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Old 05-16-2012, 11:15 AM
lane lane is offline
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Join Date: Nov 2008
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Quote:
Originally Posted by 41Sqn_Banks View Post
I hope you guys are aware that the line "Emergency 5 mins.max." is related to "95°C" oil inlet temperature?



This test certificate has a better layout: http://www.spitfireperformance.com/k...ertificate.jpg

The power curve is a simplified form of this graph: http://forum.1cpublishing.eu/attachm...1&d=1337143252
and most certainly only contains calculated values which were derived from certain reference values or were applied shorty under controlled conditions to determine the engine power.
Good post 41Sqn_Banks,

I concur that "Emergency 5 mins.max." on the Inspection and Test Certificates is related to "95°C" oil inlet temperature.

Unfortunately I haven't seen a power curve for the Merlin III similar to the one you posted for another type. My understanding is that the power curve figures shown on the Inspection and Test Certificates were obtained through bench testing. In the case of N.3171 the engine Inspection and Test Certificate is dated 9-6-39 whilst N.3171's first flight occured on 10-11-39. The A.&.A.E.E. report on N.3171 notes:
"The engine installed in the aeroplane develops slightly less power under test bed conditions than that in K.9793, the aeroplane fitted with the 2-pitch airscrew. This could have the effect of reducing the top level speed by about 2 m.p.h. "
One can see that the power figures were not pulled from a chart given the differing powers obtained:
K.9703 Inspection and Test Certificate
N.3171 Inspection and Test Certificate