Pitch change after mode selection

Aircraft state

If the flight path is unsuitable, take control and establish a safe pitch, speed and climb before investigating.

Read the FMA

Record the active vertical mode, thrust mode and selected speed. A selected mode and a captured mode are different.

Consider FLCH

FSS describes FLCH as controlling speed with pitch. A target above the current speed can command acceleration; the available thrust and selected altitude influence the resulting path.

Check ALTSEL

Confirm that the selected altitude is appropriate to the intended climb. FSS says that selecting an altitude below the aircraft during a FLCH climb commands a descent; selecting an altitude above it during a FLCH descent commands a climb.

Check thrust

Verify autothrottle status, thrust setting and actual engine response. A speed target alone does not create climb performance.

Check controls

Inspect trim and throttle bindings and simulator assistance. If you suspect a trim input, monitor the EICAS pitch-trim indication during a suitable controlled simulator check. Record the targets, source colours, A/T state and FMA.

Reproduce the event

Change one variable after stabilising.

After stabilising, repeat only if appropriate with one variable changed and record the exact build and conditions.

Service Update 1 lists pitch/roll oscillation and autothrottle speed wander among the fixes in version 1.1.0. If either still occurs in that build, record the FMA, selected targets, aircraft version and control bindings; an older beta report alone does not show that the current build has the same fault. FSS Service Update 1 ^[2]. ^[38]