Which AFDS generated pitch mode is displayed on the FMA when level at a VNAV constrained altitude?

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Multiple Choice

Which AFDS generated pitch mode is displayed on the FMA when level at a VNAV constrained altitude?

When the airplane is following a VNAV vertical profile that includes altitude constraints, the autopilot’s pitch is guided by the VNAV path. The message on the flight mode annunciator reflects that: it shows VNAV PTH. This means the aircraft is still executing the VNAV vertical guidance and staying on the calculated path to meet the constraints, even if the aircraft happens to be level at that constraint moment. You’d see a different display if you had actively switched to a pure altitude-hold behavior—level change—where the system would hold a specific altitude independently of the VNAV profile. The other modes—MCP SPD, VNAV SPD—pertain to speed control rather than the current path-following pitch guidance, so they aren’t the correct indicator here.

When the airplane is following a VNAV vertical profile that includes altitude constraints, the autopilot’s pitch is guided by the VNAV path. The message on the flight mode annunciator reflects that: it shows VNAV PTH. This means the aircraft is still executing the VNAV vertical guidance and staying on the calculated path to meet the constraints, even if the aircraft happens to be level at that constraint moment.

You’d see a different display if you had actively switched to a pure altitude-hold behavior—level change—where the system would hold a specific altitude independently of the VNAV profile. The other modes—MCP SPD, VNAV SPD—pertain to speed control rather than the current path-following pitch guidance, so they aren’t the correct indicator here.

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