Unexpected thrust-lever or A/T state

Record the starting state

Note the FMA thrust mode, selected speed, actual airspeed, flight phase and virtual lever positions.

Check the EFB option

Open Settings, then Aircraft. Note whether Overridable Autothrottle is enabled. FSS says that, when enabled, the thrust levers can override A/T without disconnecting it.

A/T disconnect logic

The Procedure Guide says user throttle input disconnects A/T except below 60 kt. The thrust-quadrant page says it disconnects above 60 kt. The pages do not say clearly whether these general rules apply only with Overridable Autothrottle off; they also differ at exactly 60 kt. Check the installed build and observe the FMA.

Check the axis

Look for duplicate assignments, axis noise, detent miscalibration or an external application sending commands.

Read the mode

On the FMA, SPDt means speed-on-thrust; SPDe means speed-on-elevator. FSS says HOLD prevents unwanted lever movement and engages at or above 60 kt during the takeoff roll. OVRD indicates override; LIM means A/T authority is insufficient to achieve or maintain the selected airspeed. Compare the actual lever response with the active mode.

Repeat carefully

Keep build, setting, hardware and FMA.

In a safe setup, repeat the same flight phase and change one setting at a time. Watch both physical and virtual levers.

Control response

Note the aircraft version, airspeed, EFB option, hardware and FMA. ^{[91] [9] [51]}

After an A/T disconnect, FSS describes a flashing green AT indication for a normal disconnect and a flashing amber AT indication for a non-normal disconnect. A second press of an A/T disconnect switch or the A/T guidance-panel button acknowledges it. For HOLD during the takeoff roll, the thrust-quadrant page specifies 60 KIAS. FSS thrust lever quadrant ^[51].

FSS lists automatic A/T disconnection after touchdown, with the thrust levers beyond TO/GA, or when reverse is selected during a rejected takeoff. It also lists an autothrottle failure or a thrust-lever-angle difference greater than 8° as non-normal disconnect causes. Check the FMA and the actual lever positions before deciding what happened. FSS thrust lever quadrant ^[51].