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There is a feedback mechanism to engine throttle that is immediate and physically obvious: The thrust levers. They will move to indicate the amount of thrust the engines are ordered to produce, even when under autothrottle control.

If a pilot doesn't pay attention to where his thrust levers are when appropriate thrust is critical to safe flight, that is pilot error.

A go-around isn't complicated enough to merit reliance on automation anyway: Max thrust (or whatever is appropriate), pitch up and climb according to ATC orders or go-around procedure at airport, landing gears up, and come back for another landing attempt.




There is a button they use on go around that turns on auto throttle up, which they hit. In the scenario they thought they were in, they don’t directly interact with the throttle levers. They were paying attention to other things, like they were supposed to.

In this scenario, the auto throttle doesn’t auto throttle up because unexpectedly, they were partially wheels down for a moment, and that disables auto throttle up.

Oops.


However the levers do physically move forward and the EPR indication should spool up when the TO/GA button is pressed. Many moons ago, one of my instrument instructors was insistent on physical verification of control status even in light(er) aircraft. You didn’t take your hand off the gear lever until you saw 3 green. On takeoff or go-around, especially go-around, you kept one hand on the throttle levers until after positive rate of climb was achieved. Had the PF here had that practice, the accident would not have occurred. That said, if the TO/GA button is unavailable in a given flight mode, a more obvious verbal annunciation of that mode should be made by the aircraft.


> On takeoff or go-around, especially go-around, you kept one hand on the throttle levers until after positive rate of climb was achieved.

On multi-engine jets, common training is to remove your hand from the throttle at V1 (takeoff decision speed). Most problems after that speed are to be taken airborne and dealt with there.


Nod, and they changed their training to make many of those changes after this accident - one of about 40 changes.

Definitely one of those ‘if the PIC had been a little more paranoid, and a bunch of other rare/weird things had not happened, it would have been fine’ type accidents. The first officer was supposed to also verify things, but the specific step wasn’t in the training either, and wasn’t normally applicable because of the TO/GA automation.

Luckily no loss of life from the crash directly. If the firefighters had listened to prior crash issues and fixed them in their own response, likely no firefighters would have died either.


In the "Children of the Magenta Line" video they tell you to hold the throttles physically in place in similar situations, but not this one exactly. They want you to hold all the controls when turning on or off autopilot, changing modes, or if you think something is going wrong (this kind of plane has multiple autopilots, so weird stuff can and has happened). I guess what you could do in this case is touch the throttles to make sure they are doing what you want, and retain the ability to grab them and push them forward if the auto-throttle system is not doing it.




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