Quote:
Originally Posted by palidian
The ME262 over heats at 100%, jet engines generally do not get hot (so to speak, at least not to start melting things.) due to there nature.
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Well you do need to monitor engine gas temperature, that just goes without saying.
As far as the unreliability of the Jumo's in general one key factor is low quality steel ...
http://www.stormbirds.com/project/te...echnical_3.htm
JUMO The Junkers Jumo 004 is often remembered as a temperamental and failure-prone powerplant. Despite its advanced design, engine life was only between 10 and 25 hours, with the mean being at the lower end of this range. These failures were anticipated to some extent and the Me 262 was designed to permit extremely rapid engine changes.
Contrary to popular belief, the 004A was a fairly sound performer when premium steels were used, and early versions were known to achieve a 200-250 hour service life. However, the diversion of critical materials into U-boat production and other projects late in the war forced Junkers to produce the 004B model with only 1/3 of the high grade steel that had been used in the 004A. It was to be a disastrous concession for the Me 262.
The introduction of inferior metals compounded an already problematic situation with the turbine blade design. These blades were rigidly mounted, contributing to severe root stress relief problems. The weaker metals simply could not withstand this kind of abuse and regular compressor failures were an inevitable consequence.
Also remember that because the Jumo's are axial flow with FIXED geometry compressor blades they are also HIGHLY susceptible to compressor stall and surging with all the inherent problems (such as randomly shedding blades) that brings with it. These engines are nothing like the modern turboprops you may be used to working on or have studied.
Translated ME262 Pilots handbook:
http://www.zenoswarbirdvideos.com/Im...otHandbook.pdf