see g harry stine “the coanda effect” analog magazine july 1984
pgs 62-75

“….when operating , the compressor sucks in air and compresses it inside the large cylinderical cowling. the engine’s exhaust is routed into this compressed air where it’s enriched by a spray of raw gasolien and then ignited. the resulting hot high-speed gases are then ducted to the rear out of two asbestos-lined jet pipe, one on each side of the molded plywood fuselage… it produced a static thrust od 220 pounds….”

ming

All attempts to use the pulse jey as a practical propulsion for a manned aircraft failed (with the possible exception of the 1945 Riechenberg suicide aircraft which was merely a piloted V1) mainly because of the extreme vibration created by this engine. The Germans did build an emergency fighter using two pulse jets but soon abandoned the jets and converted the aircraft into suicide gliders (not deployed). In attempt to boost the performance of the P51D Mustang (to meet the threat of the new jet fighters) the Americans fitted one with pulse jets, one on each wing tip, again vibration caused the abandonment of the project. Putting pulsejets on an aircraft with WW1 construction standards would have been a disaster

Thanks for a very good read, and this information. I will be reading more of your site now that I have found it.

Again, thanks for this enlightening information.

The “air-reactive engine”, invented and built for the first time by Henri Coanda, composed of a piston-engine with four cylinders, cooled with water; it developed 50 HP (Horse-Power) at 1000 rotations/minute. This piston-engine was connected to a rod which rotated the rotation multiplier; the movement was transmitted to the compressor which gained a rotation speed of 4000 rot./min.. In front of the compressor was placed the obturator - a device very similar to that of a photo-camera; this device could be controlled by the pilot such that the quantity of air that entered the compressor could be regulated. The air entered the burning rooms, (that had a ring-like section and were placed on both sides of the fuselage), from which, through some tubes, burned gases of the engine were evacuated and the propulsion force was generated.

This seems to describe the combustion of a fuel-air mixture, which would provide much more thrust than just a jet of compressed air would.

But, most of the descriptions on the net seem to be drawn from the same source (a post to a Romanian mailing list - although it does list further sources). Now, I’ve had a look in my Gibbs-Smith and here’s what he has to say:

it was equipped with a reaction propulsion unit consisting of a 50-h.p. Clerget engine driving a large ducted fan in front of it, the latter enclosed in a cowling which covered the nose of the machine and part of the engine: the fan was a simple air-fan driving back the air to form the propulsive ‘jet’.

Charles H. Gibbs-Smith, Aviation: An Historical Survey from its Origins to the End of World War II (London: Her Majesty’s Stationery Office, 1985), 156.

This sounds like merely a jet of air! So who is right? It might be that Gibbs-Smith is missing something here, as he says the Coandă-1910 was ‘inevitably earth-bound’, which suggests to me that he was not aware of Coandă’s claim to have flown it briefly. But going against Gibbs-Smith is a tough call …

So now I don’t know!

PS Interesting about the pulsejet, I didn’t realise it was around so early.

Chuck in the advantage of only having one moving part, and you’ll see why this design lags a true jet.

Interestingly enough, the pulse-jet (as in the V1) *had* been invented then - it’s just never been very efficient. It would have been a far better candidate for a WW1 jet. though. The real limiting factor on gas turbines was metallurgy - everyone had been aware that a gas turbine would be a good idea for years, but the science of high temperature alloys was lagging. Frank Whittle was convinced this was really because nobody had tried to do a gas turbine yet…which turned out to be the truth.