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MAINTENANCE MANUAL
LOWER
WING POPPET SKIN (REF)
B-B
Fuel Sump Drain Valves
Figure 3 (Sheet 2)
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MAINTENANCE MANUAL
BAFFLE CHECK VALVE BAFFLE CHECK VALVE BAFFLE CHECK VALVE
(7 PLACES) (17 PLACES) (5 PLACES AFT OF MIDSPAR)
STA 294.62 STA 724.50 STA 807.00
SEE
SEE
SEE
Baffle Check Valves
Figure 4
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MAINTENANCE MANUAL
OVERWING FILL PORT SEE A
FILLER CAP
LANYARD PORT FILLER
UPPER WING SKIN
A
Overwing Fill Port and Cap Figure 5
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Center Wing Tank Purge Door
Figure 6
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(2)
Spar webs, chords, and rib end attachment assemblies permit fillet sealing on the tank side. All fillets are on the pressure side and are located at areas of minimum deflection. Bolts or lockbolts are used in high load areas and are sealed with seal caps and filleting materials.
(3)
Molded rubber seals are used to seal fuel tank access doors. O-rings are used to seal removable plumbing fittings, primary tension bolts, and fuel system components which penetrate the fuel tank walls.
(4)
The center wing tank has a secondary fuel barrier sealant applied to its upper exterior surface and to the forward surface of the center wing tank front spar.
B.
Definition of Sealing Terms
(1)
ABSOLUTE SEAL -- A level of sealing which requires that all seams, joggles, slots, holes, and fasteners that pass through the seal plane be sealed.
(2)
CAULKING -- A process of plugging a hole or channel with fiberglass cloth impregnated with sealant.
(3)
BACKUP SEAL -- A secondary seal which offers support to a primary seal.
(4)
BASE COMPOUND -- The major component of a sealing material used in conjunction with corresponding curing compound to produce a fuel-resistant sealant.
(5)
CURING COMPOUND -- Internal curing agent for sealants.
(6)
FAYING SURFACE SEAL -- A seal installed by sandwiching of sealant between mating surfaces of assemblies.
(7)
FIRST FILLET -- A small bead of sealant applied over the precoat to ensure complete contact and to cover seams or joints.
(8)
FINAL FILLET -- A bead of sealant applied on the first fillet to produce a full bodied fillet.
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