737 MAX Flight Crew Operations Manual
Flight Management, Navigation -
FMC Takeoff and Climb
MN-FLT-OH-201
11.41.5
• waypoint speed constraints, or
• the speed restriction associated with the origin airport, whichever is
more restrictive.
Climb Profile Speed Target Exceptions
An exception to the standard climb speed profile is flown:
• if VNAV initiates a level off prior to reaching the acceleration height for
either of the following reasons, then the speed target changes at the level
off initiation as though the airplane had reached the planned
acceleration height.
•profile altitude constraint or MCP altitude capture.
•cruise altitude capture.
• if an engine failure is detected, target speed will be last MCP speed (V2)
+ 20 kts if the airplane is at that speed or greater, or the existing speed if
the airplane is between V2 and V2 + 20 kts
• if an engine failure is detected and the engine out acceleration height is
reached or VNAV guidance initiates a level-off prior to engine out
acceleration height the VNAV target speed will change to VREF + 70
KCAS (flaps up maneuver speed)
At the climb thrust reduction point, the FMC commands a reduction to the selected
climb thrust. Passing 10,000 feet, VNAV commands an acceleration to the
economy climb speed, which is maintained until entering the cruise phase.
Waypoint speed constraints take priority if slower than target speed.
During the climb, VNAV complies with the LEGS page waypoint altitude and
speed constraints. A temporary level–off for a crossing altitude restriction is
accomplished at the current commanded speed.
When the climb speed profile causes an anticipated violation of a waypoint
altitude constraint, the FMC displays the CDU scratchpad message UNABLE
NEXT ALTITUDE. A different speed profile that provides a steeper climb angle
must be manually selected.
When the speed profile causes an anticipated violation of a waypoint speed
constraint, the FMC displays the CDU scratchpad message UNABLE YYY
KNOTS AT XXXXX, where speed is YYY and waypoint is XXXXX.
If a CLB 1 or CLB 2 derate is selected, the derate is maintained for the initial part
of the climb. Thrust eventually increases to maximum climb thrust by 15,000 feet.
March 1, 2021
