Inventing of the turbojet engine

[Dronescapes]

A documentary about Whittle's invention (patented in1930). The video also features interviews with Hans von Ohain, Whittle's German counterpart, credited with the first flight of a turbojet.
It is interesting to note that Whittle's research in those years was largely unsupported, whereas von Ohain had every resource needed at his disposal. What would have happened if Whittle's project had been approved and supported by the Air Ministry when it was presented in 1929? After all, Whittle's engine powered the MiG-15 in the 50s, courtesy of Rolls Royce's 'gift' to the Soviets.

View: https://youtu.be/G0T4-XG612Q

 

[GrauGeist]

Whittle didn't "invent" the turbojet engine, he developed and built his centrifugal design.

The first aircraft axial jet design was patented by Maxime Guillaume in the early 20's and Britain's first axial jet engine, the Vickers F.2, was designed by Alan Griffith, who published the design in 1926.

 

[Dronescapes]

Whittle didn't "invent" the turbojet engine, he developed and built his centrifugal design.

The first aircraft axial jet design was patented by Maxime Guillaume in the early 20's and Britain's first axial jet engine, the Vickers F.2, was designed by Alan Griffith, who published the design in 1926.

Interestingly Griffith was the one that turned down Whittle's proposal in 1929...No conflict of interest there. Had Britain developed Whittle's engine starting 1929 (therefore before he patented it in 1930), they would have had a reliable engine, especially if you consider that despite little funding and little support, Whittle managed to test his engine on the ground in 1937. that's before von Ohain's first flight. The Vickers F.2 flew, I think, in late 1943, that's 6 years after Whittle's test. How good was Whittle's engine? Considering that the Soviets used it in the 50s in their MiG-15, courtesy of Rolls Royce, I would say it would have been a pretty good jet engine at the beginning of the conflict, hadn't Griffith dismissed it in 1929. Also, let's not forget that von Ohain had all the support and funds needed and that his 1939 engine was anything but good. It took Germany many more years to have a decent one, but still unreliable, and by then it was useless anyway. Whittle's engine was less performing, but a lot easier to develop into a good engine, and it's hard to deny it would have made a difference in the late 30s. It's also interesting what von Ohain himself says about the race for the jet engine:

"The first patent of a turbojet engine, which was later developed and produced, was that of Frank Whittle, now Sir Frank. His patent was applied for in January 1930. This patent shows a multistage, axial-flow compressor followed by a radial compressor stage, a combustor, an axial-flow turbine driving the compressor, and an exhaust nozzle. Such configurations are still used today..." and "From the beginning of his jet propulsion activities, Frank Whittle had been seeking means for improving the propulsive efficiency of turbojet engines. He conceived novel ideas for which he filed a patent application in 1936, which can be called a bypass engine or turbofan.

To avoid a complete new design, Whittle sought an interim solution that could be merely "tacked on" to a jet engine. This configuration was later known as the aft fan. Whittle's work on fan jets or bypass engines and aft fans was way ahead of his time. It was of greatest importance for the future or turbo-propulsion." and "In April 1937, Whittle had his bench-test jet engine ready for the first test run. It ran excellently; however, it ran out of control because liquid fuel had collected inside the engine and started to vaporize as the engine became hot, thereby adding uncontrolled fuel quantities to the combustion process. The problem was easily overcome. This first test run was the world's first run of a bench-test jet engine operating with liquid fuel."

Ohain said that he had not read Whittle's patent, and Whittle believed him.
However, the Whittle patent was in German libraries, and Whittle's son had suspicions that Ohain had read or heard of it.
Years later, it was admitted by von Ohain in his biography that this was so. Author Margaret Conner states ″Ohain's patent attorney happened upon a Whittle patent in the years that the von Ohain patents were being formulated". Von Ohain himself is quoted as saying "We felt that it looked like a patent of an idea" "We thought that it was not seriously being worked on." As Ohain's patent was not filed until 1935, this admission clearly shows that he had read Whittle's patent and had even critiqued it in some detail prior to filing his own patent and some 2 years before his own engine ran.

 

[GrauGeist]

Griffith's designed axial jet engine, the Vickers F.2 was successfully first run in 1941.

Keep in mind that Whittle's design was not a prior patented true Axial design, but a centrifugal modified Axial design.

His patent for a centrifugal design may have been first for it's type, but not the first.

 

[ThomasP]

So, the Vickers F.2 was only ~4 years behind Whittle's for first run?

 

[pbehn]

I read years ago that Whittles early research was into a "jet" where the compressor was driven by an engine. He calculated that you could run the compressor off the exhaust to have a sustainable combustion that produced a surplus that could be used as thrust. I presume that there are patents for jet engines of this type,

 

[SaparotRob]

Wasn't that the system the first Italian jet used?

 

[GrauGeist]

So, the Vickers F.2 was only ~4 years behind Whittle's for first run?

Whittle and Von Ohain's engines were Centrifugal flow where as the Vickers F.2, Jumo004 and BMW003 were Axial flow.

Different design theories.

 

[GrauGeist]

Wasn't that the system the first Italian jet used?

Yes, the Campini N.1 motorjet, which first flew in 1940, about a year after the He178.

 

[pbehn]

Wasn't that the system the first Italian jet used?

It just posted that to illustrate that there were ll sorts of ideas and patents. From the piece I read Whittle had trouble getting backing because it was all about calculations and theories, and as was illustrated later many of these were wrong to start with. I suppose at the time a jet engine as we know it now would seem like a perpetual motion theory to those who believed in motor jets.

 

[z42]

It just posted that to illustrate that there were ll sorts of ideas and patents. From the piece I read Whittle had trouble getting backing because it was all about calculations and theories, and as was illustrated later many of these were wrong to start with. I suppose at the time a jet engine as we know it now would seem like a perpetual motion theory to those who believed in motor jets.

It's easy in retrospect to say that the state should have poured massive resources into jets starting in the early 1930'ies, and if so, the WW2 air war might have looked very different. But heck, the RAF was introducing a new biplane fighter as late as 1937 (Gloster Gladiator). In 1929 it wouldn't be entirely unreasonable to view jet engines as yet another crackpot theory. Or if not outright a crackpot theory, an entirely wild concept that most likely wouldn't work at all, and even if it did, nothing with a useful application.

 

[GrauGeist]

Even the He178 got a collective yawn from the RLM when it was demonstrated.
And again, the RLM lacked any real interest in the He280 when it was demonstrated almost two years later.

 

[pbehn]

It's easy in retrospect to say that the state should have poured massive resources into jets starting in the early 1930'ies, and if so, the WW2 air war might have looked very different. But heck, the RAF was introducing a new biplane fighter as late as 1937 (Gloster Gladiator). In 1929 it wouldn't be entirely unreasonable to view jet engines as yet another crackpot theory. Or if not outright a crackpot theory, an entirely wild concept that most likely wouldn't work at all, and even if it did, nothing with a useful application.

Many things are of their time. If you were to hand the detailed plans and all technical info for a Whittle or RR jet to the Wright Brothers how much would it have advanced aviation?

 

[ThomasP]

re "Whittle and Von Ohain's engines were Centrifugal flow where as the Vickers F.2, Jumo004 and BMW003 were Axial flow.

Different design theories."

I know, just teasing as I know your interest in the F.2

 

[GrauGeist]

re "Whittle and Von Ohain's engines were Centrifugal flow where as the Vickers F.2, Jumo004 and BMW003 were Axial flow.

Different design theories."

I know, just teasing as I know your interest in the F.2

To be honest, I'm a fan of the Hirth engines - but in all honesty, had Griffith's design been pursued at the time, Britain may have had an Axial flow jet well before the war.

On the same token, had the RLM realized what they were looking at in 1939 and placed a priority on the jet program at that point in time, the air war over Europe would have been quite different.