Mahindra GIPPSAERO GA8-TC 320, Operating Handbook

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Section 7
Aircraft & Systems
Model GA8-TC 320 Description
Page 7-6 5 Feb 2009 C01-01-08
Engine Controls Engine power is controlled by a throttle located in a throttle quadrant on the
centre console to the right of the pilot. It is readily identified by a smooth black cylindrical knob.
The throttle operates in the conventional sense in that when fully forward the throttle is full open,
and in the fully aft position, the throttle is closed. Should the mechanical linkage from the throttle
lever fail, the throttle shaft is spring loaded to return the throttle control to at least 75% of the
open position.
The propeller control is located on the throttle quadrant to the right of and on a shorter arm than
the throttle control. It is fitted with a blue knob with lateral grooves for identification. The full fine,
takeoff position is fully forward and the coarse position is fully aft. Should the mechanical linkage
from the propeller pitch lever fail, the governor is spring loaded to move to the full fine position.
The mixture control is located on the throttle quadrant to the right of the propeller control. It
is fitted with a red knob with raised points around the circumference for identification. The
full rich position is fully forward, and fully aft is idle cut off. Should the mechanical linkage
from the mixture lever fail, the mixture control is spring loaded to return the mixture control to
at least 75% of the rich position.
The cowl flap lever is located on the throttle quadrant below the mixture control. The lever
allows for the opening and closing of the engine cowl flap used in managing engine cooling. The
lever is spring loaded laterally and can be locked in four different detent positions as required.
Should the mechanical linkage from the cowl flap lever fail, the cowl flap will float in the airsteam,
dropping to the fully open position as the airspeed decreases.
The alternate air control is a push-pull control located beneath the throttle quadrant. With
the control pushed fully forward (in), cold filtered air is selected. Fully aft (out) selects warm
unfiltered air from within the engine compartment.
Engine Instruments Engine operation is monitored by a tachometer, manifold pressure gauge,
fuel pressure and fuel flow gauges, oil pressure and oil temperature gauges, a cylinder head
temperature gauge and a turbine inlet temperature gauge. These instruments are located in
the instrument panel in front of the pilot and are marked with green arcs to indicate the normal
operating range, yellow arcs to indicate precautionary ranges and red lines at the maximum/
minimum allowable limits. These limits and gauge markings are also given in Section 2 of this
manual.
Engine Oil System
Oil for engine lubrication is supplied from a sump at the bottom of the
engine. The oil capacity of the engine is 11.4 litres (12 US quarts). Oil is drawn from the sump
through an oil suction strainer screen into the engine driven oil pump. Oil passes from the pump
to a thermostatically controlled bypass valve. If the oil is cold, the bypass valve allows the oil to
bypass the oil cooler and flow directly to the filter. If the oil is hot, the bypass valve routes the oil
from the accessory case through flexible hoses to the oil cooler. On returning to the accessory
case, the oil passes through the full flow replaceable element oil filter. The filtered oil then
enters a pressure relief valve that regulates the engine oil pressure by allowing excessive oil
to return to the sump, while the remaining oil under pressure is circulated to the various engine
components for lubrication. Residual oil returns to the sump by gravity flow.
An oil filler cap/dipstick is located on the top of the engine and is accessible through an access
door in the engine cowling. The dipstick is calibrated in US quarts. To minimise possible loss
01 Aug 2011