Some origins of German jet power
 
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Jet Propulsion
 
  Jet propulsion
  Of cource, there were a number of people who recognised that jet propulsion would supersede piston-engine propulsion for high-speed flight in the future while the gas turbine, being entirely rotary, was capable of higher speeds and powers than the reciprocating piston engine.
  Eventually, all the main aero-engine companies, plus some others, worked on jet engines in accordance with a programme laid down by Schelp and his staff in the German Air Minstry. Of these companies, BMW was the first to begin work on a turbojet in 1938 (Kurt Loehner’s P.3303 centrifugal engine) which Bramo followed in the same year by building a piston-driven ducted fan engine and beginning the design of an axial turbojet (later designated P.3302). When in the summer of 1939, Bramo was taken over by BMW, a complicated counter-rotating axial turbojet project from Helmut Weinrich was also begun under the designation P.3304 or 109–002.
  HeS 3B
  July of 1939 saw the first flight tests, using an He 118, of von Ohain’s HeS 3B centrifugal turbojet.
 
HeS 3B
Cutaway view of the Heinkel HeS 3B in the Deutsches Museum. Picture shows a rebuilt example after the war.
 
 
HeS 3B
In 1939 the HeS 3B produced a thrust of 450 - 500 kp. The axial low-pressure compressor had eight blades while the centrifugal-flow compressor had 16.
 
  He 178
  A second HeS 3B was fitted to the He 178 prototype which made the first true purely on turbojet power on august 27, 1939. Although no spectacular performer, the succes of the He 178 made an enormous impact on the RLM and swelled the ranks of jet aircraft protagonists.
 
He 178 taxiing
He 178, seen while taxiing during flight testing in 1939.
 
 
He 178 in flight
He 178, in flight 1939.
 
  By now, the Junkers engine division had accepted a contract to develop an axial turbojet engine (origins of the 109–004) while even the conservative Daimler-Benz company had decided to enter the files with paradoxiacally, a complicated counter-rotating, ducted-fan turbojet (109–007).
  BMW’s P.3302 turbojet evolved into the 109–003 engine and this, with Junkers 109–004, were to become the two more developed and therfore most used turbojets for Germany in the later war years.
  Pulsejet & Ramjet
  Before leaving 1939, we must observe that the Argus company had begun making pulsejet tests (later it was to overtake Schmidt’s work) while the first unsuccessful firings of Trommsdorf ramjet accelerated missiles were made. Work at the pionieering Heikel company had taken a bad turn by 1940, since instead of concentrating on the pursuance of von Ohain’s ideas, efforts were spread over a number of other projects including piston-engine ducted fans (eg HeS 50 and HeS 60) and axial turbojets (eg HeS 30 and HeS 40) which were under the direction of Max A. Mueller who had arrived from the Junkers airframe division at Magdeburg.
 
HeS 30
The HeS 30 produced a thrust of 820 kp on its test platform in April 1942.
 
 
Drawing of HeS 30
Drawing of HeS 30.
 
 
Drawing of HeS 40
Drawing of HeS 40.
 
  HeS 8 & Hes 30
  Among the new Heinkel projects, specially interesting were von Ohain’s HeS 8 (or 109–001) centrifugal turbojet and Muller’s Hes 30 (or 109–006) axial turbojet; the HeS 8 was the first Heinkel turbojet to receive afficial backing but both engines were earmarked as alternative powerplants for the world’s first turbojet aircraft designated as a fighter, the twin-engined He 280.
  Developed from the previous HeS 6 of 550 kp (1213 lb) thrust, the HeS 8 was designed for a thrust of 700 kp (1544 lb) but development was protracted and this thrust was never reached.
 
HeS 6 drawing
Follow-up development of the HeS 3B, the HeS 6.
 
 
HeS 8 drawing
Developed from the HeS 6, the HeS 8.
 
  Not until 1941 was the HeS 8 ready for flying when two such engines powered the He 280 protoype for its maiden flight on april 2. Another two years were to pass before more HeS 8 engines were ready for the V2 and V3 prototypes of the He 280 but by then the engine had been overtaken by other developments.
 
He 280 V1
The Heinkel He 280 V1 taking-off on the first flight on April 2 1941. The aircraft was designed as a potential fighter. The two HeS 8 turbojets were left uncovered on the first flight. The He-280 V3, GJ–CB.
 
  By contrast, the Hes 30 engine made dramatic progress, was developing some 860 kp (1896 lb) of thrust by october 1941, and showed every promise of substantially increasing this thrust. Inexplically, however, the engine never flew since it was officially abandoned for obscure technical reasons and because it was considered to small for future requirements. Instead, the order came at the end of 1942 for the Heinkel company (which had now absorbed the Hirth engine company) to concentrate all its jet engine staff upon the development of a new 1300 kp (2866,5 lb) thrust engine with a diagonal compressor and designated the 109–011. The idea was that the 109–011 would be a second-generation engine leaving BMW and Junkers to develop the first-generation engines. Both these companies had prototypes for their engines running by the end of 1940 but they were far from satisfactory and enormous difficulties remained to be solved. The nature of these difficulties encompassed aerodynamic thermodynamic and mechanical problems and can scarcelly be touched upon here.
 
HeS 011
The HeS 011 was designed for a thrust output of 1600 kp, by the end of the second world war the thrust output was 1300 kp.
 
 
An abortive attempt was made in March 1942 to fly the prototype Messerschmitt Me 262 V1 with two BMW 003 turbojets (P. 3302), still with its nose mounted piston engine.
At an altitude of 165 ft both turbojets flamed out and it was discovered that the compressor blades in both engines were broken. The BMW 003 had to be entirely redesigned, and the revised power plant, the BMW 003A with a greater mass flow, was not destined to fly until October 1943, and then beneath a Ju 88A test bed.   
Ju 88A with BMW 003
The Ju 88A-5 illustrated above seen in service as a BMW–003 turbojet test aircraft
 
P.3302
P.3302 experimental engine, which initially (1940) had a thrust of 260 kp in the test chamber, but due to numerous improvements this was boosted to 500 kp.
 
 
Me 262 V1
Me 262 V1, werknummer 262 000 01, PC + UA, with Jumo 210 in the nose, photographed during installation of the BMW P.3302 engines near the end of 1941.