Cessna 17273274 Pilot Operating Handbook page 120

CESSNA
MODEL 172N
INTRODUCTION
This section provides description and operation of the airplane and its
systems. Some equipment described herein is optional and may not be
installed in the airplane. Refer to Section 9, Supplements, for details of
other optional systems and equipment.
AIRFRAME
The airplane is an all-metal, four-place, high-wing, single-engine
airplane equipped with tricycle landing gear and designed for general
utility purposes.
The construction of the fuselage is a conventional formed sheet metal
bulkhead, stringer, and skin design referred to as semimonocoque. Major
items of structure are the front and rear carry'..through spars to which the
wings are attached, a bulkhead and forgings for main landing gear
attachment at the base of the rear door posts, and a. bulkhead with attach
fittings at the base of the forward door posts for the lower attachment of the
wing struts. Four engine mount stringers are also attached to the forward
door posts and extend forward to the firewall.
The externally braced wings, containing the fuel tanks, are con­
structed of a front and rear spar with formed sheet metal ribs, doublers, and
stringers. The entire structure is covered with aluminum skin. The front
spars are equipped with wing-to-fuselage and wing-to-strut attach fit­
tings. The a.ft spa.rs a.re equipped with wing-to-fuselage attach fittings, and
a.re partial-span spars. Conventional hinged ailerons and single-slot type
flaps are attached to the trailing edge of the wings. The ailerons are
constructed of a forward spar containing balance weights, formed sheet
metal ribs and "V" type corrugated aluminum skin joined together at the
trailing edge. The flaps are constructed basically the same as the ailerons,
with the exception of the balance weights and the addition of a formed sheet
metal lea.ding edge section.
The empenna.ge (tail assembly) consists of a. conventional vertical
stabilizer. rudder, horizontal stabilizer, and elevator. The vertical stabiliz­
er consists of a spar, formed sheet metal ribs and reinforcements, a wrap­
around skin panel, formed leading edge skin and a dorsal. The rudder is
constructed of a formed lea.ding edge skin containing hinge ha.Ives, a
center wrap-around skin panel. ribs, an aft wrap-around skin panel which
is joined at the trailing edge of the rudder by a filler strip, and a ground
adjustable trim tab at the base of the trailing edge. The top of the rudder
incorporates a lea.ding edge extension which contains a balance weight.
1 July 1979
AIRPLANE & SYSTEMS DESCRIPTIONS
SECTION 7
7-3