787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Flight Management, Navigation -
Flight Management Computer
Copyright © The Boeing Company. See title page for details.
11.32.4 D615Z003-TBC
Derated Thrust Climb
[Option – Thrust climb derate]
During climb, CLB 1 and CLB 2 derates are gradually removed. In cruise, the
thrust reference defaults to CRZ. The reference can be manually selected on the
THRUST LIM page.
Two fixed climb thrust derates (CLB 1 and CLB 2) can be selected on the
THRUST LIM page. The percentage of derate can be 5%, 10%, 15% or 20% as
configured by each individual airline in their AMI file. The derated climb thrust
is maintained until reaching a predetermined altitude where the thrust then
increases linearly with altitude to achieve CLB thrust at the washout altitude.
A washout altitude option is configured by each individual airline in their AMI
file. The washout altitude options available are:
• 10,000 - 12,000 feet
• 10,000 - 30,000 feet
• 25,000 - 33,000 feet
• 25,000 - 40,000 feet
• 30,000 - 40,000 feet
For example, a 12,000 foot washout option results in using the armed climb thrust
derate (e.g. CLB 1) until the airplane reaches 10,000 feet, followed by a linear
increase in thrust until the airplane reaches 12,000 feet, where full climb thrust is
restored.
Use of an assumed temperature reduced thrust takeoff or takeoff derate affects
automatic selection of the climb derate. If the takeoff derate percentage (fixed
derate plus assumed temperature method) is:
• less than CLB 1 then CLB is selected
• greater than or equal to CLB 1 and less than CLB 2 then CLB 1 is selected
• greater than or equal to CLB 2 then CLB 2 is selected
On the ground, the pilots may override the automatic climb derate selection after
the takeoff selection is complete.
Use of derated climb thrust reduces engine maintenance costs, but increases total
trip fuel.
Fuel Monitoring
The FMC receives fuel data from the fuel quantity system or from manual entries.
Fuel quantity values display on the PERF INIT page as calculated (CALC),
MANUAL, or SENSED. They display on PROGRESS page 2/4 as TOTALIZER
and CALCULATED. TOTALIZER and SENSED values are the same data with
different names.
August 14, 2009
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