Cessna 17273274 Pilot Operating Handbook page 133

SECTION 7
AIRPLANE & SYSTEMS DESCRIPTIONS
window outward, and hold it there. An opena.ble window is also available
for the right door, a.nd functions in the same manner as the left window. If
required, either window ma.y be opened at any speed up to 160 KIAS. The
cabin top windows (if installed), rear side windows, and rear windows are
of the fixed type and cannot be opened.
CONTROL LOCKS
A control lock is provided to lock the aileron and elevator control
surfaces to prevent damage to these systems by wind buffeting while the
airplane is parked. The lock consists of a shaped steel rod with a red metal
flag attached to it. The flag is labeled CONTROL LOCK, REMOVE
BEFORE STARTING ENGINE. To install the control lock, align the hole
in the top of the pilot's control wheel shaft with the hole in the top of the
shaft collar on the instrument panel a.nd insert the rod into the aligned
holes. Installation of the lock will secure the ailerons in a neutral position
and the elevators in a slightly trailing edge down position. Proper
installation of the lock will place the red flag over the ignition switch. In
areas where high or gusty winds occur, a control surface lock should be
installed over the vertical stabilizer a.nd rudder. The control lock and any
other type of locking device should be removed prior to starting the engine.
ENGINE
The airplane is powered by a horizontally-opposed, four-cylinder.
overhead-valve, air-cooled, ca.rbureted engine with a. wet sump oil system.
The engine is a Lycoming Model O-320-H2AD and is rated at 160 horsepow­
er a.t 2700 RPM. Major accessories include a starter and belt-driven
alternator mounted on the front of the engine, and dual magnetos and a
vacuum pump which are mounted on an accessory drive pad on the rear of
the engine. Provisions a.re also made for a full flow oil filter.
ENGINE CONTROLS
Engine power is controlled by a throttle located on the switch and
control panel above the control pedestal. The throttle operates in a
conventional manner; in the full forward position, the throttle is open, a.nd
in the full aft position, it is closed. A friction lock, which is a round knurled
disk, is located a.t the base of the throttle and is operated by rota.ting the
lock clockwise to increase friction or counterclockwise to decrease it.
The mixture control, mounted above the right corner of the control
pedestal, is a red knob with raised points around the circumference and is
equipped with a lock button in the end of the knob. The rich position is full
forward, and full aft is the idle cut-off position. For small adjustments, the
7-16
CESSNA
MODEL 172N
1 July 1979