
737 MAX Flight Crew Operations Manual
Flight Management, Navigation -
Flight Management System
Operation
MN-FLT-OH-201
11.31.31
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VNAV starts an early descent at 1000 fpm and captures the idle descent path.
VNAV uses FMC SPD for the autothrottle mode and VNAV PTH for the pitch
mode.
Approach
The FMC transitions to “on approach” when the airplane is within:
• 2 NM of the first approach waypoint (including approach transitions
such as arcs and procedure turns), or
• 2000 feet of airport elevation, whichever occurs first.
When the FMC is “on approach”, the following features are available:
• UNABLE RNP alerting levels are higher
• when preparing for a missed approach and the MCP altitude is set at
least 300 feet above the current airplane altitude, VNAV remains in
VNAV PATH.
• if the airplane is more than 200 feet below the vertical path, VNAV
commands zero vertical speed until intercepting the path.
Note:
Display of a specified path angle is not limited to approaches. A path angle
may be defined for a leg in a STAR and displays on the RTE LEGS page
for the procedure.
The FMC transitions out of “on approach” under the following conditions:
• selecting TO/GA
• the airplane lands
• the waypoint cycles to the first waypoint of the missed approach
• executing a direct-to waypoint in the missed approach.
The following situations are generally encountered during approach operations,
but are not determined by “on approach” logic:
• If speed intervention is engaged:
•during a path descent with flaps up on an idle or non-idle leg, VNAV
switches to VNAV SPD
•with flaps down, VNAV remains in VNAV PTH
T/D
DES NOW
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March 1, 2021