Secure
The flight crew should ensure the following actions are accomplished as required:
Copyright . The Boeing Company. See title page for details.
SP.16.6 D6-30151-425 April 01, 2001
Supplementary Procedures -Adverse Weather
747 Operations Manual
Outflow Valve Manual switches .........................................................ON
Outflow Valve Manual control .................................................... CLOSE
Inhibits intake of snow and ice. Wheel chocks....................................................................Check in place Parking brakes .................................................................................. OFF
Eliminates the possibility of brakes freezing.
Protective covers and plugs ........................................................Installed
Water storage containers..............................................................Drained
Toilets ..........................................................................................Drained
Doors ............................................................................................Closed
Hot Weather Operation
During flight planning, consider the following:
.
high temperatures inflict performance penalties which must be
taken into account on the ground before takeoff
.
alternate takeoff procedures (Packs Off Takeoff, APU-to-Pack
Takeoff, etc.) During ground operation, consider the following to help keep the airplane as cool as possible:
.
all packs should be used (when possible) for maximum cooling
.
recirculation fans should be off because the fans add warm air to
the conditioned air
.
if cooling air is available from an outside source, the supply should
be plugged in immediately after engine shutdown and should not
be removed until just prior to engine start
.
keep all doors and windows, including cargo doors, closed as much
as possible
.
electronic components which contribute to a high temperature level
in the flight deck should be turned off while not needed
.
all air outlets on flight deck should be open
Copyright . The Boeing Company. See title page for details.
April 01, 2001 D6-30151-425 SP.16.7
Supplementary Procedures -Adverse Weather 747 Operations Manual
. close all window shades on the sun–exposed side of the passenger
cabin
Brake temperature levels may be reached which can cause the wheel fuse plugs to melt and deflate the tires. Consider the following actions:
.
be aware of brake temperature buildup when operating a series of
short flight sectors. The energy absorbed by the brakes from each
landing is cumulative
.
extending the landing gear early during the approach provides
additional cooling for tires and brakes
.
in–flight cooling time can be determined from the “Brake Cooling
Schedule” in the Performance–In flight section
Engine Operation in Heavy Rain or Hail
If heavy rain or hail encountered or anticipated:
Continuous Ignition switch ........................................................... ON Provides flameout protection and maintains a minimum thrust setting of approach idle. Confirm CON IGNITION memo message is displayed.
During descent:
Autothrottles ................................................................ Disconnect
Note: In heavy precipitation, engine parameter fluctuations may occur, particularly a noticeable drop in EGT. Engine parameters will return to normal immediately upon leaving the area of heavy precipitation. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址:747-441 Operations Manual 747操作手册(55)