ferris
Sorry you did not like my analogy.
Try this one:
Most engines are rated for 5 minutes (10 minutes in case of an engine failure) at max thrust. Try this for every takeoff and the engines will run out of useful life at a much faster rate than a similar engine treated with TLC. Thermal and physical stresses are so much greater at max thrust compared with max continuous or Flex/De-rate. That is why there is the time limit.
I think your 1 minute is a little mean for a 13 hour sector at close to max takeoff weight. I am just guessing (and from experience) that the average sector length probably is less than 7 hours for a 744/340 so twice the number of applications of high thrust per day/year.
Returning to the humble motor car for a moment. Do you ALWAYS use full throttle when moving off, or would you normally use sufficient power for a slightly more sedate departure?
Recommended reading:-
http://www.smartcockpit.com/data/pdf..._and_Climb.pdf
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