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Airbus high speed protection

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Airbus high speed protection

Old 6th Nov 2016, 00:07
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Airbus high speed protection

What happens if in the cruise (auto pilot engaged) you apply TOGA thrust? High speed protection should engaged and auto pilot disengage....nose pitch up to prevent overspeed? Then what eventually reduces the thrust, assuming it's left in TOGA?

Thanks
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Old 7th Nov 2016, 01:35
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Hi
I dont know any engine protection which would reduce to mct.
However, the high speed prot will induce a climb to reduce speed
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Old 7th Nov 2016, 15:10
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TOGA is TOGA and there's nothing the A/Thr can do about it.
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Old 7th Nov 2016, 15:36
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Setting TOGA after FLX/MCT a/thr will disconnect and revert to armed , i think protection will add nose up a/p disconnect ,with TOGA until power is manually reduced , in this scenario.
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Old 7th Nov 2016, 17:03
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won't disconnect but will become armed from active and will remain so.
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Old 7th Nov 2016, 17:56
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Not sure about Airbus (although I'd be mildly surprised if it's different), but on Boeing TOGA isn't defined outside of the Takeoff envelope (above 250 knots and 15k-17k altitude, depending on the aircraft model).
Above that, full forward throttle gives Max Con.
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Old 8th Nov 2016, 00:01
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Hi
Nothing happens, except for toga flashing in white.
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Old 8th Nov 2016, 00:56
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Originally Posted by SADDLER
Hi
Nothing happens, except for toga flashing in white.
why will it flash? It will only show MAN TOGA
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Old 8th Nov 2016, 09:11
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Maybe he ment LVR CLB? With A/THR armed, it is not beyond my imagination ...
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Old 8th Nov 2016, 12:54
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Hmmm
As as far as I can remember it was toga flashing in white.
Could be wrong.
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Old 8th Nov 2016, 13:31
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Then what eventually reduces the thrust, assuming it's left in TOGA?
Hopefully the idiot siting in the seat at the front will reduce it, after seeing what happens if he does this to see what will happen.
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Old 8th Nov 2016, 13:42
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Originally Posted by FlightDetent
Maybe he ment LVR CLB? With A/THR armed, it is not beyond my imagination ...
FD for lever climb to flash you need THR RED altitude. It cannot happen at in cruise phase.
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Old 8th Nov 2016, 13:47
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Originally Posted by roofdog
What happens if in the cruise (auto pilot engaged) you apply TOGA thrust? High speed protection should engaged and auto pilot disengage....nose pitch up to prevent overspeed? Then what eventually reduces the thrust, assuming it's left in TOGA?

Thanks
Protections have been designed considering the fact there are 2 rated and proficient pilots at the controls. Hopefully, like it has already been mentioned, at least 1 will think about reducing the thrust like when you're in the car on your way to the airport called from stby and you lift your foot off the pedal when you see the cops.
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Old 8th Nov 2016, 14:42
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tdracer
but on Boeing TOGA isn't defined outside of the Takeoff envelope (above 250 knots and 15k-17k altitude, depending on the aircraft model).
Above that, full forward throttle gives Max Con.
In airbus chart TOGA is given up to FL145. But MCT and MAX CLB are given up to FL390 but the difference between them is of the order of .3/.4 %N1. At cruise level TOGA and MCT should be same.
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Old 8th Nov 2016, 23:23
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lever climb to flash you need THR RED altitude. It cannot happen at in cruise phase.
Oh yes it can. DSC-22_30-100 "B" LVR CLB flashing white - Request to set the thrust levers in CL detent in the case not in position while the aircraft is above the altitude of thrust reduction with both engines running.

Whenever the A/THR is armed and the TLs are not in the CLB detent, you'd get told by the aircraft they're not where expected. The first instance is passing ACC ALT in after take-off, indeed.
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Old 9th Nov 2016, 04:25
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FlightDetent
Oh yes it can. DSC-22_30-100 "B" LVR CLB flashing white - Request to set the thrust levers in CL detent in the case not in position while the aircraft is above the altitude of thrust reduction with both engines running.
The discussion is about cruise phase with thrust levers in TOGA. You have transited TO phase and you are not in GA phase. There is no thrust reduction altitude in cruise.The statement you have quoted is not applicable in cruise phase.
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Old 9th Nov 2016, 05:20
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Originally Posted by vilas
FlightDetent

The discussion is about cruise phase with thrust levers in TOGA. You have transited TO phase and you are not in GA phase. There is no thrust reduction altitude in cruise.The statement you have quoted is not applicable in cruise phase.
Correct. In addition with 2 engines running past the CLB detent you are out of the A/THR active zone so the system lets you use any other thrust setting position you may require (MCT or TOGA) although as stated before the increase in thrust specifically at high altitude is minimal.
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Old 9th Nov 2016, 08:32
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I may be wrong but I thought I read somewhere that Airbus modified the logic in the A380 and A350 and overspeed protection on these aircraft does reduce thrust automatically.

Can anyone confirm this or tell me I'm wrong?
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Old 9th Nov 2016, 09:02
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Up to A330 when ATHR is blue there is no protection. But with ATHR active may be in THR CLB or THR IDLE and if you do not fly FDs properly and speed reaches either MAX speed or drops below VLs the FMA is removed and ATHR reverts to speed and managed speed target changes to selected to recover the speed.
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Old 9th Nov 2016, 17:46
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Up to A330 when ATHR is blue there is no protection
Agree, except alpha-floor.
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