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737NG CLB Thrust Limit.

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737NG CLB Thrust Limit.

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Old 27th Nov 2014, 16:47
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Question 737NG CLB Thrust Limit.

After receiving clearance for an unrestricted climb, is there a quick way to select full CLB thrust, without having to open the N1 page on the FMC?
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Old 27th Nov 2014, 17:35
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If you are below 2500 RA TOGA will give you full climb or you could select level change on MCP....

Personally speaking I always advice gentle climbs & doecents you would be surprised how much the pax appreciate it (assuming your big on customer service)
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Old 27th Nov 2014, 19:16
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or you could select level change on MCP
The above statement does not delete the reduced thrust, it will continue to use CLM-1 or CLM-2 if used for takeoff.

TOGA will remove the reduced thrust selection (as a 2nd TOGA press gives FULL thrust) but can only be done at low altitude as stated.

Once above that altitude, N1 page selection is the only option or wait until the aircraft is climbing higher and it automatically changes.
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Old 28th Nov 2014, 03:28
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Assuming you are in VNAV you could try Level change and then immediate back in to VNAV, I think that would delete the lesser climb thrust and Put the thrust mode in to AUTO....
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Old 28th Nov 2014, 04:49
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You could disconnect the A/T and firewall..
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Old 28th Nov 2014, 16:09
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Yes yes firewall it next time
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Old 29th Nov 2014, 01:26
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You cannot select full CLB thrust with less than 2 actions - and the quickest one is to reach for CDU: N1 LIMIT page -> CLB. Just don't forget to reset it to AUTO later on.

I have no idea why someone would need to do this VERY fast (faster than two buttons on CDU) though.
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Old 29th Nov 2014, 06:10
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We just always deleted CLB1/2 on the N1 page, that way it stays in AUTO and we get full climb thrust. Yup, it needs three clicks, but it isn't all that urgent, isn't it?
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Old 29th Nov 2014, 07:45
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Just firewall it and relax
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Old 29th Nov 2014, 07:50
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Push the two EEC buttons once. You need two fingers, but only one hand, and can be done at once. See how your climb performance improves.
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Old 29th Nov 2014, 08:51
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It is Christmas time after all. Don't mind seeing a little colour on the upper DU.

As mentioned two step action IS required to delete the r-clb setting. I would rather delete it at the bottom of the N1 page rather than select clb. The need to reset to auto just adds another step that I have to remember that I'd rather not have to.

And I think the quick part is lost in translation. I assume the OP intends to say most efficient.
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Old 30th Nov 2014, 22:34
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Angel

Now that all this discussion about Thrust Modes is up, how are you guys dealing with that bulletin regarding "eec software updates" that change the spool up/down time while at high altitudes ?

Here, is almost that a "common" SOP, to always select CON after reaching the cruise altitude.

Nevertheless, the bulletin says that this is only ONE of the methods that could help in case you get yourself trapped in such scenario (looooooong time to have an engine response after thrust decreased under 60% N1 etc etc).

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Old 30th Nov 2014, 23:54
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I always select 'CLB' when the trust limit changes to 'CRZ' at top of climb. The EK 777's were modified to stay in CLB at TOC, so even thought there is no difference in N1 between CON & CLB, CLB just looks right to me. (CON is for engine failure situations in my silly mind).

That being said, most of the F/O's I fly with have not read the bulletin & have no idea why I select it. Most eventually ask. From their comments, it seems that most captains haven't read the bulletin as well.

Some, after reading the bulletin when I pull it out to show them, point out that it is not a requirement, only a recommendation. While that is correct, I would rather stack things in my favour. And having seen how many do not pay close attention to airspeed in the cruise, particularly at high altitude, I would have thought that they would be keen for the extra thrust margin available with the auto throttle engaged.
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Old 1st Dec 2014, 04:43
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How does selecting another trust limit affects the spool-up time?
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Old 1st Dec 2014, 06:58
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How does selecting another trust limit affects the spool-up time?
It doesn't. Not going below 60%N1 does & that is one of the recommendations.

The higher thrust limit gives greater power to recover from a low speed condition with the auto throttle engaged.
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Old 1st Dec 2014, 07:51
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and so it begins......
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Old 1st Dec 2014, 16:21
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I find that holding the throttles from coming back manually does the trick....Agree that smoothness is a nicer way though, after all that's why you selected CLM-1 or CLM-2 anyway isn't it?
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