787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Management, Navigation -
Flight Management System
Operation
Copyright © The Boeing Company. See title page for details.
11.31.22 D615Z003-TBC
MCP Altitude Intervention
Whenever the airplane levels off at an MCP altitude not in the FMC, VNAV ALT
annunciates. For example, FMC cruise altitude is FL250 and the clearance
altitude, FL190, is set in the MCP. Pitch maintains altitude and thrust maintains
FMC target speed. In the example, the speed after the temporary level off would
be ECON CLB SPEED.
Setting the clearance altitude in the MCP window and pushing the altitude selector
continues the climb. VNAV SPD activates. Pitch maintains FMC speed and thrust
increases to the armed reference thrust limit. In the example, the airplane climbs
to FMC CRZ ALT and then levels at FL250 in cruise.
Cruise
During cruise, the FMC commands economy cruise speed or the pilot entered
speed until reaching the top–of–descent (T/D) point. Other cruise speed options
are:
• long range (LRC)
• engine out (ENG OUT)
• flight crew entered speed
• flight crew entered constant Mach between two or more waypoints
• required time of arrival (RTA)
The FMC commands maximum range cruise speed with the cost index set to zero.
Cost index modifications are allowed until passing the top of descent.
Step Climb
Fuel and ETA predictions assume the airplane climbs at each predicted step climb
point as airplane weight decreases. FMC predicted step climb increments are
based on the step size shown on the CRZ page. Entering a step size of zero causes
the FMC to assume a constant altitude cruise.
10,000'
T/C
E
C
O
N
C
L
B
FL190
Temporary Level Off
VNAV ALT
Altitude Selector Pushed
FL250
S
P
D
ALTITUDE INTERVENTION EXAMPLE
August 14, 2009
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