Piper Navajo PA-31 Service Manual page 19

PIPER NAVAJO SERVICE MANUAL
1-7. FLIGHT CONTROLS. The flight controls are conventional, consisting of dual control wheels that
operate the ailerons and elevator, and dual foot pedals that operate the rudder. The trim tabs for each
control are operated by wheels or knobs located in the control pedestal.
1-8. HYDRAULIC SYSTEM. Two separate hydraulic systems are incorporated in the airplane. The main
system incorporates a hydraulic Power Pack that operates the landing gear and inboard main gear door
actuating cylinders. The second system operates the airplane's brake system.
1-9. LANDING GEAR. The tricycle landing gear system is hydraulically operated and fully retractable
with doors that completely cover the gear when retracted. The gears are air-oil type units.
1-10 ENGINES AND PROPELLERS.
The airplane is powered by two Avco-Lycoming six cylinder, direct
drive, wet sump, horizontally opposed. fuel injected engines. The propellers are Hartzell full feathering.
constant speed units controlled by a governor mounted on each engine. Refer to Section II. Table 11-1. for all
engine and propeller leading particulars.
1-1 1. FUEL SYSTEM. The fuel system consists of four rubber-type cells located in the wings with a total
fuel capacity of 192 U.S. gallons. Optional 27 gallon Nacelle fuel cells are available for the 31-325.
Incorporated in the system are fuel filters, electric auxiliary fuel pumps, engine driven pumps and a cross feed
system.
1-12. INSTRUMENTS. Provisions for the instrument installation includes panels for engine instruments
and advance flight instruments, as well as space for an optional second set of flight instruments for the
co-pilot. The panel is shock mounted to minimize vibration to the instruments.
1-13. ELECTRONIC EQUIPMENT. Provision for electronic equipment includes various combinations of
radio installations, Auto-Pilot and radar.
1-14. HEATING AND VENTILATING SYSTEM. Heated air for the cabin and defroster is obtained from
a 35,000 B.T.U. Janitrol heater installed in the nose section. Fresh air for the cabin interior is obtained
from two individual sources; one from an intake in the nose section and the other from a scoop located in
the dorsal fin.
Revised: 11/15/82
INTRODUCTION
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