Okay button on side of the throttle handles is the Auto Throttle Disconnect right? So say for example a pilot suddenly needs to seperate the throttles so that one is giving more power than the other. If you press the auto throttle disconnect you can move the levers independently then or must another button be pressed somewhere?Another example would be in a 747-400 and suddenly you had to shut an engine down. How do you seperate one lever and pull it back to idle without interupting the other 3?

there is no auto throttle in that case, it will be disengaged and disabled.

So say for example a pilot suddenly needs to seperate the throttles so that one is giving more power than the other. If you press the auto throttle disconnect you can move the levers independently then or must another button be pressed somewhere?

First of all you can move the levers at all times, even if you have to counteract the A/T servos. However once you release the levers (and didn't kick out A/T) they will of course go back to whatever A/T deems necessary. Other than that, for the situation you described (could practically be an engine failure, e. g. have one failed and you need more power on the other one), the very first memory item is always to disconnect the A/T, and yes, SOP for any A/T disconnection is by the instincive switches on the thrust levers. You'd actually never shut down the A/T system by manually placing the A/T ARM switch to off.And no, there is no other button that needs to be pressed.One last thing (although I'd have to double check that) I don't believe A/T will remain engaged if you manually seperate the levers by a certain angle.

Okay button on side of the throttle handles is the Auto Throttle Disconnect right? So say for example a pilot suddenly needs to seperate the throttles so that one is giving more power than the other. If you press the auto throttle disconnect you can move the levers independently then or must another button be pressed somewhere?Another example would be in a 747-400 and suddenly you had to shut an engine down. How do you seperate one lever and pull it back to idle without interupting the other 3?

That's it. Disconnect and you're done.

One last thing (although I'd have to double check that) I don't believe A/T will remain engaged if you manually seperate the levers by a certain angle.

I believe that's correct

Thanks guys, seems like a dumb question I know but I have never had to sperate the throttles before. So thats why I had to ask.

You'd actually never shut down the A/T system by manually placing the A/T ARM switch to off.

Doesn't the A/T disconnect button on the throttle cause the solenoid in A/T Arm switch to turn it off anyway, thus achieving the same thing?

Doesn't the A/T disconnect button on the throttle cause the solenoid in A/T Arm switch to turn it off anyway, thus achieving the same thing?

Yes, correct of course that the outcome is the same. I'm just saying you'd use the instinctive switch, not the ARM switch, to do that. Of course you *can* use either one, but you also wouldn't disco the AP by pressing CMD, but rather use the instinctive yoke disco switch. Same story - technically you can do it of course, but I guess it's just a matter of SOP. And in case of the AP it also makes way more sense, as you can cancel the wailer using the very same button as you know.

Very informative topic. BTW I´ve been tryiing to assign a joystick button to the aforementioned A/T disconnect switch of the thrust levers. But from what I´ve seen so far from "PMDG Menu" in the CDU, I discovered you cannot map a keyboard key to this switch. Is that correct? The only assignment I´ve seen thus far in the "key assignment menu"is for the A/T Arm switch of the MCP, and I know for a fact that crews worldwide will under normal procedures leave this always armed (like someone previously stated). So am I missing something here?

Hi,Yeah, I also can't asign joystickbuttons via the FMC. But I have mapped a key comand to the button and entered that into the FMC. Works also good!

That´s not what I meant xxJohnxx, but thanks for the reply. What I meant is; I don´t know whether it is available at all to assign a keyboard assignment to the AT disconnect switch (the one on the side of the levers). If it were, it would be a simple matter of creating a key assignment and then mapping it to the joystick using the dedicated software. The Queen comes with the option of assigning a key to this switch so I think the NGX does also. I just can´t find it on the Options menu of the CDU.

That´s not what I meant xxJohnxx, but thanks for the reply. What I meant is; I don´t know whether it is available at all to assign a keyboard assignment to the AT disconnect switch (the one on the side of the levers). If it were, it would be a simple matter of creating a key assignment and then mapping it to the joystick using the dedicated software. The Queen comes with the option of assigning a key to this switch so I think the NGX does also. I just can´t find it on the Options menu of the CDU.

This is possible, I have both TOGA and AT disconnect switches mapped to my throttle via key-commands. The entry for the latter can be found in key-commands/autoflight/page8 - A/T disengage switch.One could also use LINDA to achieve the same thing.

This is possible, I have both TOGA and AT disconnect switches mapped to my throttle via key-commands. The entry for the latter can be found in key-commands/autoflight/page8 - A/T disengage switch.One could also use LINDA to achieve the same thing.

Thank you so much Christoph. This is exactly what I was looking for. Had trouble finding it because I thought this entry was for the AT arm switch on the MCP. Perhaps they should rename this entry on page 8 to A/T disconnect switch. I know it´s the same thing, but nomenclature sometimes gets in the way.

Thank you so much Christoph. This is exactly what I was looking for. Had trouble finding it because I thought this entry was for the AT arm switch on the MCP. Perhaps they should rename this entry on page 8 to A/T disconnect switch. I know it´s the same thing, but nomenclature sometimes gets in the way.

Sure thing. I use LINDA now, so key assignments do not matter but I remember looking through the options some time ago and getting a bit confused myself. At least the A/T arm switch assignment is labeled in the menu as such. Anyway, all is well now :-)

Okay button on side of the throttle handles is the Auto Throttle Disconnect right? So say for example a pilot suddenly needs to seperate the throttles so that one is giving more power than the other. If you press the auto throttle disconnect you can move the levers independently then or must another button be pressed somewhere?Another example would be in a 747-400 and suddenly you had to shut an engine down. How do you seperate one lever and pull it back to idle without interupting the other 3?

The 747 has one autothrottle motor driving the four thrust levers through friction clutches. If you pull the failed engine's throttle to idle the other three will continue to operate as before. No need to disconnect the A/T. If the A/T demands a power increase the "failed" throttle will move forwards the same amount as the three which are running, but you can easily drag it back to idle again.According to the manuals the NG throttles have their own motors and may disconnect if the thrust levers are split, so I don't know how the A/T would cope with a failed engine and the lever pulled to idle. See FCOM Vol 2, Pages 4.20.10 and 11. However a quick look at the QRH indicates that the A/T should be disengaged after an engine failure. In normal operation there is no reason to have one engine producing more power than the other and the EEC should take care of any throttle stagger due to engine hydromechanical set up variations.Kevin Hall

With split levers, A/T will disengage (and fail to reengage). A/T is not used in single engine operations.If you want to leave A/T armed during approach, you need to deselect the SPD switch by pressing it. The instinctive buttons will disconnect the A/T system causing a solenoid in the A/T ARM switch to move the switch to off.