FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 9. Aircraft Systems and Components | 1. Inspection and Maintenance of Landing Gear | 9-8. Floats and Skis
9/27/01
AC 43.13-1B CHG 1
ing of components and related tubing or wir-
ing. This could interfere with the travel of the
gear door actuating mechanisms.
e. Wheels. Inspect the wheels periodi-
cally for cracks, corrosion, dents, distortion,
and faulty bearings in accordance with the
manufacturer’s service information. In split-
type wheels, recondition bolt holes which have
become elongated due to some play in the
through-bolt, by the use of inserts or other
FAA-approved means. Pay particular attention
to the condition of the through-bolts and nuts.
Carefully inspect the wheels used with tubeless
tires for damage to the wheel flange and for
proper sealing of the valve. The sealing ring
used between the wheel halves should be free
of damage and deformation. When bolting
wheel halves together, tighten the nuts to the
proper torque value. Periodically accomplish
an inspection to ensure the nuts are tight and
that there is no movement between the two
halves of the wheel. Maintain grease retaining
felts in the wheel assembly in a soft, absorbent
condition. If any have become hardened, wash
them with a petroleum-base cleaning agent; if
this fails to soften them, they should be re-
placed.
(1) Corrosion of wheels. Remove all
corrosion from the wheel half, and inspect it to
ensure that the wheel halves are serviceable.
Apply corrosion prevention treatments as ap-
plicable. Prime with a zinc chromate primer or
equivalent, and apply at least two finish coats.
(2) Dented or distorted wheels. Re-
place wheels which wobble excessively due to
deformation resulting from a severe side-load
impact. In questionable cases, consult the lo-
cal representative of the FAA concerning the
airworthiness of the wheels. Minor dents do
not affect the serviceability of a wheel.
(3) Wheel bearings. When inspecting
wheel bearings for condition, replace damaged
or excessively worn parts. Maintain bearings
and races as matched sets. Pack bearings only
with the grease type called for in the manu-
facturer’s maintenance manual prior to their
installation. Avoid pre-loading the wheel
bearing when installing it on the aircraft by
tightening the axle nut just enough to prevent
wheel drag or side play.
f. Brakes. Disassemble and inspect the
brakes periodically and examine the parts for
wear, cracks, warpage, corrosion, elongated
holes, etc. Discolored brake disks are an indi-
cation of overheated brakes and should be re-
placed. If any of these or other faults are indi-
cated, repair, recondition, or replace the af-
fected parts in accordance with the manufac-
turer’s recommendations.
g. Hydraulic Brakes. For proper mainte-
nance, periodically inspect the entire hydraulic
system from the reservoir to the brakes.
Maintain the fluid at the recommended level
with proper brake fluid. When air is present in
the brake system, bleed in accordance with the
manufacturer’s instructions. Replace flexible
hydraulic hoses which have deteriorated due to
long periods of service and replace hydraulic
piston seals when there is evidence of leakage.
h. Micro-Switches. Inspect micro-
switches for security of attachment, cleanli-
ness, general condition, and proper operation.
Check the associated wiring for chafing,
proper routing, and to determine that protec-
tive covers are installed on wiring terminals, if
required. Check the condition of the rubber
dust boots which protect the micro-switch
plungers from dirt and corrosion.
9-8. FLOATS AND SKIS. Aircraft oper-
ated from water may be provided with either a
single float or a double float, depending upon
the design and construction; however, if an
aircraft is an amphibian, it has a hull for flota-
tion and then may need only wingtip floats.
Par 9-7
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