Figure 4-21.Corrosion-prone point of air inlet duct.
ejection seats could become severely corroded if not
given adequate attention.
The likelihood that slight corrosion could make an
ejection seat inoperable must not be overlooked. The
MRCs for these seats require that every portion of the
seats be checked thoroughly for corrosion when they are
removed from the aircraft. Additional emphasis is
usually given to the ultrahigh-strength steel parts of
seats. As with all aircraft parts, corrosion could weaken
the structural soundness of a seat. Maintenance
personnel should give worn paint finishes and those
showing signs of superficial corrosion immediate
attention, as specified in the applicable MIM, because
other problems not yet visible may be present. They
should touch up cockpit fasteners with dull, black paint
to prevent cockpit glare. Refer to NAVAIR 01-1 A-509
for more information.
Intake and Exhaust Trail Areas
Airborne dirt and dust and bits of gravel from
runways constantly erode engine frontal areas and
cooling air vents. Rain erosion removes the protective
finish on intake and exhaust areas (fig. 4-21). In
addition, areas such as air intake ducts and cooler
radiator cores are not painted. Engine accessory
mounting bases usually have small areas of unpainted
magnesium or aluminum on the machined mounting
surfaces. With moist, salt-laden air constantly flowing
over these surfaces, they are prime sources of a
corrosive attack (fig. 4-22). When maintenance
Figure 4-22.Corrosion in air intake duct.