Cessna 182 1978 - Bulkheads; Repair after Hard Landing; Firewall Damage; Engine Mount Support Cradle Damage

MODEL
182 &
T182
SERIES
SERVICE
MANUAL
Wrinkles
occurring
in open
areas which
disappear
18-66.
ENGINE
MOUNT.
when the rivets at the edge of the sheet are removed,
or a wrinkle which
is hand removable,
may often
be 18-67.
DESCRIPTION.
The mount
for the aircraft
repaired by the
addition of a 1/2 x 1/2
x .060 inch engine
is constructed of 4130
chrome-molybdenum
2024-T4 extruded angle,
riveted over the wrinkle
and steel tubing.
A truss structure,
fastened to the fire-
extended to within
1/16 to 1/18 inch of the
nearest wall
at four points. supports
a cradle arrangement.
structural members.
Rivet pattern
should be
identi-
This cradle arrangement
with
its supporting lugs,
cal to
existing manufactured seam at edge of sheet.
forms the base for rubber shock mounted
engine sup-
Negligible damage to stringers, formed skin flanges, ports.
bulkhead
channels, and
like parts is similar
to that
for the wing skin, given in paragraph
18-13. 18-68. GENERAL
CONSIDERATIONS. All welding
on the engine
mount must be of
the highest quality
18-60. REPAIRABLE DAMAGE.
Fuselage skin re- since the tendency
of vibration is to accentuate any
pairs may be accomplished
in the same manner as minor defect
present and cause fatigue cracks. En-
wing skin repairs outlined in paragraph 18-14. gine mount members are preferably repaired by using
Stringers, formed skin flanges, bulkhead channels
a larger diameter replacement
tube. telescoped over
and similar
parts may be repaired as shown in fig-
the stub of the original member using
fishmouth and
ure 18-5.
rosette
type welds. However,
reinforced 30-degree
scarf welds in place of the fishmouth welds are con-
18-61.
DAMAGE NECESSITATING
REPLACEMENT
sidered satisfactory
for engine mount
repair work.
OF PARTS. Fuselage
skin major repairs may be Refer
to Section 19 for engine mount painting.
accomplished
in the same
manner as the wing repairs
outlined in paragraph 18-15. Damaged fittings must 18-69. ENGINE MOUNT SUPPORT CRADLE DAM-
be replaced. Seat rails serve as structural parts of AGE. Minor damage such as a crack adjacent to an
the fuselage
and must be replaced if damaged.
engine attaching lug may be repaired
by rewelding
the cradle tube
and extending a gusset
past the dam-
18-62. BULKHEADS.
aged area. Extensively
damaged parts must
be re-
placed.
18-63. LANDING GEAR BULKHEADS. Since these
bulkheads are highly stressed members, irregularly
18-70. DAMAGE INVOLVING
ENGINE MOUNTING
formed to provide clearance for control
cables, fuel LUGS AND ENGINE MOUNT
TO FUSELAGE ATTACH-
lines, etc., the patch-type repairs will be, for the ING FITTINGS. Engine mounting lugs and engine
most part, impractical. Minor damage, consisting mount-to-fuselage attaching fittings should not be re-
of small nicks or scratches, may be repaired by paired but must be replaced.
dressing out the damaged area, or by replacement
of rivets. Any
other damage must be repaired by 18-71.
BAFFLES. Baffles ordinarily require
re-
replacing
the landing gear
support assembly
as an
placement
if damaged or cracked.
However.
small
aligned unit.
plate reinforcements
riveted
to the baffle will
often
prove satisfactory both to the strength and cooling
18-64. REPAIR
AFTER
HARD
LANDING.
Buckled
requirements
of the
unit.
skin or floorboards, and loose or sheared rivets in
the
area of the main
gear support
will give
evidence
18-72.
ENGINE
COWLING.
of damage to the structure from an extremely hard
landing.
When
such evidence
is present,
the entire
18-73.
REPAIR
OF COWLING
SKINS.
If extensively
support
structure
must be
examined,
and all support
damaged. complete
sections
of cowling
must be
re-
forgings
must be checked for cracks, using a dye
placed. Standard insert-type skin patches,
however,
penetrant
and proper magnification.
Bulkheads in
may be used if repair
parts are formed to
fit. Small
the damaged
area
must be checked
for alignment,
cracks
may be stop-drilled
and dents straightened
if
and deformation of the bulkhead webs must be deter- they are reinforced on the inner side with a doubler
mined
with the
aid of
a straightedge.
Damaged
sup-
of the
same
material.
port structure,
buckled floorboards
and skins,
and
18-74 RPA
OF REINFORCEMENT
ANGLES
damaged or questionable forgings must be replaced.
Cowl reinforcement angles, if damaged, must be
18-65.
FIREWALL DAMAGE.
Firewall sheets may
replaced. Due to
their small size they
are easier
be repaired by removing the damaged material (MIL- to replace than to repair.
S-5059) corrosion-resistant
(18-8)
steel. and splicing
in a new
section. The new
portion must be lapped
over the old
material, sealed with
Pro-Seal #700
(Coast Pro-Seal Co.,
Chemical Division,
2235 Be-
verly Blvd.. Los Angeles. California) compound, or
equivalent, and secure with steel (MS16535) rivets.
The heater valve, located in the right-hand side of the
firewall is secured with steel rivets. The remainder
of the firewall attaching
structure and bracketry
is
attached with aluminum
(MS20470D)
rivets.
18-5