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76 Wornout Rubber
Instead of being 'just another number' I could order a
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Join Date: Jan 2008
Location: Dubai
Posts: 8
Woodpecker,
The reason why 767s get colder fuel temperatures than 777s in the same enviroment, is that fuel temperatures are closely (but not exactly) related to the TAT and not the OAT. The higher speeds on the 777 keep the fuel warmer.
Fuels system engineer working on new jet a/c about 10 yrs ago told me wing thickness was important.
777's typically cruise 2-4000' higher on the same stage length. That temperature difference, below FL370 typically, is warmer for the 767.
You TAT theory can be tested. Fly the same altitude at increasing Mach speeds and note the temperature rise. I'll try it on my next flight. I'm guessing the difference will be very small.