Heinkel HeS 3
Encyclopedia
The Heinkel HeS 3 was the world's first operational jet engine
Jet engine
A jet engine is a reaction engine that discharges a fast moving jet to generate thrust by jet propulsion and in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets...

 to power an aircraft. Designed by Hans von Ohain
Hans von Ohain
Hans Joachim Pabst von Ohain was a German engineer, one of the inventors of jet propulsion.Frank Whittle, who patented in 1930 in the United Kingdom, and Hans von Ohain, who patented in 1936 in Germany, developed the concept independently during the late 1930s...

 while working at Heinkel
Heinkel
Heinkel Flugzeugwerke was a German aircraft manufacturing company founded by and named after Ernst Heinkel. It is noted for producing bomber aircraft for the Luftwaffe in World War II and for important contributions to high-speed flight.-History:...

, the engine first flew as the primary power of the Heinkel He 178
Heinkel He 178
|-See also:*List of firsts in aviation-Bibliography:* Warsitz, Lutz: The First Jet Pilot - The Story of German Test Pilot Erich Warsitz, Pen and Sword Books Ltd., England, 2009, ISBN 9781844158188.-External links:...

, piloted by Erich Warsitz
Erich Warsitz
Erich Warsitz was a German test pilot of the 1930s. He held the rank of Flight-Captain in the Luftwaffe and was selected by the Reich Air Ministry as chief test pilot at Peenemünde West...

 on 27 August 1939. Although successful, the engine had too little thrust to be really useful, and work started on the more powerful Heinkel HeS 8 as their first production design.

In some ways the HeS 3 design was simply a cleanup of the original HeS 1
Heinkel HeS 1
The Heinkel HeS 1 was Germany's first jet engine, which was a stationary test item that ran on hydrogen.-History:In 1933, Hans von Ohain wrote his PhD thesis at the University of Göttingen on the topic of an optical microphone that could be used to record sound directly to film. Siemens bought the...

, converted to burn liquid fuel instead of the HeS 1's hydrogen gas. von Ohain was also unhappy with the large external diameter of the HeS 1, and re-arranged the layout of the new engine to allow the parts to be "folded together" in a more compact layout.

The first HeS 3 design was generally similar to the HeS 1, using a 16-bladed centrifugal compressor
Centrifugal compressor
Centrifugal compressors, sometimes termed radial compressors, are a sub-class of dynamic axisymmetric work-absorbing turbomachinery.The idealized compressive dynamic turbo-machine achieves a pressure rise by adding kinetic energy/velocity to a continuous flow of fluid through the rotor or impeller...

 supported by an 8-blade impeller to smooth out the airflow in the intake. The compressed air flowed into an annular combustion chamber arranged to lie between the compressor and turbine, which were separated much more than in the HeS 1 to allow this arrangement. The first example was bench tested around March 1938, but the arrangement led to a smaller than useful compressor and poor combustion.

A redesign started as the HeS 3b, which dispensed with the "folded" arrangement and returned to simpler flame cans for combustion. In order to keep the dimensions small, the widest part of the cans were arranged in front of the engine, the compressed air first flowing forward into the cans, and then rearward to the tubine. Although not as compact as the original design, the 3b was much simpler. Designed to run on gasoline, the fuel flow was preheated by running it over the rear roller bearing.

The engine was completed in early 1939, and was flight-tested under one of the remaining Heinkel He 118
Heinkel He 118
-See also:-References:* Green, William. Warplanes of the Third Reich. New York: Doubleday, 1972. ISBN 0-385-05782-2....

 dive bomber
Dive bomber
A dive bomber is a bomber aircraft that dives directly at its targets in order to provide greater accuracy for the bomb it drops. Diving towards the target reduces the distance the bomb has to fall, which is the primary factor in determining the accuracy of the drop...

 prototypes. The flight tests were carried out in extreme secrecy, taking off and landing under propeller power, and only flying in the early morning before other workers had arrived. Testing proceeded smoothly, but the engine eventually burned out its turbine.

A second engine was completed just after completion of the He 178 airframe, so it was decided to move directly to full flight tests. A short hop was made on 24 August during high-speed taxi tests, followed by full flight on 27 August, the first aircraft to fly solely under jet power. Testing continued and in November the aircraft was demonstrated to RLM
Reich Air Ministry
thumb|300px|The Ministry of Aviation, December 1938The Ministry of Aviation was a government department during the period of Nazi Germany...

 officials in hopes of receiving funding for the development of a larger engine, but nothing seemed forthcoming.

Hans Mauch later told von Ohain the RLM was in fact extremely impressed, but he was concerned that Heinkel's airframe team did not have the knowledge to undertake engine development. Instead he and Helmut Schelp
Helmut Schelp
Helmut Schelp was the director of "advanced" engine development at the RLM's T-Amt technical division leading up to and during World War II. He used his office to fund a widespread program in jet engine development, which led to many of the engine concepts still used today...

 secretly visited a number of aircraft engine
Aircraft engine
An aircraft engine is the component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are almost always either lightweight piston engines or gas turbines...

 manufacturers to try to start programs there. Mauch left his position in 1939 leaving Schelp in command. Schelp was not as concerned about where development was taking place, and immediately started funding Heinkel to produce a more powerful engine.

Work on a larger version, the HeS 6, started immediately, and was tested under a Heinkel He 111
Heinkel He 111
The Heinkel He 111 was a German aircraft designed by Siegfried and Walter Günter in the early 1930s in violation of the Treaty of Versailles. Often described as a "Wolf in sheep's clothing", it masqueraded as a transport aircraft, but its purpose was to provide the Luftwaffe with a fast medium...

 late in 1939. While successful, notably in terms of vastly improved fuel economy, the weight was considered excessive and the design was abandoned in favour of the more advanced Heinkel HeS 8.

Specifications

For HeS 3b:
Dimensions: 1.48 m long, 0.93 m diameter
Weight: 360 kg
Thrust: 450 kgf
Kilogram-force
A kilogram-force , or kilopond , is a gravitational metric unit of force. It is equal to the magnitude of the force exerted by one kilogram of mass in a gravitational field...

 (4.4 kN) @ 13,000 rpm and 800 km/h
Compression ratio
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...

: 2.8:1
Specific fuel consumption
Specific fuel consumption
Thrust specific fuel consumption or sometimes simply specific fuel consumption, SFC, is an engineering term that is used to describe the fuel efficiency of an engine design with respect to thrust output...

: 2.16 gal/(lb·h) [18.0 L/(kg·h)]


For HeS 6:
Weight: 420 kg
Thrust: 550 kgf (5.4 kN) @ 13,300 rpm and 800 km/h
Specific fuel consumption
Specific fuel consumption
Thrust specific fuel consumption or sometimes simply specific fuel consumption, SFC, is an engineering term that is used to describe the fuel efficiency of an engine design with respect to thrust output...

: 1.6 gal/(lb·h) [13.4 L/(kg·h)]

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK