Cessna 172 Maintenance Manual page 120

1. General
A. Description of Wing Assemblies:
(1) The wing assemblies are a semicantilever type, employing semimonocoque type of structure.
(2) The internal structure consists of a built-up front spar, a formed inboard front fuel spar, a rear
spar, and a formed auxiliary spar assembly in the aileron attach area.
(3) Ribs are formed sheet metal, and consist of nose, intermediate and trailing edge assemblies.
(4) On the 172 series airplanes, stressed skin is riveted to the rib and spar assemblies to complete
the rigid structure. On 182 and 206 series airplanes, the skin is bonded to the leading edge ribs
and riveted at other locations.
The inboard section of the wing is sealed to form an integral fuel cell. The sealed area runs from
(5)
the wing root outboard toward the strut attach; and from the front fuel spar to the rear spar.
NOTE:
(6) Access openings (hand holes with removable cover plates) are located in the wing These
openings afford access to flap and aileron bellcranks and control systems, the flap actuator
in the left hand wing, electrical wiring and wiring disconnect points, the wing portion of the
ventilation system, strut attach fittings, and the inside of the fuel cell.
B. Refer to applicable Maintenance Manual, Chapter 6, Dimensions and Areas, for wing station
diagrams.
If questions arise concerning approved repairs, or for repairs not shown in this section, contact Cessna
C.
Propeller Aircraft Product Support, Box 7706, Wichita, KS 67277. (316) 517-5800, Facsimile (316)
942-9006.
2. Tools, Equipment and Materials
A. Refer to Figure 1 for an illustration of wing and fuselage support stands which may by fabricated locally
and used during structural repair.
3. Installation of Access Holes
NOTE: In some instances, it may be advantageous to create access holes in the wing skin to facilitate
wing repair. Refer to the following steps and Figure 2 for an illustration of access holes.
WARNING: The following procedures are not applicable to the integral fuel cell
skins.
A. Precautions and Notes.
Add the minimum number of access holes necessary.
(1)
(2) Any circular or rectangular access hole which is used with approved optional equipment
installations may be added in lieu of the access hole illustrated.
(3) Do not add access holes at outboard end of wing: remove wing tip instead.
(4) Locate new access holes near the center of a bay (spanwise).
(5) Locate new access holes forward of the front spars as close to the front spar as practical.
(6) Locate new access holes aft of the front spar between the first and second stringers aft of the
spar. When installing the doubler, rotate it so the two straight edges are closest to the stringers.
(7) Alternate bays, with new access holes staggered forward and aft of the front spar, are preferable.
A maximum of five new access holes in each wing is permissible. If more are required, contact
(8)
Cessna Propeller Aircraft Product Support.
B. Access Hole Installation. (Refer to Figure 2)
(1) Establish exact location for inspection cover and inscribe centerlines.
(2) Determine position of doubler on wing skin and center over centerlines. Mark the ten rivet hole
locations and drill to size shown.
CESSNA AIRCRAFT COMPANY
SINGLE ENGINE
STRUCTURAL REPAIR MANUAL
WINGS - GENERAL
On the 172 series airplanes, the fuel closeout rib is located approximately 7 inches
outboard from the wing root.
© Cessna Aircraft Company
57-00-00
Page 1
Jun 1/2005