曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
means of compliance that allows use of the CWT override/jettison pumps after
specified inspections/repairs. With the incorporation of this Service Bulletin, the
CWT override/jettison pumps may be used normally.
These pumps are also used in the horizontal stabilizer tanks. Selecting the
stabilizer tank pumps OFF with fuel remaining in the stabilizer tank results in
unacceptable display of the EICAS caution message FUEL STAB XFR and
violates the certified structural loads analysis. Therefore, fueling and use of the
horizontal stabilizer tank is prohibited.
The FAA has approved an alternate means of compliance with AD T98-25-52
through inspection procedures contained in Boeing Service Bulletin 747-28-2225
(December 22, 1998 Rev 2). Upon completion of the required inspections/repairs,
horizontal stabilizer fuel pumps may be used normally.
Pump damage may be accompanied by tripped fuel pump circuit breakers.
Therefore, a tripped CWT fuel pump or horizontal stabilizer pump circuit breaker
should not be reset.
Operating Instructions
Fueling and use of the horizontal stabilizer tank is prohibited until
inspections/repairs required by SB 747-28-2225 have been accomplished.
The following CWT restrictions apply until inspections/repairs required by
Service Bulletin 747-28-2226 have been accomplished:
If the CWT override/jettison pumps are required for flight, the center wing tank
must contain a minimum of 17,000 pounds (7,700 kilograms) prior to engine start.
If CWT fuel is less than 50,000 pounds (22,700 kilograms) prior to engine start,
select both CWT override/jettison pumps OFF at the first occurrence of any of the
following:
Page 4 of 6
Operations Manual Bulletin No. ILF2-41(R5), Dated April 1, 1999 (continued)
• at or before CWT fuel reaches 7,000 pounds (3,200 kilograms), or
• when either CWT fuel pump low pressure light illuminates with CWT fuel
below 7,000 pounds (3,200 kilograms); FUELOVRD CTR L & R EICAS
messages may be displayed, or
• when either FUEL OVRD CTR L or R EICAS message displays with CWT
fuel below 7,000 pounds (3,200 kilograms).
The flight crew may select the CWT Override/Jettison pumps ON in stabilized
cruise, then select them OFF when CWT fuel reaches 3,000 pounds (1,360
kilograms).
If CWT fuel is greater than or equal to 50,000 pounds (22,700 kilograms) prior to
engine start, select both CWT override/jettison pumps OFF at the first occurrence
of any of the following:
• at or before CWT fuel reaches 3,000 pounds (1,360 kilograms), or
• when either center tank fuel pump low pressure light illuminates with CWT
fuel below 3,000 pounds (1,360 kilograms); FUEL OVRD CTR L & R
EICAS messages may be displayed, or
• when either FUEL OVRD CTR L or R EICAS message displays with CWT
fuel below 3,000 pounds (1,360 kilograms).
WARNING: Do not reset a tripped CWT override/jettison or horizontal stabilizer
transfer/jettison pump circuit breaker.
NOTE:
• The CWT fuel quantity indication system must be operative to dispatch with
CWT mission fuel.
• The center wing tank may be emptied during emergency fuel jettison.
• In a low fuel situation, both CWT pumps may be selected ON and all CWT
fuel used.
Upon completion of the three Service Bulletins specified in this Operations
Manual Bulletin, CWT override/jettison and horizontal stabilizer transfer/jettison
pumps may be used normally.
Administrative Information
Insert this bulletin behind the Bulletin Record Page in Volume 1 of your
Operations Manual. Amend the Bulletin Record to show bulletin ILF2-41(R5) IN
EFFECT (IE).
This Operations Manual bulletin will be revised based on Service Bulletin
completion reported by the operator. This bulletin will be cancelled after Boeing
is notified all affected airplanes in an operator’s fleet have been inspected/repaired
as prescribed in the following Service Bulletins:
• 747-28A2212 (Rev 2)
• 747-28-2225 (Rev2)
• 747-28-2226.
Page 5 of 6
Operations Manual Bulletin No. ILF2-41(R5), Dated April 1, 1999 (continued)
Please send all correspondence regarding Operations Manual Bulletin status to
one of the following addresses:
Mailing Address:Manager, Flight Technical Publications (747-400)
Boeing Commercial Airplane Group
P.O. Box 3707 MS 20-89
Seattle, WA 98124-2207
USA
Fax: (206) 662-7812
Telex: 32-9430 Station 627
SITA: SEABO7X
Page 6 of 6
Operations Manual Bulletin No. ILF2-41(R5), Dated April 1, 1999 (continued)
Intentionally
Blank
CS3 - 2733 Page 1 of 2
Sect Name
Operations Manual Bulletin
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
波音747-441操作手册1(25)
