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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

FORWARD INBOARD STEP SILL ASSEMBLY
FORWARD OUTBOARD SILL ASSEMBLY
CASTER
RETRACTABLE INBOARD SIDE GUIDE
ROLLER
INBD
ROLLER
FWD
INBOARD SIDE GUIDE STOWAGE RELEASE RETRACTABLE
NOTE: FORWARD SILL ASSEMBLY
PLUNGER  OUTBOARD SIDE GUIDE  ____ 
OUTBOARD SIDE GUIDE  SHOWN, AFT SILL ASSEMBLY 
STOWAGE RELEASE PLUNGER  OPPOSITE. 

RETRACTABLE SIDE DOOR SILL ROLLER/CASTER RETRACTABLE
LATERAL GUIDE
AND GUIDE ASSEMBLY
CASTER
O  (2 LOCATIONS)
ROLLER (4 LOCATIONS)
LATERAL GUIDE STOWAGE LOCK PLUNGER RELEASE LEVER
CASTER
(EXAMPLE)
CASTER PANEL (EXAMPLE)
RETRACTABLE LATERAL GUIDE AND CASTER PANEL ASSEMBLY (EXAMPLE)
P
Main Deck Cargo Compartment Cargo Handling Equipment Figure 1 (Sheet 10)
C86001
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
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747-400
MAINTENANCE MANUAL

 2.  Caster Trays____________(Fig. 1)
 A.  Casters made up of parallel rollers in a swiveling turret are mounted between beam sections to form caster trays. Casters are used to support cargo units while in longitudinal and lateral transfer, as well as when parked. Caster trays are attached to the floor fittings with quarter-turn fasteners.
 B.  Each caster consists of three 1.5-inch steel, aluminum or nylon rollers, mounted in a turret which swivels on a sealed bearing. Spacing of casters and length of caster trays vary with location in the cargo compartment.
 3.  Roller Trays (Fig. 1)
____________
 A.  Roller trays are installed just outboard of the retractable center guide/restraints on each side of the cargo compartment. Each tray contains individually replaceable rollers installed 10-inches apart and attach to floor fittings with quarter-turn fasteners.
 4.  Lock/Stop Roller-Caster Trays_____________________________(Fig. 1)
 A.  Three rows of lock/stop roller-caster trays are installed along the entire length of the cargo compartment on each side of the airplane centerline. Locks and stops are intermittently spaced throughout the length of the trays to provide longitudinal and vertical restraint for the cargo units. Three locks and/or stops restrain the forward and aft ends of each cargo unit and may be relocated in 1-inch increments throughout the tray length for differing lengths of cargo units. Rollers and casters serve as part of the conveyor system and may be relocated in 1-inch increments throughout the length of the tray.
 B.  For further information on lock/stop roller-caster trays, refer to 25-58-00/001, Main Deck Cargo Restraining System.
 5.  Sill Roller Assemblies (Fig. 1)
______________________
 A.  The sill rollers are at the nose and side door cargo. The sill rollers move the cargo units in and out of the airplane. The sill assembly contains retractable i nboard and outboard guides, casters, rollers, and end locks.
 6.  Caster Panels (Fig. 1)
_____________
 A.  Casters made up of parallel rollers in a swiveling turret are mounted in panels located in the side door cargo transfer area to support cargo units while in longitudinal and lateral transfer, as well as when parked. The panels also contain retractable lateral guides located at the forward and aft sides of the side door cargo transfer area to aid in the alignment of cargo units. The caster panels are attached to floor fittings with quick-release fasteners.
 7.  Power Drive Units (Fig. 2)
_________________
 A.  The drive system equipment consists of floor mounted and tray mounted power drive units (PDUs) in the main deck compartment to move and steer cargo units laterally and longitudinally into parking positions.
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