Check lateral and vertical capture

Lateral and vertical guidance do not have to change at the same height. Read the two mode columns separately as the aircraft climbs.

Ground FMA

Check the active route, initial cleared altitude, takeoff data and armed modes. Note the departure capture setting.

At liftoff

Follow the displayed takeoff guidance and monitor the aircraft. Check climb performance and the selected target.

Lateral mode

FSS describes armed LNAV engaging after passing 200 ft during climb. Confirm the change on the FMA and check that the commanded path matches the clearance.

Vertical mode

FSS separately describes a VNAV capture height set on DEPARTURE LIMIT. The documented default is 800 ft above field elevation, not necessarily the height set for your flight.

Mode capture

Compare the FMA, speed target, pitch, thrust and selected altitude. A mode can be armed without having captured.

FMA disagreement

Maintain a safe flight path, select suitable guidance and check the active mode and selected targets.

The FSS lateral-mode page gives 200 ft for LNAV engagement during climb but does not state a height reference in that passage. The supplied real-aircraft SOPM specifies 200 ft AGL for its post-modification LOAD 27.1 example ^{[L01, PDF p. 192]}. This does not establish the reference used by the FSS simulation. Check the FMA and aircraft response.

FSS lists a default departure speed schedule of V2 + 10 kt to 1,000 ft, followed by 210 kt to 2,500 ft. That passage does not state the height reference. These are default FMS values, not a clearance or values to copy without checking the aircraft. Read the speed target and departure-limit settings for your flight, and respect the applicable speed and flap limits. FSS speed control ^[50]. ^{[37] [24]}