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They must have taken out both the compass and the cabin heater to do that.Keep in mind that the total miles flown was over 513 million miles.
Add to that each re-entry saw sustained temps of 3,000°F (1,648°C) as well as the stresses of launch: 0 to 18,000mph (28,968kph) in about 8 1/2 minutes.
The Jumo diesels, fuel injection and pressure-cooling, and other German innovations
And nose armor - don't forget the nose armor...They must have taken out both the compass and the cabin heater to do that.
design data is typically generated by companies trying sell a concept or get investments, which makes them the least of sources for comparison of performance, below even manufacturing estimates. Bench testing is far more reliable and procurement testing/flight testing the best. As such, as far as I can find in my research of "Turbojet History and Development, vol 1, Great Britain and Germany", Kay, Germany, in WWII, was never successful with any type of jet engine generating more than 2800 lbs thrust, this on a HeS 011 (and this was only for one hour). In comparison, the US company Westinghouse tested the all American developed , axial compressor, 24C (J34) at 3000 lbs/thrust in April, '45, Allison with a British helped centrifugal compressor design was starting production with the 4000 lb thrust J-33 in the beginning of 1945. in Britain, In early 1945, the 3000 lb thrust de Havilland Goblin II, although in reliability upgrades, was in production. By the end of 1944, the Rolls Royce Nene engine, which would be used in the mediocre F-9F Panther and the superb Mig 15 in the Korean War, was running at 5000 lbs/thrust. Because of the Nene engine's 5000 lb/thrust, I would have to select the British as the most advanced jet development. Soon the axial engines would eventually eclipse the centrifugal engines, but that was several years away.This may seem to give the overall "best" to the UK which is competitive in all categories without winning any of them! However since jets were THE technology of aircraft engines to come AFTER the war, and since we are talking design rather than performance or impact - then the real winner of this question is: Germany
The Allisons used glycol and didn't switch to a glycol water mixture until late in WWII. Glycol has a much higher boiling point than water.Callum Douglas did Online lecture on WW2 engine development on the German engines that showed that the German pressure cooling systems were late and prone to failure because of poor radiator designs that could not withstand the fairly low pressures used.
Allison probably used pressure cooling as early as 1938. The P-40 long nose aircraft had a maximum coolant temperature of 125C and I would expect that could only be obtained with pressurized cooling. The same temperature limit applies to the -89 engine which definitely had pressure cooling which supports this belief, but is not conclusive.
Incidentally Rolls Royce used Allison designed bearings.
I voted England, mainly for the Merlin.
In my view it was the most successful engine, running in 39 and developed until 45 with an incredible development. Other Countries had great engines, but the Merlin has powered everything and was always on top of performances.
The Merlin was awesome but BMW had a better fuel control - the single lever automatic control including prop. I have forgotten all the details but a Spitfire Pilot once commented on the pilot workload even after "Miss Shilling's orifice" had been deployed.
The Allisons used glycol and didn't switch to a glycol water mixture until late in WWII. Glycol has a much higher boiling point than water.
RR used the Allison manufacturing process but the bearings were of different materials.
"... a much higher boiling point" ..
at atmospheric pressure...
(Which it wasnt at.)
I agree in general terms but the Germans and Japanese were developing axial engines from day one as was Griffith in England. Unfortunately the German authorities were ignoring the jet engine, the Japanese (and Germans) had metallurgy problems and Britain ignored Griffith.design data is typically generated by companies trying sell a concept or get investments, which makes them the least of sources for comparison of performance, below even manufacturing estimates. Bench testing is far more reliable and procurement testing/flight testing the best. As such, as far as I can find in my research of "Turbojet History and Development, vol 1, Great Britain and Germany", Kay, Germany, in WWII, was never successful with any type of jet engine generating more than 2800 lbs thrust, this on a HeS 011 (and this was only for one hour). In comparison, the US company Westinghouse tested the all American developed , axial compressor, 24C (J34) at 3000 lbs/thrust in April, '45, Allison with a British helped centrifugal compressor design was starting production with the 4000 lb thrust J-33 in the beginning of 1945. in Britain, In early 1945, the 3000 lb thrust de Havilland Goblin II, although in reliability upgrades, was in production. By the end of 1944, the Rolls Royce Nene engine, which would be used in the mediocre F-9F Panther and the superb Mig 15 in the Korean War, was running at 5000 lbs/thrust. Because of the Nene engine's 5000 lb/thrust, I would have to select the British as the most advanced jet development. Soon the axial engines would eventually eclipse the centrifugal engines, but that was several years away.
I agree in general terms but the Germans and Japanese were developing axial engines from day one as was Griffith in England. Unfortunately the German authorities were ignoring the jet engine, the Japanese (and Germans) had metallurgy problems and Britain ignored Griffith.
GE had the benefit of many thousands of turbos so had a good background to draw on.
This very interesting period is expanded upon in a very good paper here, written by Frank Armstrong (former head of the British NGTE facility, onceBritain ignored Whittle for some time based on feedback from Griffith.
IIRC, Griffith's first axial turbine engine was to be a turboprop, and it was only after Whittle demonstrated a jet engine that Griffith moved to a jet engine program.
It always amazed me that people used something flammable for a combat planes coolant, what could possibly go wrong? Did they experiment with petrol?And Glycol has a lower heat transfer capacity.
Glycol 2.433 kJ/kg/°C
Water 4.184 kJ/kg/°C
It takes 70% more energy to raise water 1°C than for glycol.
Even in recent times - I worked with a Ximango motor glider that ran a liquid cooled Rotax engine. For a spell, they ran a flammable coolant!It always amazed me that people used something flammable for a combat planes coolant, what could possibly go wrong? Did they experiment with petrol?
Plus because Glycol has really low surface tension, it leaks like you woudlnt believe. I think by the time its about 50/50 with water its ok in that respect.Even in recent times - I worked with a Ximango motor glider that ran a liquid cooled Rotax engine. For a spell, they ran a flammable coolant!
View attachment 655042
It'll also spread like crazy on a shop floor.Plus because Glycol has really low surface tension, it leaks like you woudlnt believe. I think by the time its about 50/50 with water its ok in that respect.
I have always had the opinion that the Germans made an error by abandoning the centripetal compressor too soon. Each axial flow compressor stage and associated stator stage has to be designed to unique varied airflow parameters and made to work as compared to the much simpler centripetal compressor which has only one stage to design to. Had the Germans pursued the simpler design they may have had a very capable fighter a couple of years earlier and kept their cities clear of the upcoming bomber formations and escorts. Had the Germans installed more reliable 2500-3000 lb thrust engines in the Me 262 in Jan 1944, the outcome of the war could have been altered, certainly extended.I agree in general terms but the Germans and Japanese were developing axial engines from day one as was Griffith in England. Unfortunately the German authorities were ignoring the jet engine, the Japanese (and Germans) had metallurgy problems and Britain ignored Griffith.
GE had the benefit of many thousands of turbos so had a good background to draw on.
Britain ignored Griffith.
Now of course defunct (who cares about Science !), and I believe was about to be turned into a Waitrose car-park or somesuch newbuild junk.