This part is wandering away from the central theme of the website, one might say. Yes, it’s true, but I believe that you will find worth the while a short stop in this section.
This page tries to bring you the history and evolution of the Turbonique, from its early days in Orlando, Florida (U.S.A) around 1962, an overview of the various applications the firm proposed and marketed throughout the sixties, mainly for the US home market, and their various creations most of the times more of a publicity operation than of a research nature.
The wide range of products proposed by Turbonique was based on three propulsion systems: the engines (that were called microturbo engines), the superchargers and the thrust engines, which were in fact rocket nozzles. All of them were designed to operate with a propellent called Thermolene, about which I write some lines further on in this webpage.
The microturbo engines, in this case, were rocket engines. What are the differences between a rocket engine and a jet engine ?
A rocket engine burns a fuel together with an oxidizer in a chamber. The fast combustion that follows is expelled freely through a nozzle and a high thrust is thus obtained. There are no moving parts and it can run in the absence of air (underwater or in outer space, for example).
A jet engine is composed of two parts: an axial flow compressor that pushes air under high pressure into a chamber where a liquid fuel is injected and ignited. The combustion of the fuel in the presence of the oxygen contained in the air fed by the compressor creates a rise in volume and hence of the pressure that is expelled through a nozzle where another turbine is installed. This exhaust turbine is thus driven by the exiting jet and its hi-rev spinning movement is used to move the compressor, as both compressor and exhaust turbine are mounted, in general, on the same axe. The jet engine has moving parts (the turbines revolving around the shaft) and uses lots of air to ignite and run. An excellent website to visit if in search of more information on jet engines is microjeteng.com
What is this go-kart doing in the middle of all this ? Well, it is a turbonique rocket propelled kart, these little devils turned out amazing short times on the drag racing strips in the sixties. One such kart was found recently, his new owner - a go-kart enthusiast - proudly shows it in his website http://www.rocketkart.com/
Here is a phrase from his site "According to all accounts this kart went from zero to 150mph in 4 seconds before becoming airborne and sliding out of control." Please feel free to click on the picture above and enter a new page I created with information about that kart and about Turbonique, the company.
The engines proposed by Turbonique Inc. were turbine driven engines. These were, seen from the perspective of our 21st century, quite rudimentary. They consisted basically of a carefully designed circular chamber (snail housing) where a rocket type burner was ignited and the thrust of the burned gases was used to make a turbine spin at high revs. This movement was converted into a more useable power source by means of a reduction gear. The turbine reached speeds of 92,000 rpm. The reduction gear brought this movement to a more useable 5750 rpm speed with astonishing high torque output. The micro-turbo engines were really powerful !
It must be stressed, on the passage, that the Turbonique applications had, in general, a very short running time span: the thrust engines could run for one or two minutes, the superchargers for a little longer period (up to about 10 minutes) and the microturbo engines not much more than that. This was due to various factors:
a) The temperatures obtained were very high. Components would overheat and break or melt away if under prolonged use.
b) The fine tuning of the propellent amount injected in the device was difficult to control. Turbonique gear worked mostly on a "all-off" "all-on" pattern with instantaneous accelerations. With present days digital controls the operation of these machines would have been more "user friendly".
c) The fuel containers had a limited capacity.
It was not more nor less dangerous, flammable and prone to evaporation than gasoline. It could be stored in jerrycans, in the shadow. It had, nonetheless, some peculiar side effects: it was irritating to the skin, it would melt most plastics, rubbers, etc. and it would react under certain circumstances if in contact with some metals, like mild steel, in the presence of water. Thermolene disappeared with the extinction of Turbonique in 1967-68 but the liquid as such can still be bought under its chemical denomination, N-Propyl Nitrate, from a chemicals supplier. If you just ask for thermolene you will be proposed some kind of plastic, as the name has been adopted and patented by the plastics industry, since.
The big advantage of Thermolene was its great propulsion power. The combustion was so intense that no subproducts would result besides the hot gases: no smoke, no ashes, no black deposits ... power only !
Now that this short presentation has been made it will be easier to understand how the various Turbonique propulsion systems worked. The Turbonique C-2-A supercharger that is part of my collection (the only existing one in Europe and quite likely the only NOS one in the world) will be reviewed in a more detailed section in the next upload (in some few weeks time) while I will continue unfolding this extraordinary story by presenting you the Black Widow.
The Black Widow : the exciting story of a record breaking VW loaded with speed, innovation and adventure.
What first stroke me when I started getting interested by this famous car was the absence of information on it. Her life was too short, she lived and raced like a lightning. Her origins and her final days remain a mistery.
The Black Widow was prepared to race on the simple basis of commercial advertisement. She was meant to show the flag of Turbonique Inc. on the racing strips.
Why was a VW oval chosen for this purpose ? Low cost would probably be the answer but the popularity of the model could also have played a role here. On more, Turbonique had developed the jet powered transmission for VWs, model S-10-A, a technical break through that needed to be tested neck-to-neck against more conventional propulsion set-ups. The other products of the company (go-karts, thrust engines, superchargers , etc.) were selling well in those mid-sixties and in the USA everyone in the racing community was impressed seeing Joe Vittone’s VW Inch Pincher sweep race after race (see Shorrock).
In this respect, the Black Widow might have shadowed the records set by VW race cars on the West Coast.
Unfortunately, in October1966, a bad crash left the Black Widow in a shape beyond repair and after that the trace of the car was lost. Quite probably it was scrapped. The company went through various difficulties and in a matter of months ceased to exist.Only the record remained, a flared 9.36 at 168 mph in Sept.19, 1966, at NHRA Tampa Dragway.
Given the very particular mode of propulsion, this car could only operate for short runs of approximately 20 to 60 seconds. The termolene fuel supply set-up was located in the front luggage compartment.
Unless nowadays jet engine dragsters and tractor-pullers who warm up their engines on the starting line before giving an all-out roar at the green light, the Turbonique powered cars had no warm up: start push and full throttle was all done at once. The crowds really turned wild when they saw the car pass from total inert and silent condition to record breaking speeds, leaving hi-powered competitors in embarrassing situations.
The Black Widow was a project launched in a more serious style than a white oval VW that preceded it and on which several trials were made.
As a result of this previous experience, the Black Widow had a parachute braking aid, large slicker tires and the suspension was reinforced. His pilot, Roy Drew, featured in an advertisement page of Turbonique Inc. in some motoring magazines of that time posing against the crashed dragster.
The fuel installation
The propellent installation for a Turbonique engine requires several elements, hereafter detailed in blocks:
A) 3 containers: a high pressure cylinder containing oxygen (needed for starting the flame only), another high pressure cylinder containing nitrogen, equipped with a regulator valve. This nitrogen is injected into the third cylinder so as to create a high pressure inside it that will expel the Thermolene towards the burner in the engine. The third cylinder (the fuel tank, so to say) is normally the biggest of all three and, once the pressure released, can be opened to refill with Thermolene. This third cylinder has to be upright all the time whilst the two other can be laid down on their side.
Thermolene was the trade mark under which Turbonique Inc. marketed N-Propyl Nitrate. It was sold in 8 pound cans at a retail price of $ 12. A 475 pound drum would have cost you $ 437 back in 1966. In itself not more hazardous liquid than gasoline or kerosene, it had, nonetheless, far more energetic yield.
B) High pressure solenoid valves and piping: An on-off solenoid valve placed on the oxygen line close to the turbine burner or the engine chamber. A hand valve to set the operation pressure inside the Thermolene tank. A solenoid operated valve to open or close the Thermolene supply into the burner spout (the shut-off valve). One pipe from the O² cylinder to the engine. One pipe from the nitrogen cylinder to the thermolene tank. One pipe from the Thermolene tank to the engine.
C) Electric wiring and switches. One switch sets the electrical system under tension in ignition stand-by, a second switch triggers the flame. Another device, called the control unit, is in fact a box containing the necessary solenoid contacts and connections to open the oxygen and the thermolene inputs and, after a preset time gap, cut the oxygen arrival. For the micro-turbo engine and the superchargers, the ignition was made using a mere spark plug that was, in the case of the chargers, plugged to the coil hi-tension output. This spark plug was placed right in front of the thermolene feeding spout, in the flame chamber. The continuous spark of the plug kept up a "flowing explosion".
For the correct and safe operation of a Turbonique propulsion system it is paramount that the electrical side be operated under generous current supply and that all cabling, connectors and moving parts be in optimal operating conditions.