo reads as follows:

WAP 1613620

MODEL ROCKETRY

GREENBELT, MD: With the equipment and tools necessary to build a model rocket, a member of the National Association of Rocketry is busy assembling his latest creation. Each year, the NAR sanctions contests throughout the United States in preparation for the National Model Rocket championships, also sanctioned by the NAR. Model rockets are constructed of paper, balsa wood, and breakable plastics and contain no substantial metal parts. The rockets are powered by commercially manufactured propellants of proven reliability and performance.

11/29/69

Monday 3 July 2017

Completed Enerjet 1340/20 & 1340 Replicas



This is the result of having come to terms with the realization that I couldn't bear living my life without ever having owned the iconic Enerjet 1340 and, particularly, 1340/20 rockets we so admired as teenage model rocket enthusiasts. After finally being able to track down all of the necessary components from overseas, and after investing a few weeks of work, these are the finished Enerjet 1340/20 (left) and 1340 replicas.

The young teenage me would have loved this sight. As, indeed, the current me does as well. What beautiful, clean, and functional designs these are; very vintage 1970s and yet - in my view - not detrimentally dated at all. As mentioned previously, I closely adhered to Enerjet's original specifications in building these rockets. Among the very minor amendments to the original designs are, for example, pressure equalization openings in the nose cones, in order to make it feasible to carry altimeters.

It is currently somewhat difficult to mentally grasp that this brings to a conclusion a personal ambition that has existed for over four decades.


Enerjet 1340 and 1340/20 flyer images © by Enerjet Inc., Phoenix/AZ, USA.

Friday 30 June 2017

Enerjet 1340/20, Part 3



Due to the nature of the components and construction of the Enerjet 1340/20 replica, I pre-painted the sub-sections of the rocket before assembling them and applying glue. I have rarely done this before - if ever - but it made attaining the original 1970s Enerjet paint scheme far easier. I also applied the same procedure to my Enerjet 1340 replica, conceived and begun slightly ahead of the 1340/20.

After the final step of installing the 29 mm motor mount, which was left protruding from the rear end of the airframe as per the original design, both rockets were ready for a gloss coat and decaling. As stated in an earlier post, my stock of original Enerjet waterslide decals had dwindled to a mere few logos, and I therefore ordered a few sheets of custom made replica decals. As it happened, however, one of the remaining original decals fit the 1340/20 replica perfectly, matching the size of the decal seen on the rocket in Enerjet's 1970s photos. I thus used the new decals only on the 1340 replica, again striving to make it look as visually authentic as possible. Decal setting solution was needed to achieve a good sit of the delicate decals.

Thursday 29 June 2017

Enerjet 1340/20, Part 2



In building my Enerjet 1340/20 replica, I largely followed the original design as shown in Enerjet's 1340/20 Sounding Rocket flyer of the 1970s. For example, I installed a 29 mm motor mount but concurrently also constructed a dedicated, removable 24 mm adapter for use with this rocket. A small deviation was made with regard to the parachute material; instead of the original two 12" silk parachutes, I used a hexagonal Rogue Aerospace PP-45 (45 cm diameter) nylon parachute and chose a combined recovery of airframe and payload section.

The most significant difference to the original 1340/20 rocket is the launch lug. Enerjet had fitted the rocket with wire loops for guidance during launch. While this likely made sense aerodynamically, I always felt unsatisfied when looking at the iconic 1970s photos prominently showing the #13 plastic fin unit's integrally moulded launch lug left without any purpose on the front side of the rocket. This was a design decision I didn't quite comprehend. I thus modified the top section of the moulded launch lug to hold a plywood stand-off, on which I later glued the lower of two conventional launch lugs. This worked flawlessly and left the front aspect of the rocket pleasantly uncluttered.

Epoxy adhesive was used throughout the construction of the rocket.

Wednesday 7 June 2017

Astron Alpha Recovery



The fourteen year old me holding my freshly recovered Estes Astron Alpha after the launch seen elsewhere on this blog. This particular model was an early-style Alpha, featuring balsa wood fins and nose cone.

As noted in the aforementioned earlier post, this rocket was likely a self-made clone, as evidenced by what seems to be a Centuri parachute. I built a number of Astron Alphas of all incarnations, both from official Estes kits and as self-made replicas. It soon became a tradition to initiate launches with an Alpha, in order to determine wind conditions before switching to larger models.

Photographed by Hans Hofer in northeast Switzerland, in July 1978.

Saturday 3 June 2017

Handbook Of Model Rocketry



Another quest that proved a slightly more challenging than anticipated was my aspiration to find those editions of G. Harry Stine's Handbook Of Model Rocketry that my enthusiastically completist mind perceived as still dreadfully missing.

I first purchased the Handbook in its fourth edition in 1976 or 1977, and the latest, seventh edition is still readily available at the time I am writing this. We were utterly excited - rightly so! - about the Handbook when we first received it, and I thus also purchased any subsequent editions throughout the years. But obtaining the earlier and therefore historically rather fascinating editions was near impossible from Switzerland before the advent of the internet. And, as I found out, it can at times be somewhat difficult even today.

While I eventually found a copy of the second edition in decent condition, it was due to the extremely generous efforts by American collector Steve Kristal that I was able to complete the long-coveted line-up of books by adding the first and third editions. Needless to say, I am deeply grateful for such kindness.

For somebody who has been fascinated by model rocketry for most of my life, this means a lot. G. Harry Stine's Handbooks are not mere collector's items to me; it is still quite fascinating to read them, and the information therein has aged quite well. These books are like a time machine to an era when model rocketry lived through a golden age.

The photo above thus shows all the editions in chronological order. Top row, from left: Handbook Of Model Rocketry, original edition, Follett Publishing Company, Chicago, 1965; second edition, Follett Publishing Company, Chicago, 1967; third edition, Follett Publishing Company, Chicago, 1970; my original copy of the fourth edition as purchased when I was a teenager, Follett Publishing Company, Chicago, 1976.

Bottom row, from left: fifth edition, Prentice Hall Press, New York, 1987; sixth edition, John Wiley & Sons, Inc., New York, 1994; seventh edition (with Bill Stine), John Wiley & Sons, Inc., New Jersey, 2004.

Tuesday 30 May 2017

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.

Friday 4 November 2016

Vehicle 76



The design of Vehicle 76, a sport model with payload section, is loosely based on the smaller Vehicle 9, previously covered here. Vehicle 76 was built in 1999, using various Vaughn Brothers, Estes, and Aerotech components. It utilizes plywood through-the-wall fins with a thickness of 2.3 mm. It measures 650 mm in length and 66 mm in diameter and is intended to be flown with 29 mm F and G composite motors.

The nose cone, 205 mm in length, conceals a tubular payload section with a length of 180 mm and a diameter of 42 mm. At the time, it was tailored to the altimeter I used most often, the Missile Works RRC2. The payload section is fully removable, for ease of altimeter access. The rocket is recovered by means of two silk parachutes.

Top photo shows Vehicle 76 in Zurich, Switzerland, in 2016. Lower photo was taken in Thalwil, Switzerland, after completion of the rocket in summer of 1999.

Thursday 3 November 2016

Vehicle 22 Redux



The evolved version of the original Vehicle 22 payload model rocket, Vehicle 22 B, while being prepared for launch from my metal theodolite launcher at Allmend Frauenfeld, Switzerland, on Saturday, April 26, 1986.

Vehicle 22 B flew with a Flight Systems Inc. 21 mm black powder D or E motor. And while my flight data sheet of that day indicates a very good deployment of the parachute and a perfect post-flight condition of the rocket, the flight itself is described by means of a brief, wry remark: "stability deficiencies".

Photography by Martin Kyburz.

Wednesday 2 November 2016

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.

Monday 31 October 2016

N Project: 4" Glass Fibre/Carbon Fibre Rocket, Part 3



Top photo: Professor Eugene Trubowitz is examining one of the fresh arrived Rocketman parachutes at the machine shop of the Swiss Federal Institute of Technology in Zurich, Switzerland, in late summer of 2000. All three rockets of the N project used Rocketman main und drogue parachutes.

Second photo from top: the two custom threaded forward closures of the Dr. Rocket 98 mm aluminium motor cases used for the two 4" rockets of the project. We were very fortunate to be granted to use the tool machines of the Institute for any such special modifications required in the course of our project.

Lower two photos: first trail assembly of the electronics compartment for the 4" glass fibre/carbon fibre rocket. The design of the electronics compartments for both 4" rockets was identical. The mounting base for the electronics thus consisted of an aluminium ring/shoulder, screwed to the modified forward closure. This arrangement further provided a mounting point for the glass upper airframe section.

The circular white insulation foam disc was intended to shield the electronics from the head emitted by the subjacent N2000 composite motor. Again, four threaded steel rods served to hold four custom- made aluminium mounting bridges, to which the two BlackSky AltAcc dual deployment recording accelerometers would subsequently be attached.

Sunday 30 October 2016

N Project: 4" Glass Fibre/Carbon Fibre Rocket, Part 2



Further images depicting the construction of the 4" glass fibre/carbon fibre N-motor rocket built for the BALLS 10 experimental launch held at Black Rock Desert in Nevada, in 2000. Top photo shows the custom made carbon fibre 4" nose cone with glass shoulder and steel tip. This beautifully immaculate cone was manufactured by Swiss Composite, based on calculations by Professor Eugene Trubowitz.

Centre photo shows Professor Trubowitz working on the rocket while we were performing a first trial assembly of the full (but still incomplete and unpainted) vehicle at the machine shop of the Swiss Federal Institute of Technology in Zurich, Switzerland. Components of the other two rockets of the N project can be seen to the right: the red and silver 4" aluminium/glass fibre/carbon fibre rocket with its welded aluminium fins and, at lower right, a section of the carbon fibre fin can of the 6" glass fibre/carbon fibre rocket.

Lower photo shows the 4" glass fibre/carbon fibre N-motor rocket erected vertically for the first time, in mid-September of 2000. The red Dr. Rocket N2000 98 mm aluminium motor case can be faintly seen through the lower glass fibre airframe section. The steel tip of the nose cone is provisionally held in place by masking tape; it would later be secured internally by means of threaded steel rod.

Thursday 20 October 2016

Vehicle 79 (Redux)



Vehicle 79 Dominator III ranks among my favourite rockets in my fleet. It is an uncomplicated rocket to fly, and its simple design provides a consistently impressive performance on F and G composite motors. Vehicle 79 was constructed from a variety of US Rockets and Aerotech components, featuring through-the-wall plywood fins, a custom-made aluminium baffle unit, and a payload section with a length of 315 mm. Top photo was taken at my former workshop in Thalwil, Switzerland, on November 22, 2010.

Lower photo shows Vehicle 79 on a friend's aluminium launch pad, on the occasion of our "last launch of the century", held on December 22, 1999, in northeast Switzerland. We flew our rockets from 2 to 5:30 pm; the temperature fluctuated around the freezing point. This was our seventh flight that day and thus our last flight of the launch and of the century. Vehicle 79 was powered by an Aerotech 29mm F20-7W Econojet motor. The payload flown consisted of a Missile Works RRC2 altimeter and a custom 9V piezo sonic locator. The flight was perfect and loud, and the RRC2 indicated an altitude of 1274 ft.

Monday 17 October 2016

1972 Enerjet Catalogue






Sample pages from the unique and intriguing 1972 Enerjet advanced rocketry model products catalogue (no. 721).

As deeply curious and utterly determined teenagers building model rockets in remote (from a consumer point of view) Switzerland in the mid to late 1970s, we were continuously driven towards increasingly advanced rocket concepts and the quest for rocket motors more powerful than the commonly available A, B, C, and D-class motors. Mind you, it was far from granted to find even such "regular" motors in Switzerland at the time. Our ambitions were satisfied to some extent when a German distributor brought the product line of Flight Systems Inc. to our hemisphere and we were finally able to obtain their range of D, E, and F black powder motors.

In our minds, however, Enerjet represented the holy grail of advanced model rocketry, and it therefore served as the underlying inspiration for many of our own projects. This was of course long before readily available information by means of the internet, and even though Enerjet was no longer trading as an active company by that time, the company, for us, was thus an entity equally shrouded in mystery and emitting a limitless fascination. The few things we knew about Enerjet had been glanced from pictures in books (the Handbook Of Model Rocketry) and Centuri brochures, or from the remnants of Enerjet's existence as evident in Centuri's catalogues.

I would have given anything to own the 1972 Enerjet catalogue at the time (or to even be granted to have a brief look at it), but any such publications remained unobtainably elusive for us two rocket obsessed adolescents in Switzerland. Only much later in my life was I finally able to obtain a pristine original edition. The infinite waiting period mattered little; Enerjet's very existence and iconic designs still represent the same captivating inspiration to me to this very day.

The above excerpts from the 24-page catalogue show, for example, Enerjet's revolutionary "port burning" composite motors with glass fibre casing, or the fantastic (and operable) Nike Smoke semi scale rocket (vaguely similar to the Centuri kit) and Nike Ram high altitude payload rocket.

1972 Enerjet catalogue sample pages © by Enerjet Inc., Phoenix/AZ, USA, 1972, scanned from my personal copy of the catalogue.

[Entry amended October 31, 2016; with thanks to Chris Michielssen.]