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744 thrust reduction function?

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Is the FMC governed thrust reduction function still supposed to work even if one is not flying with a valid flightplan active in the FMC? If I program the PERF INIT page with aircraft data and specify thrust, v-speeds, etc., will the thrust reduction function work if I use the MCP without LNAV and VNAV?Thanks!Jonathan

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Is the FMC governed thrust reduction function still supposed to work even if one is not flying with a valid flightplan active in the FMC? If I program the PERF INIT page with aircraft data and specify thrust, v-speeds, etc., will the thrust reduction function work if I use the MCP without LNAV and VNAV?Thanks!Jonathan
Yes but you must push the THR button when your ready for climb thrust.Rob

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The TMC (Thrust Management Computer) will still command different N1/EPR thrust limits with or without a LNAV route. You can also manually select thrust limits by going to the FMC ---> Initialization Reference ----> Thrust Limit page. It should also select thrust commands even without the performance data entered.

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The TMC (Thrust Management Computer) will still command different N1/EPR thrust limits with or without a LNAV route. You can also manually select thrust limits by going to the FMC ---> Initialization Reference ----> Thrust Limit page. It should also select thrust commands even without the performance data entered.
I think he's talking about the aircraft automatically selecting CLB THRUST when flying circuits for example.This is not possible, you need to select it yourself by pushing the THR button. You could of course select it in the FMC but normal SOP is for the pilot flying is to remain on the T/O Preformance page during departure.Rob

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I think he's talking about the aircraft automatically selecting CLB THRUST when flying circuits for example.This is not possible, you need to select it yourself by pushing the THR button. You could of course select it in the FMC but normal SOP is for the pilot flying is to remain on the T/O Preformance page during departure.Rob
You're correct, the aircraft doesn't select CLB thrust automatically. That becomes active when you select TOGA. I don't think that was what the OP asked though.s the FMC governed thrust reduction function still supposed to work even if one is not flying with a valid flightplan active in the FMC? If I program the PERF INIT page with aircraft data and specify thrust, v-speeds, etc., will the thrust reduction function work if I use the MCP without LNAV and VNAV?Governed thrust reduction will work as long as you have an assumed derated temperature in the TO thrust page.

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Maybe we need some clarity from the original poster.If someone uses the term Thrust reduction that is normally associated with CLB THRUST at a certain altitude.Reduced thrust or assumed temperature as you know is completely different.CheersRob

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Maybe we need some clarity from the original poster.If someone uses the term Thrust reduction that is normally associated with CLB THRUST at a certain altitude.Reduced thrust or assumed temperature as you know is completely different.CheersRob
OK, let me try to clarify. I am practicing takeoffs and climbouts but I am not using a flightplan or the LNAV and VNAV functions. I am entering data in the PERF INIT page and selecting or modifying takeoff and climb thrust in the appropriate FMC page. I almost always select some kind of power de-rate or reduced power function in the FMC pages. I am selecting 1000 or 1500 feet as the thrust reduction altitude. I use the A/T and I hit the TOGA button during N1 spoolup on the takeoff roll. I then takeoff but I find that as I fly through the thrust reduction altitude, there is no change from TOGA power which kicked in at takeoff. No type of CLB power takes over or is indicated on the EICAS. I am asking whether it supposed to be this way? If I use the VNAV function with a valid flightplan, then the thrust reduction kicks in as programmed but it does not seem to work with my practice takeoffs with no flightplan, et al. [i am aware that the THRUST button kicks you into full CLB power but I am not using that and I hardly ever use it for any purpose.]Hope this clarifies.Jonathan

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Did you engage a new vertical mode like FLCH or V/S? As far as the FMA is concerned, you're still taking off if you haven't selected a climb mode.

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Did you engage a new vertical mode like FLCH or V/S? As far as the FMA is concerned, you're still taking off if you haven't selected a climb mode.
Good point, BatMan. I think you are correct. I experimented with the PSS 777 changing vertical modes from TOGA on climbout and that DID produce an instant change to the FMC programmed climb thrust. I believe it worked similarly with the PMDG 744, but I need to check again tonight. In any event, I guess the question is answered by now in essence: you have to manage the automation to get climb thrust engaged in the circumstances I describe. Jonathan

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lol thats what I said in the first place, push the THR button on the MCP thats what you would do in the real aircraft, it's there for a reason.Rob

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lol thats what I said in the first place, push the THR button on the MCP thats what you would do in the real aircraft, it's there for a reason.Rob
Well, yes and no: my question was whether the automation of the FMC would work to provide to kick one into climb thrust and the answer to that is No. The further answer is that you need to press the THR button or use the MCP to select a different vertical mode.Jonathan

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lol thats what I said in the first place, push the THR button on the MCP thats what you would do in the real aircraft, it's there for a reason.Rob
I don't think that was his question. I think he had TOGA thrust armed from takeoff, but didn't select a climb mode at the AH. If you do it that way, the FMA will read: |THR HLD| TO | TO | and F/D will be displayed above the attitude indicator. TO thrust will be displayed above N1/EPR until either a new climb mode or thrust mode is selected.

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I don't think that was his question. I think he had TOGA thrust armed from takeoff, but didn't select a climb mode at the AH. If you do it that way, the FMA will read: |THR HLD| TO | TO | and F/D will be displayed above the attitude indicator. TO thrust will be displayed above N1/EPR until either a new climb mode or thrust mode is selected.
Yes, that is exactly the case. Thanks.Jonathan

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Original question 'will the thrust reduction function work if I use the MCP without LNAV and VNAV?'Original answer 'Yes but you must push the THR button when your ready for climb thrust'I give up lolRob

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Original question 'will the thrust reduction function work if I use the MCP without LNAV and VNAV?'Original answer 'Yes but you must push the THR button when your ready for climb thrust'I give up lolRob
Don't worry Rob, I understood you from the first time .... :(

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