HEADQUARTERS OH-58A, Technical Manual, Page: 60 / 292

TM 55-1520-228-10
2-18 Change 11
SECTION II. EMERGENCY EQUIPMENT
2-7. FIRST AID KIT.
An aeronautical type first aid kit is located on the right
side of the center support column.
2-8. FIRE EXTINGUISHER.
A portable fire extinguisher is mounted in a bracket lo-
cated on the right side of the center support column
(figure 9-1).
SECTION III. ENGINES AND RELATED SYSTEMS
2-9. ENGINE.
The OH-58A/C helicopter is equipped with a T63-A-720
turbine engine (figure 2-11). The engine is designed for
low fuel consumption, light weight, minimum size, maxi-
mum reliability and ease of maintenance. The engine is
installed aft of the mast and the passenger compart-
ment. The engine cowl aft of the engine air inlet is re-
movable as a single unit or the hinged section the length
of the engine on either side may be opened individually.
The aft fairing covers the engine oil cooler, provides tail
rotor driveshaft access and provides air intake for the
engine oil cooler. The major engine components are as
follows:
a. Compressor. Air enters the engine through the
particle separator to the compressor inlet and is com-
pressed by six axial compressor stages and one centrif-
ugal stage. The particle separator removes dirt and
other contaminates from the incoming air and ejects the
dirt out ducts on either side of the fairing. This allows
cleaned air to enter the engine compressor section. The
compressed air is discharged through the scroll type
diffuser into two external ducts which convey the air to
the combustion section.
b. Combustion Section. The combustion section
consists of the outer combustion case and combustion
liner. A spark igniter and fuel nozzle are mounted in the
aft end of the outer combustion case.
c. Turbine. The turbine consists of a gas producer
turbine support, a power turbine support, a turbine and
exhaust collector support, a gas producer turbine rotor,
and power turbine rotor. The turbine is mounted be-
tween the combustion section and the power and acces-
sory gearbox. The two-stage gas producer turbine
drives the compressor and accessory gear train. Gas
discharged from the gas producer turbine drives the
two-stage power turbine which furnishes the output
power of the engine. The gas from the power turbine
discharges in an upward direction through twin ducts in
the turbine and exhaust collector support.
d. Power and Accessories Gearbox. The main
power and accessory drive gear train are enclosed in a
single gear case. The gear case serves as a structural
support of the engine. All engine components including
engine mounted accessories are attached to the case.
A two-stage helical and spur gear set is used to reduce
rotational speed from the power turbine to the output
drive spline. Accessories driven by the power turbine
gear train (N2) are the power turbine (N2) tachometer-
generator, power turbine governor, and torquemeter.
The gas producer (N1) drives the compressor, and
through an associated gear train drives the fuel pump,
gas producer (N1) tachometer-generator, gas producer
fuel control, starter-generator, and engine oil pump.