50th Anniversary of First Jet Engine Flight

It had limped to within a few yards of the drive before it expired – on a Saturday afternoon, just after the dealer’s service department closed for the weekend. Dr Hans Joachim Pabst van Ohain, the man who invented the turbojet, the aircraft engine that changed the history of modern aviation, looked at the defunct V6, shook his head and gently closed the hood. “They’re so inefficient – car engines – that’s why I could never be bothered learning much about them. Hanny will be furious with me!”, he laughed.

Hans van Ohain is seventy seven this year but he still has a surgically sharp intellect, an impish sense of humour and a heart as big as the sky. It’s truly remarkable to find those traits in a man who can claim that he changed the history of the world and touched the lives of literally billions of air travellers and the pilots who fly for them.

August 27, 1939 began with low, stratified mists hanging in the still arr over Rostock, Germany. The city is near the Baltic coast in

what is now East Germany. A hint of the end of the golden weather was in the air that morning. In an off-limits hangar that was part of the Ernst Heinke!, A G Rostock plant, test pilot Erich Warsitz slid into the cockpit of the He 178. When the ladder was trundled away the odd little ancestor of all jet aircraft stood ready for its first history shattering flight. The He 178 was a conventional, shoulder wing monoplane with a moderate dihedral to its mostly wooden wings. They had an equi-taper planform and large trailing edge flaps inboard, beside the monocoque aluminium fuselage. It stood on modified tail dragging landing gear with its tail held almost horizontal by the rear wheel. And that, plus the absence of a propeller, is what made the He 178 so revolutionary. Inside the fuselage, in line with the wing’s trailing edge, sat the Hes 38, the van Ohain designed turbojet engine. It hadn’t been easy to bring all the bits and pieces together for the first test flight.

Hans van Ohain first began working on the turbojet at the age of 21 while working on his PhD in physics and Applied Mechanics at Gottingen University.

His first flight in an airliner had triggered the idea. He expected to float effortlessly through the sky from one place to another. Instead he found himself choking on fumes and deafened by the roar of the engines and the props. Hans as a physicist, theorized that a turbocharger with the piston engine removed and a steady there flow substituted in its place could produce thrust.

Hrs first prototype was set up on a test stand in the Physics Department courtyard at his university. The test engine was to be started with hydrogen and run on gasoline. The test aborted suddenly when the gas was pumped into the prototype and the resulting sheet of flame almost torched the university!

Scorched, but convinced that he was right, Hans went back to hrs drawing board. Hans’ professor also thought he was onto a revolutionary engine and recommended Hans to Ernst Heinke! a sort of Teutonic Howard Hughes, mad for speed and always eager to get the drop on the competition. Heinke! Underwrote Hans’ next efforts to prove the jet engine principle. Hans set up a design team of himself, a mechanic, an engineer and two draftsmen and built a more advanced prototype turbojet at the Marrenehe Plant. Perhaps Heinke! was security conscious or perhaps he’d been warned by Hans’ professor but the team was given a small work shop well away from the main plant on the outer edges of the aerodrome.

In the shed, late one night in March, 1937, Hans and his two assistants, Max Hahn and Wilhelm Gundermann, succeeded in proving van steady thermo flow concept with a hydrogen test engine. (No one was sure that the engine would run on rts own so Max Hahn’s task during the starting sequence was to stand by the jury rigged starter with a stout stick. At the first sign of the engine self destructing, Max was instructed to whack the leather starting belt off the turbine drive pulley. Fortunately the engine ran on internal power, was fully controllable and there off the leather starting belt by itself. )

The first flight engine of the HeS 38 was the result of a lot of frenetic design work by the small Ohain team. The HeS 1 was powered by hydrogen gas and the flight engine had to be able to use liquid fuel (gasoline). There were headaches aplenty with combuster development and even the HeS 3A was run to destrction before Hans was able to produce the Hes 38, which was fitted to the Heinke! He 178.

The pioneering airframe for the first turbojet flight was the design of the Siegfried and Walter Guenther brothers who were Heinkel’s top aerodynamic designers. The first sketches were begun in 1937 and the aircraft was so successful that it was airborne in short hops during taxiing testing on the Marienehe runway.

Motion pictures of the first flight show a large four door sedan almost as big as the He 178 towing the aircraft to the runway. Warsitz sat in the experimental jet with the canopy removed.

Hans van Ohain recalled that the day improved slightly but considerable stratified mist persisted as Warsitz started the jet engine (this time without the leather belt and the man with a stick!). Then, with the canopy fitted and latched, Warsitz began the takeoff roll for the flight that began modern aviation, as we know it.

The major flaw in the ten minute test hop was that Erich Warsitz couldn’t get the landing gear to retract. This forced him to keep the speed below 300km/hr. Han$ van Ohain thinks the He 178 in a ‘clean’ configuration was capable of about 800km/hr, given the 500kg (1,100lbs) of thrust produced by the Hes 38.

And even on its first flight the jet proved vulnerable to bird strike! Hans recalled that a large number of plovers lived in the grasses at Marienehe Aerodrome and they caused everyone in the design team considerable anxiety during the takeoff and landing. One small bird had been ingested by a test engine slung under a HeinkeI He 118,. according to Hans van Ohain, but the engine was undamaged by the unexpected ‘meal’.

Erich Warsitz was out of sight for some time due to the met conditions at Marienehe but then reappeared on final approach and made a smooth three point landing. Some reports claimed that the engine ingested a bird on the crosswind leg of the approach and Warsitz had to make a dead stick landing. Han van Ohain denies this since the jet taxied up to where Heinke! and van Ohain’s team were waiting.

Ernst Heinke! was a pragmatist, even with his exciting new and successful prototype. He allowed the necessary post flight checks but then ordered Hans and the others to leave the aircraft and the engine alone. Hans said he had reasoned that the He 178 had flown successfully once and should be able to do so again if it was left untouched. He wanted to repeat his success for the German Air Ministry, the men who issued contracts for combat aircraft.

The He 178 did fly again in November, 1939. Then the Cessna sized experimental aircraft went to the Berlin museum of technology, where it (and the HeS3B engine) disappeared under a stick of allied bombs late in WW II. Meanwhile, Dr Hans van Ohain was recruited to come to the USA after the war where he worked at Wright-Patterson AFB in Dayton, Ohio where he contributed 19 more jet propulsion patents to the USAF collection over the years.

Two years after the first flight of the He 178, in England, the Gloster 28/39, powered by the Whittle W1X became the fourth aircraft to fly using jet propulsion and the first English jet powered aircraft. Knowledge gained from this aircraft led directly tb the Gloster Meteor which fought with the RAF in the final year of the war.

Presumably because Dr Hans van Ohain was on the losing side and because Sir Frank Whittle was so close behind him, Hans has never been recognised as the ‘Father of the Jet Engine’. At time of writing nothing is unfortunately planned to celebrate the 50th Anniversary of Jet flight.

And that’s a bit sad, really. America’s, and the world’s, aerospace industries owe a lot to the early jet pioneers. But the lion’s share of the kudos has gone to Whittle, the man who happily admits he was the fourth one to get a jet aircraft into the air.

The principle of fair play and first pass the post seems to have been forgotten for Hans van Ohain. August 27, 1989 looks likely to pass unnoticed. That’s sad treatment for the man who made modern aviation’s greatest breakthrough.