Heinkel He 178

Hay Shifty, you might want to read this to find out a short history of the jet engine. It was the Wright brothers who realized that an efficient propeller or "air screw" was not just a paddle that pushed air to the rear of and aircraft. To work properly it should be an airfoil, causing the pressure on the front surface of the propeller to be less than the pressure on the back surface, creating forward thrust. However, as a propeller blade approaches the speed of sound, it losses efficiency. Because of this, there is a practical limit on the speed a propeller driven aircraft can achieve. Frank Whittle learned this fact of aircraft propulsion at the No 2 School of Technical Training RAF Cranwell. To get around this limit he figured you could propel an aircraft with a reaction engine instead of a propeller. One type of reaction engine is a rocket engine, but because rockets must carry an oxidizer as well as a fuel, they are limited in their endurance. On the other hand if you make a reaction engine that uses the oxygen in the air combined with fuel to burn and generate pressure at the rear of an aircraft, you would have a reaction engine with acceptable endurance that was not limited in speed by an external propeller blade. In a turbo jet engine you might say the "propeller blade" is replaced by impeller blades inside the engine that draw in and compress the air inside prior to the introduction of fuel and ignition. Other blades at the rear of the engine are pushed by the hot pressurized exhaust gases and rotate the main shaft to keep the forward "compressor blades" moving to replete the process. Because these internal blades are not acting as airfoils to propel the aircraft themselves, they do not have the inherent limitation that external propellers have when it comes to speed. Whittle used a centrifugal type of impeller, (much like a turbo charger or you swimming pool pump) at the front of his jet engine to pressurize the incoming air. Meanwhile Dr Hans Pabst von Ohain in Germany had been working along similar lines, but in the German approach it was a set of inline impellers that were used to do the compressing. Both systems worked, but the German type, called axial flow, was more adaptable to larger engines and is the type used today, (with the centrifugal type if you want to make a more powerful engine you must increase the diameter of the impeller, and the diameter of the engine; but with the axial flow engine you can add impellers, one behind the other and only make the engine longer and not much wider). One problem the Germans had with their early jet engines was that the high internal heat of jet engines rapidly deteriorated the metal impeller blades at the rear of the engine, shorting their life. The British, and later the Americans, had access to better "exotic" metals to overcome this problem. The USSR first used captured German engines and technology in their early jet aircraft. What really got them up to snuff with the West was when the British, for some still unexplained reason, gave the Soviet government a number of the latest Rolls-Royce Nene engines. That was the engine that made the Mig15 such a great aircraft. As for the Russians inventing everything, I remember in the 1950's when the Russians claimed that Christopher Columbus acquired a map from a dying Russian sailor showing him the way to America!

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with the narrow air intake they used the cool morning air to get sufficient volume of combustion air (oxygen) into the jet engine for a safer flight.

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I found the Concord 1 /43rd scale kit of the He-178 at Frontline Hobbies in Newcastle and it caught my eye. I haven't started it yet, not that there is all that much to do, but I am looking forward to it. Heinkel was a guy I have much admiration for.

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Sure, Shifty, the Russians were first in everything, and if they could not build something first, they had to build it the biggest. A bit of documentation to back up your assertions would be welcome.

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Actually the Russians were the first to develop turbojet technology but who ever would give credit to commies?

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ERIK WARSITZ`S SON LUTZ LIVES IN SWIZTERLAND AND PUBLISHED RECENTLY A BOOK ABOUT HIS FATHER :"ERIK WARSITZ THE FIRST JETPILOT " IN ENGLISJ WLK

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Very interesting aircraft in so far as it was flyable in the late thirties, max speed of over 400 MPH, and of composit material why was it not developed for the war effort?

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Importantly, the Germans beat Britain into the air with this, the first jet, even though Whittle first had ideas as early as 1929. Nice little 'plane!

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It's 70 years today after the historical flight of this experimental aircraft at 4 o'clock in the morning. Probably because of difficulties with the narrow air intake they used the cool morning air to get sufficient volume of combustion air (oxygen) into the jet engine for a safer flight.
Best regards from Germany

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