Jet - The story of jet propulsion: The inventors The aircraft The companies

Table of contents

1 Introduction

2 The Inventors

2.1 The Jet Engine

2.2 The first gas turbine of Aegidius Elling

2.3 The first jet engine ideas

2.4 The first jet flight by Henri Coanda

2.5 The patent of Maxime Guillaume

2.6 The Stern Report

2.7 The turbine bible of Aurel Stodola

2.8 Alan Arnold Griffith

2.9 Frank Whittle

2.10 Alf Lysholm from Milo

2.11 Herbert Wagner and Max Adolf Müller

2.12 Hans Joachim Pabst von Ohain

2.13 Helmut Schelp and Hans Mauch

2.14 On the way to series production

2.15 BMW in München

2.16 Bramo and BMW

2.17 Junkers in Dessau

2.18 Daimler-Benz in Stuttgart

2.19 Heinkel He S 011

3 The civil jet aircraft

3.1 The first generation

3.2 The second generation

3.3 The three big jets

4 The engine companies

4.1 Rolls-Royce

4.2 General Electric

4.3 Pratt&Whitney

4.4 CFM International

4.5 International Aero Engines

4.6 BMW Rolls-Royce

4.7 Engine Alliance

5 Image Sources, Thanks

1 Introduction

This book tells the story of the development of jet propulsion, from the first ideas over the first flight of a turbojet engine on 27 August 1939 up to the present time, from the Heinkel He 178 aircraft with the Heinkel He S 3 B engine up to the Airbus A380 with the Trent 900 turbofan.

I have pursued this subject over decades. After my studies of aircraft and engine technology at the Technical University TUB in Berlin 1963-1969 I started to work in the propulsion department of VFW in Bremen, later named MBB, DA and finally Airbus Bremen. For 36 years I have studied, calculated and evaluated turbojet engines. I have participated as engine expert in nearly all projects and programs of my company, I have worked for the VFW 614, all Airbus models including the A380, the MPC75 hundred-seater, the European Supersonic Commercial Transport ESCT and the military A400M.

My archive of reports, informations and photos had reached over the years a respectable size and looking at it I had the idea to write a book.

But that turned out to be more difficult and time consuming than I initially thought. As first chapter I chose the inventors, because I had been lucky to attend the symposium 50 Jahre Turbostrahlflug (50 years of turbojet flight) in München on 26/27 August 1989. On this occasion I got to see among other celebrities the German inventors Hans von Ohain and Anselm Franz. The English inventor Frank Whittle unfortunately could not come. When I started then in 2007 with the deeper study of these gentlemen, they had already passed away and I had to turn with questions, that inevitably arose, to other sources. A great help was Dr.Volker Koos from Rostock, who had already written some books about Ernst Heinkel, his aircraft and engines. With his help I got contact to the family of Hans von Ohain, his son-in-law and to his former best friend. And then it was a great stroke of luck, that in 2008 the son of Frank Whittle gave a lecture in Hamburg about his father and Hans von Ohain.The exchange of informations with all the mentioned persons resulted in an extensive collection of data about the story of the inventors and their inventions.

The content of this book is based on three sources:

My expertise after 36 years of work on the subject

The knowledge of experts and witnesses

The study of publications, brochures, books and online material

The book is not complete. Who ever looked into the „Jane‘s Aero Engines or into the „World Encyclopedia of Aero Engines, will know that the number of built turbojet engines reaches some hundred and must be muliplied by 3 or 5 by the number of variants. My choice can therefore only be a selection. I left out the Russians, for various reasons, and have concentrated only on the important engines and companies of the West. As far as I know, never before have all the great engine companies and their engines been mentioned together in one book. One exception are the big books of Bill Gunston, which are pure encyclopedias without historical background.

I have also left out all Airbus models. About these aircraft there exist so many books, that I could not contribute anything new. But the engines of the Airbus models are all covered in the appropriate engine company chapter.

For each mentioned engine I have made a box of characteristics with the important informations and with a photo. As most engines stem from the English speaking world, I chose the thrust in pound (lb). With one exeption. The dimension Kilopond (kp) and Tonne (to) were common in Germany long time ago, but were given up in the modern world. In the story of the German engines before 1945 there was only the (kp) and here I made an exception and have used the English (lb) and the German (kp).

Concerning numerical values one has to be cautious. Who looks through 10 sources might find 5 or more different values for a date, a thrust or another parameter. Here one has to compare, to evaluate, to find the most reliable value. Even in the internet not all values are consistent. In technical developments the time plays a role. The takeoff weight of an aircraft changes in the design phase every month or every half year and is later in the service depending on other factors.

For all aircraft and engines being built or used in the presence I have tried to find the status of 2022. That year was not any more part of my work, which ended 2005, so I had to use informations from the internet, which change permanently. I have tried to avoid big formulas, but I have produced plots, a graphic can say more than many words.

I wish the inclined reader an entertaining reading pleasure. My goal would be achieved if the reader occasionally thinks: where did he get that from, or: I didn't know that before, or: he explained that well. After my lecture on Hans von Ohain on 27 August 2009 in Rostock, a lady approached me and said: Now I understand how an engine works. I was a little happy and a little proud.

About this book I am also a little happy and a little proud.

Wolfgang Brix

January 2023

2 The Inventors

2.1 The Jet engine

The simplest jet engine is the balloon, well known to all children. When it is blown up and let loose, it flies away, driven by a (certainly small) force, which arises from the air leaving the balloon through the nozzle, the hole by which it was blown up. The thrust is calculated :

Gross thrust = mass flow x jet velocity

Net thrust = gross thrust – inlet momentum

In the special case of the balloon there is no inlet momentum (as for the rocket engine) and it follows :

Net thrust = gross thrust = mass flow x jet velocity

Soon it becomes obvious, that this jet engine is not working for long, the balloon is landing after some seconds in the corner of the room. The reason is evident: the amount of air in the balloon decreases continuously, the pressure decreases continuously and when the balloon is empty, the thrust comes down to zero.

At this point the jet engines are split into two main groups, into the rocket engines, which like the balloon carry the medium of thrust production in their interior and consume it until it is empty. In the rocket this is called burnout. The second group gets fresh supply from the air, in which the aircraft flies. The same amount of air that is producing thrust in the nozzle is refilled in the inlet of the engine.

At high flight velocities, above the speed of sound (Mach=1) the incoming air has sufficient high pressure from the ram effect to keep the engine running and producing thrust. These ram jets do not need any mechanical compressors, the ram has taken this task.

At small flight speeds the ram produces a too small pressure, at take off the ram is zero. If one intends to make the engine running for a longer time, one has to refill the air in the balloon or the engine at the same speed and the same pressure. To do that one needs a machine that produces a defined amount of air at a defined pressure, which is called a compressor. And this compressor needs a powerunit, the energy for the compressor must be generated.

So the task is clearly defined: for a jet engine for takeoff and subsonic speeds one needs a compressor and a power unit to drive the compressor and a nozzle that accelerates the compressed air to the nozzle velocity, producing with mass flow and nozzle jet velocity the gross thrust.

2.2 The first gas turbine of Aegidius Elling

For the propulsion of a compressor a machine is needed, that produces mechanic power and delivers it via a shaft to the compressor. Two such machines are available. The first one is the piston engine, the second one is the turbine, which can be run with any medium, water, steam or air. When the compressor is run with air, the turbine is also running with air, then it is a gas turbine

The different jet engine types

The ram jet for speeds over Mach = 1

The turbojet engine with a turbine as propulsion for the compressor

The motor jet engine uses a piston engine as propulsion for the compressor

The schematic pictures above stem from Helmut Schelp, member of the RLM (Reichsluftfahrt ministerium 1940).

In 1900 the folowing power machines are known:

The piston engine

The steam turbine

The gasturbine is not yet invented at this time. But soon it is not only invented, but it is built.

In 1903 a Norwegian makes the first contribution on the way to the turbojet engine, he contributes the word „turbo", the turbine. His name is Aegidius Elling, he is is born 1861 in Oslo and works after his studies at the Christina Technicum 1881 mainly on the field of ship steam turbines in Sweden and Norway. Already in 1884 his first gas turbine patent is registered, but it is not functioning, what he frankly confesses. The next 19 years lie in the dark, but then comes his great day: on 27 June 1903 Aegidius Elling writes into his diary:

„I have made the world‘s first gas turbine which has given positive (excess) power"

Aegidius Elling (1861-1949)

On the left photo one can see the gas turbine of Elling, as it is shown in the Norwegian Technik Museum in Oslo. In the middle it shows the radial turbine and on the left and right 6 radial compressors.

This work of Aegidius Elling is unknown outside of Norway. In the 60s Prof. Dag Johnson writes an article (in Norwegian) about Elling and sends it to Frank Whittle (s. chapter 2.9). When an English version is available, Whittle writes back:

„…I have read the account of Aegidius Eling’s work with great interest and am very impressed by the extent by which he anticipated later events. My impression is that if materials and aerodynamic knowledge which became available to me had been available to Elling the gas turbine would have been with us some 20-30 years earlier than it was. Unhappily he had the misfortune to be many years before his time – as so often happens with major innovations.

Yours sincerely Whittle"

The first turbojet engine first ran at the beginning of 1937, 34 years after Elling’s successful gas turbine run.

2.3 The first jet engine ideas

The very first ideas to solve the task to design a jet engine are certainly lying in the dark of history. Short before 1910 the first proposals appear in the form of articles in special papers or in the form of patent applications. Several Frenchmen are beginning.

In 1908 René Lorin applies for a patent that shows a piston engine that produces thrust by leading the exhaust gases into long nozzles. When the suction of air is done again through the long nozzles, then the flow is an oscillating to-and-fro flow and the question is, whether this produces a thrust.

In 1909 M.Georges Marconnet apllies for a patent which shows several solutions.The Fig.1 shows an engine with inlet 2, compressor 1 and burner 4, the heated pressure air is passing a chamber 6 and goes into a nozzle 8 to produce thrust.The Fig.2 shows a similiar design, where the heated pressure air is splitted by a turning wheel into seperate streams which flow through channels 10 and 11 into the nozzle. The propulsion of the compressor and the wheel is not shown in this sketch.

In 1913 the above mentioned René Lorin continues to work on the idea of a jet engine and applies for a patent of new ideas. In Fig.8 and 10 he shows ram jets with differing nozzles, whereas in Fig. 7 and 9 blowers G do the compression of air. Again it is not visible how these blowers are driven. The proposals are again incomplete and rather sketchy.

2.4 The first jet flight by Henri Coanda

In 1910 a name appears, that is well known today in the world of aviation, but was totally unknown at that time. Also the country from which he is coming has nothing to do with aircraft. The man is Henri Coanda and he comes from Rumania. On the Aviation Exposition 1910 in Paris he presents a complete aircraft that amazes the expert world because it has no propeller.

Coandas flight apparatus is a doubledecker with an extreme slender fuselage and a motor without propeller.

The poster of the exhibition underlines this novum: Seuls Aeroplanes sans Hélices means: only airplanes without propeller. A photo from the days of the exhibition shows in the background the aircraft and on a platform a part of the motor. Dimly one can read: Turbine Propulsive 50 hp.

The poster

The motor

In May 1911 Coanda gets a patent in Switzerland for a propulsion (Propulseur) without propeller. It can be assumed, that this is the motor of his aircraft from 1910. It shows a radial compressor, which ejects the air sucked in from ahead (here from above) over an annular nozzle backward (here downward).

Henri Coanda (1886-1972)

This is the original report of Henri Coanda about his flight on 16 December 1910 :

It was on 16 December 1910. I had no intention of flying on that day. My plan was to check the operation of the engine on the ground but the heat of the jet blast coming back at me was greater than I expected and I was worried in case I set the aeroplane on fire. For this reason I concentrated on adjusting the jet and did not realize that the aircraft was rapidly gaining speed. Then I looked up and saw the walls of Paris approaching rapidly. There was no time to stop or turn round and I decided to try and fly instead. Unfortunately I had no experience of flying and was not used to the controls of the aeroplane. The aeroplane seemed to make a sudden steep climb and then landed with a bump. First the left wing hit the ground and then the aircraft crumpled up. I was not strapped in and so was fortunately thrown clear of the burning machine.

It is the first jet flight in the aviation history!

But not a turbojet flight, this will come on 27 August 1939!

2.5 The Patent of Maxime Guillaume

It is often cited, however only by expert historians: the patent No 534.801 of the Frenchman Maxime Guillaume, applied for on 3 May 1921 and granted on 13 January 1922 and published on 3 April 1922. It is entitled „Propulseur par réaction sur l’air", propulsion by reaction on air, which certainly means with reaction the force, that occurs after the old principle actio = reactio. This is the momentum principle.

Maxime Guillaume is born in 1888 in the region Le Berry in France. He studies general engineering at the national school of „Arts et Métiers (arts and trade) in Paris. Soon after his studies he writes his famous patent and then dedicates himself to agriculture and goes to Marocco and becomes director and inspector of the plantations in the region of Safi. In 1970 his book is published „The soil makes the climat (LE SOL FAIT LE CLIMAT). Twice he is honoured as chevalier. His date of death is not known.

The title of the patent

The only known photo of Maxime Guillaume

The figure in the patent shows clearly a gas turbine, consisting of a compressor, a combustor and a turbine. The components are described in detail :

1) Compressor and turbine are located on a common shaft

2) The stages of the compressor and the turbine are consisting of (turning) rotor blades and (standing) stator blades

3) In the combustor energy is introduced by the burning of kerosen

4) The combustor system consists of a pressurized fuel tank, a valve, a governor and pipes

5) Furthermore there is an electrical device with magnetic igniter

6) The starter consists of a hand driven crank turning the shaft over a gear, a free wheel clutch disconnects the crank at higher speeds

7) The shaft is supported at the ends by ball bearings in a housing

For a complete description of a functioning gas turbine one misses:

1) A description of the gas flow in front of the compressor (called inlet)

2) A description of the gas flow behind the turbine (called nozzle)

Maxime Guillaume takes it very easy to describe his patent: he states that his gas turbine produces a thrust, a propulsion force. He does not mention that this force must be in the direction of the