MCT at cruise
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A320 MCT at cruise
Say you have a situation in cruise where you need to goose the power a bit more than the A/T is giving you. Does going into MCT make a difference? Is it advised? Pointless?
Conversely, hitting a wave and heading toward overseer, does moving the levers to IDLE make a difference?
Conversely, hitting a wave and heading toward overseer, does moving the levers to IDLE make a difference?
Last edited by Altcrznav; 25th Sep 2013 at 22:26.
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Well I do it at high alt in cruise in the B737NG.
Remember, you just change your trust Limit. Might come in handy in turbulence or a turn.
Common sense, really.
Remember, you just change your trust Limit. Might come in handy in turbulence or a turn.
Common sense, really.
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Thanks for intruding,
I am talking about speed deviations at altitude. You can shove your thrust levers up and down by yourself if you wish yo do so of course. I prefer the A/T during hours of cruise.
I am talking about speed deviations at altitude. You can shove your thrust levers up and down by yourself if you wish yo do so of course. I prefer the A/T during hours of cruise.
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If you are using MCT for anything other than getting out of an unforeseen low speed situation at hight alt OR an engine failure, then you need to have a good long think about what you are doing.
For those who think this is "common sense" read "complete stupidity". Common sense in not going up so high in turbulent conditions or if you need it for a turn?????
For those who think this is "common sense" read "complete stupidity". Common sense in not going up so high in turbulent conditions or if you need it for a turn?????
Last edited by victorc10; 26th Sep 2013 at 07:23.
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Just push the thrust levers full forward; or "conversely", just pull them all the way back!
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If the engines have full climb thrust targeted, moving the lever to MCT or TOGA makes no difference at cruise altitude, where CLB, MCT and TOGA thrust limit are the same. (I haven't seen this written down, however I have tried it out).
If you are in overspeed with ATHR on, idle will be targeted anyway. Hence the QRH overspeed line: Thrust reduction....... Monitor. (If Athr on), so closing the thrust levers will achieve nothing.
For what it's worth, when I am flying the A320 (and especially the A321) in turbulence with large airspeed variation, I switch to speed mode from mach. The Autothrust pins the speed very well compared to the lack lustre performance in mach. On the A321 where the VLS to VMax is often tight, this can really help. Obvious caveat, watch your mach with changing temperature.
If you are in overspeed with ATHR on, idle will be targeted anyway. Hence the QRH overspeed line: Thrust reduction....... Monitor. (If Athr on), so closing the thrust levers will achieve nothing.
For what it's worth, when I am flying the A320 (and especially the A321) in turbulence with large airspeed variation, I switch to speed mode from mach. The Autothrust pins the speed very well compared to the lack lustre performance in mach. On the A321 where the VLS to VMax is often tight, this can really help. Obvious caveat, watch your mach with changing temperature.
Last edited by tom775257; 26th Sep 2013 at 12:51.
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Boeing article recommends using speed brakes for speed control(overspeed condition/potential) instead of large power reduction. Quicker speed correction and avoids engine spool problems.
Last edited by misd-agin; 26th Sep 2013 at 13:36. Reason: added (overspeed condition/potential)
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Front range of the Rocky Mountains, every winter we have mountain waves, and company procedure is to use speedbrakes and MCT to mitigate, MCT and Climb trust is the same at altitude.... Let me add I have seen airspeed change 50Knots in seconds, MCT/ Climb to power out is totally acceptable.
Last edited by 737ngpilot; 26th Sep 2013 at 15:12.
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Just push the thrust levers full forward; or "conversely", just pull them all the way back!
Common sense in not going up so high in turbulent conditions or if you need it for a turn?????
misd-agin Boeing article recommends using speed brakes for speed control(overspeed condition/potential) instead of large power reduction. Quicker speed correction and avoids engine spool problems.
Last edited by de facto; 26th Sep 2013 at 14:55.
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The OP still refuses to give an airplane or engine type, or tell us whether this is a real or FlightSim question...
If the autothrottles are not keeping up with external influences, whether it be mountain wave, turbulence, wind shear, or something else, then the simple answer is to take over manually, regardless of what someone might "prefer". If the conditions are so extreme that the autothrottles command IDLE as he posited, then "loss of separation" is not likely an immediate factor. If you are pushing the red line AND climbing in a wave, spool-up time should also not be an immediate factor unless you got into a "coffin corner" situation in the first place, whether by bad planning or extreme bad luck.
I do agree with misd-agin that speedbrakes are preferable to excessive thrust reduction at high altitude. However, the question appeared to be regarding the ability to control the thrust. Anyone who "prefers" to use autothrottles to control thrust when a described extreme/limiting/edge-of-the-envelope situation exists is not someone I'd "prefer" to fly with.
If the autothrottles are not keeping up with external influences, whether it be mountain wave, turbulence, wind shear, or something else, then the simple answer is to take over manually, regardless of what someone might "prefer". If the conditions are so extreme that the autothrottles command IDLE as he posited, then "loss of separation" is not likely an immediate factor. If you are pushing the red line AND climbing in a wave, spool-up time should also not be an immediate factor unless you got into a "coffin corner" situation in the first place, whether by bad planning or extreme bad luck.
I do agree with misd-agin that speedbrakes are preferable to excessive thrust reduction at high altitude. However, the question appeared to be regarding the ability to control the thrust. Anyone who "prefers" to use autothrottles to control thrust when a described extreme/limiting/edge-of-the-envelope situation exists is not someone I'd "prefer" to fly with.
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737ngpilot: you look like a pilot who's been there, done that and knows what the question was.
To you intruder:
I am talking about daily ops, not extremes. And yes, in an airplane, not FS.
Stupid being at that level? You have not flown long range overwater yet, or over parts of the world, where two way comms are difficult or not available. Or maybe you choose by default Fl 280 for a long stretch?
Anyway, feel free to choose another flight if it happens me to be the skipper.
To you intruder:
I am talking about daily ops, not extremes. And yes, in an airplane, not FS.
Stupid being at that level? You have not flown long range overwater yet, or over parts of the world, where two way comms are difficult or not available. Or maybe you choose by default Fl 280 for a long stretch?
Anyway, feel free to choose another flight if it happens me to be the skipper.
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Intruder
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Just push the thrust levers full forward; or "conversely", just pull them all the way back!
Are you a pilot, or is this another Flight Sim question?
Join Date: May 2000
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Just push the thrust levers full forward; or "conversely", just pull them all the way back!
Are you a pilot, or is this another Flight Sim question?
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The reason I ask is that at cruise, the donuts and the max EPR ticks are in line with each other. So does moving out of CLB really give you more thrust?
I say no.
I say no.
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Hey intruder, how about you take it down a notch.
I didn't refuse to clarify anything. I'm not on this board daily it may take me a few days to response to posts.
Calm down.
A320 (check the title)
And I don't know why the engine type has anything to do with it but we have IAE V2500s.
I didn't refuse to clarify anything. I'm not on this board daily it may take me a few days to response to posts.
Calm down.
A320 (check the title)
And I don't know why the engine type has anything to do with it but we have IAE V2500s.
Last edited by Altcrznav; 27th Sep 2013 at 01:47.