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Captain_BH
7th Jul 2011, 02:59
Hi Guys,

Any smart guy could tell me how to use the Thrust R A T I N G S - Graph in Fcom 3.05.06 Page 3, And could you also tell me about the COrner Point how to know if its < or > than OAT !?!?


Thanks Guys

rudderrudderrat
8th Jul 2011, 07:05
Hi Captain_BH,

I'm not that smart - but in the example they give, it shows how to estimate the N1 Flex is about 85 and a bit %. (50C Flex, P Alt 2,000 ft and OAT = -10C)

If you look in the top right hand corner (Corner Point), they have drawn a graph showing flat rating temp v P ALT curve. At a Pressure Alt of 2,000 ft, the curve is intercepted at 40 degs C.

In this particular example, since the OAT < than the "Corner Point" value (Flat rating Temperature) then no correction is required.

http://www.merrowresidents.org/pprune/Cornerpoint.jpg

Captain_BH
27th Jul 2011, 18:09
well, you are smart!

THank you very much bro..