Cessna 152 1979, Pilot Operating Handbook

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CESSNA SECTION 7
MODEL 152 AIRPLANE & SYSTEMS
DESCRIPTIONS
1 July 1978 7-27
CABIN HEATING, VENTILATING AND DEFROSTING SYSTEM
The temperature and volume of airflow into the cabin can be regulated by manipulation of the
push-pull CABIN HT and CABIN AIR control knobs (see figure 7-8).
Heated fresh air and outside air are blended in a cabin manifold just aft of the firewall by
adjustment of the heat and air controls; this air is then vented into the cabin from outlets in the
cabin manifold near the pilot's and passenger's feet. Windshield defrost air is also supplied by
a duct leading from the manifold.
For cabin ventilation, pull the CABIN AIR knob out. To raise the air temperature, pull the
CABIN HT knob out approximately 1/ 4 to 1/ 2 inch for a small amount of cabin heat.
Additional heat is available by pulling the knob out farther; maximum heat is available with the
CABIN HT knob pulled out and the CABIN AIR knob pushed full in. When no heat is desired in
the cabin, the CABIN HT knob is pushed full in.
Additional ventilation air may be obtained by opening the adjustable ventilators near the upper
left and right corners of the windshield.
PITOT-STATIC SYSTEM AND INSTRUMENTS
The pitot-static system supplies ram air pressure to the airspeed indicator and static pressure
to the airspeed indicator, rate-of-climb indicator and altimeter. The system is composed of
either an unheated or heated pitot tube mounted on the lower surface of the left wing, an
external static port on the lower left side of the forward fuselage, and the associated plumbing
necessary to connect the instruments to the sources.