57-20-00
 ALL  ú ú 01 Page 2 ú Jun 10/88
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 WING LEADING EDGE - DESCRIPTION AND OPERATION
_____________________________________________
 1.  General (Fig. 1)_______
 A.  The leading edge structure is cantilevered forward from the front spar and consists of a series of flanged, stiffened ribs installed normal to the leading edge. The upper and lower leading edge skin panels are constructed of glass fabric honeycomb materials and finished with a static conditioner and conductive coating. The nose cap is aluminum. In the area where the Krueger and variable camber (leading edge) flaps are installed, the ribs are only partial ribs, and form the upper and forward portion of the leading edge structure. Tubular braces between the forward portion of the ribs and the front spar lower chord provide additional structural support. The leading edge flaps are supported by the leading edge structure and, when retracted, form a large portion of the lower forward exterior surface. Spanwise beams are located immediately aft of the flap trailing edges and serve to support the lower aft leading edge skin panels. Struts connecting the beam to the ribs provide additional rigidity. An aerodynamic seal is provided to seal the gap between the flap trailing edges and the beam when the flaps are in the retracted position (Ref 27-81-00).
 2.  Krueger Flap Area (Fig. 1)_________________
 A.  Three Krueger type flaps are supported by each wing leading edge structure and retract into the flap well in the lower forward portion of the leading edge inboard of the inboard nacelle. Four hinge fittings support each flap segment; each hinge fitting is attached to a flap support leading edge rib. The center two support ribs for each segment also serve as a flap actuator attachment point. Air loads generated during operation of the flaps are transferred through the leading edge ribs into the wing main frame. Flap mechanism components such as the drive unit and torque tube transmissions, are housed in the wing leading edge and are supported by the ribs and associated structure. The Krueger flaps are numbered, left to right, 11 through 16.
 3.  Variable Camber Flap Area (Fig. 1)_________________________
 A.  The 14 segments of the variable camber flaps, in each wing, are installed in the lower forward portion of the leading edge and retract into flap wells. Two sets of mechanical actuation linkages supporting each flap segment are attached to the forward portion of ribs installed on each side of the flap linkages. Other ribs are installed near the midpoint of each flap segment. During flap operation, air loads are transferred through the flap linkages and support ribs into the wing main frame. Flap mechanism components, including the drive units, rotary actuators, and torque tube drives, are supported by the leading edge structure. The variable camber flaps are numbered, left to right, 1E through 13 and 14 through 26E.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 57-21-00
 ALL  ú ú 01 Page 1 ú Oct 15/98
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

LEADING EDGE

A FRONT SPAR

VARIABLE CAMBER FLAP
SEE WING TIP
INBD

LEADING EDGE STRUCTURE (TYPICAL)

1
PARENTHESIS INDICATES RIGHT
WING LEADING EDGE FLAP

A
NUMBER.
Wing Leading Edge
Figure 1 (Sheet 1)

EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 57-21-00
 ALL  ú ú 01 Page 2 ú Feb 10/97
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
WING LE RIB DRIVE UNIT
HINGE FITTING (2 PLACES)
WING LE RIB
ACTUATION
LINKAGE

VARIABLE CAMBER FLAP ACTUATING LINKAGE
KRUEGER FLAP
KRUEGER FLAPS
B
PNEUMATIC DUCT (REF)
DRIVE UNIT
FOLDING NOSE
VARIABLE CAMBER FLAPS
C

Wing Leading Edge Figure 1 (Sheet 2)
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
　
中國航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊(cè) 機(jī)翼 WINGS(20)