Powerplant And Propeller; General Description; Air Cleaning System; Powerplant - Thrush Aircraft S2RHG-T65 TURBO THRUSH Maintenance Manual

THRUSH AIRCRAFT, INC – MODEL S2RHG-T65 TURBO THRUSH
AIRCRAFT MAINTENANCE MANUAL

POWERPLANT AND PROPELLER

GENERAL DESCRIPTION

The Turbo Thrush S2RHG-T65 agricultural airplane utilizes a Pratt & Whitney Aircraft
Canada PT6A-45A, -45B, -45R, PT6A-60AG, or PT6A-65AG, -65AR, or -65B turboprop
gas turbine engine. The dual cockpit version is approved with the PT6A-60AG engine
only at this time.

AIR CLEANING SYSTEM

The prime difference between the agricultural application and a normal installation is the
air cleaning system incorporated in the engine air intake system. The lower cowl forms
the inlet to the engine. The air filter panel is a K & N cleanable barrier filter. It provides
high efficiency, maximum reliability, long service life and low overall cost.
The barrier filter unit is made of a cotton mesh with a light coat of K&N special red oil to
assist in collecting dust. The filter can be removed, cleaned and reserviced I/A/W
cleaning instructions from K & N P/N 99-5000 (aerosol) or P/N 99-5050 Recharger filter
care service kit, obtained locally.

POWERPLANT

DESCRIPTION AND OPERATION

The PT6A-45A, -45B, -45R, PT6A-60AG, and PT6A-65AG, -65AR, -65B (See Figure 4-
0) series power plant is a lightweight free turbine engine. The engine utilizes two
independent turbine sections: one driving the compressor in the gas generator section
and the second driving the propeller shaft through a reduction gearbox. The engine is
self-sufficient, since its gas generator driven oil system provides lubrication for all areas
of the engine, pressure for the torque meter and power for propeller pitch control.
Inlet air enters the engine through an annular plenum chamber, formed by the
compressor inlet case where it is directed forward to the compressor. The PT6A-60AG
and PT6A-45A, -45B, -45R compressor consists of three axial stages combined with a
single centrifugal stage, assembled as an integral unit. PT6A-65AG, -65AR, 65B has
four axial stages combined with a single centrifugal stage, assembled as an integral
unit.
The engine is equipped with a wash ring at the compressor air inlet screen. A line
running from this wash ring to a port on the outside of the cowling gives the capability to
cleanse the compressor section without engine cowling removal.
A row of stator vanes, located between each stage of compression, diffuses the air,
raises its static pressure and directs it to the next stage of compression. The
compressed air passes through diffuser tubes, which turn the air through ninety degrees
in direction and convert velocity to static pressure. The diffused air then passes through
straightening vanes to the annulus surrounding the combustion chamber liner assembly.
The combustion chamber liner is an annular, heat resistant alloy; domed at the front end
where it is supported inside the gas generator case by the 14 fuel manifold adapter
sheaths and both igniters. The rear end of the combustion chamber is open and is
supported by the large and small exit ducts. The liner assembly has perforations of
4-3
Effective: 9/16/05