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744: CLB1/2 thrust wash-out at what alt or FL ?

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I thought I had been under the impression that CLB1 and CLB2 thrust washed out to full CLB thrust by 15,000' but am not sure if this is happening. It seems to have happened on certain flights but not on others. I am not sure if the inconsistency is user error or inadvertent user input--such as changing the target ALT on the way up.Appreciate any clarification or guidance here, thanks!Jonathan

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OK, thanks, I just tried a D-TO and CLB 2 and the N1 display worked BOEING textbook to 15,000'. I then repeated and at 12,000' during the climb while in CLB2, hit the CLB2 LSK in the THR LIM page and N1 dropped from 99% (which it had risen to from 92% earlier in the flight) to 95.5% and stayed at that level through 15,000' and above. So, it seems to me that if you intervene in the derated CLB thrust mode, the N1 resets itself instantly to some slightly lower level. Depending on the altitude at which one intervenes thus, N1 might just remain at a lower leve or it might continue rising but more slowly than in pre-programmed mode. I think this is where I've been getting confused previously, sometimes intervening with other thrust settings such as CLB1 or CLB --and the THR button on the MCP--and flipping around during the climb below 15,000 feet so that the pre-programmed washout never happened.I s'poze the rule is: when "the magic" is at work, do not intervene !Thanks for posting.Jonathan

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