World War Two Jet Engine Life

Hi, I tried to search through the archive, but really hard to find information.

The jet engine used on Me 262 was around 25(early time) to 45~50 hours(late time). How about those jet engine used by UK and USA in their warly jet fighter ? I assume they have better life time, but how good of them ? Couple hundred hours between change ?

Except the alloy, is there any other design feature or just because the manufacture capability made the jet engines used by UK and USA better ?

Thanks. If there is any articles or books you would like to suggest, thanks in advanced.

Mostly lack of cobalt and manganese to make high-temp steel alloys. However, with a largely foreign or even slave labour work force, even in aviation, quality control suffered. This affected more than jet engines. It belies the notion that if only Hitler had the foresight to immediately put the Me262 into production that it'd have reversed the course of the war. Certainly the new jets (what few could actually roll off the assembly lines anyway) could defend vital targets but they could do little to prevent the general mayhem wrought by Allied airpower. And due to short range and very short operational engine cycles, the Me262 would've been useless in the tactical support role, since it'd have zilch for loiter time and have to be stationed so close to the front that it'd be extremely vulernable to counterstrikes. I've seen some descriptions of rather advanced German designs for both fighters and bombers, many of which influence can be seen even today. However, to be able to actually produce these designs in sufficient quantity would've required time (which was running out), and raw materials, which would've necessiated either peace with either opponent or winning the war outright, since raw materials were the chief problem. And had Germany either defeated the Soviet Union or at least gotten the UK and the USA to agree to peace terms, the other would've likely quit anyway rather than take on the Third Reich alone. A simple case of the problem already being solved. The idea of a 'Jet Age' Luftwaffe is intruiging but belongs to an alternative history discussion. Also, it should be considered that the UK also had the Meteor at almost the same time as the Me262, though it was not the equal. Neither was the Bell XP-59 (The P-80 was undergoing trials by VJ-day). But both Brits and Yanks were learning quickly. The Rolls Royce Ghost engine was superior to the German Jumo 004. Had both the Me262 and the Arado 234 (which is not unlike the successful Canberra) been deployed earlier and in greater quantities than they were, it could be expected that sure, there'd be a brief interregum where Allied strategic bombing operations were imperiled (mostly daytime IMHO, the jets didn't seem to be practical as night fighters yet), but soon Allied jets would've appeared to challenge.

The figures I recall were 10 hours for the Me 262 as opposed to 25 hours for the Bell P-59A. I'm sure that in both cases the TBO was rapidly increased.

I wrote a piece for Air & Space that touched on this subject, 'Gentlemen, I Give You the Whittle Engine'; it appeared I think in 1992, the 50th anniversary of the P-59A's first flight. Alas, that was before articles were digitalized. I will scan it when I have an opportunity.

all the best

You might have a lok at this; Anselm Franz who designed the Jumo 004 of the Me 262 also designed the engine of the M1 Abrahams tank and the UH-1 Iroquis Helicopter after he immigrated into the US.
http://www.memagazine.org/backissues/september97/ features/franz/franz...

There were a number of factors; primarily was the fact that the Germans were short of Nickel and Chromium. When the Prototypes of the Junkers Jumo 004A came out that powered the Me262 the turbines, combustion chambers and exhaust nozzle was out of pure nickel chromium alloy.

The Production Jumo 004B engines had: 1 Austinitic Steel (Stainless Steel) Air cooled Stainless steal blades ionstead of solid refractory alloy blades. These didn't last long.

Changing the material also changed resonance and the Germans had to redesign the engine and run the spools at 8700 rpm instead or 9000. (they used musicians to pick the harmonics)

2 Combstion Chamber of Aluminuim Oxide Coated mild Steel. this was prone to burning through.

3 The translating exhaust cone nozzel was also of steel and distended and fell of sometimes blocking the exhaust and causing a flame out.

British engines didn't have the refractry alloy problem to deal with. Additionaly although the first German engines used centrfugal compressors they concentrated on axial flow types for the Me 262 because of a perceived superiority in efficiency and lower frontal area. Such compressors are more prone to surging and choking and require more sophisticated control or gentle throttle handling and it took the Germans a while to perfect these control systems.

For some resason the Germans also used a 10hp two stroke to start their engines, this was a pain to opperate (even thoiugh it had their own elctic starters) compared to the british all electrics. I don't know why; perhaps it was to do with Lead or Battery production? I note that the Fw190 had its electric control repaced by hydraulics as the war progressed and that the Germans always had a inertia flywheel starter crank on the Me109 to spare the battery/

I think it is fair to say that material shortages not ingenuity delayed the German Jets.