PART I-DESCRIPTIVE

	            conditioning system.  The inverter is energized by
	            either the generator or the battery.  If the inverter
	            fails, an amber light (15) at the top of the instrument
	            panel comes on.
	        (b) Two three-phase inverters, a main and a stand-by,
	            are powered by either the generator or the battery.
	            The main inverter supplies A.C. to the artificial
	            horizon, the gyro-magnetic compass and the fuel, oil
	            and hydraulic pressure indicating systems.  Should
	            the main inverter fail, an amber warning light (11)
	            shows and the stand-by inverter is engaged by mov-
	            ing the instrument power switch (113) from NORM.
	            to ALTERNATE and the amber light (11) should
	            go out. Should both the main and the stand-by inverters
	            fail, a red light (13) will come on and remain on.

	    (vii)Testing of warning lights
	         The warning lights fitted in the cockpit may be tested by
	         pressing them, when the light comes on.  Some of the
	         lights may be dimmed, if required, by turning the glass
	         covers in a clockwise direction.

	   17.   Hydraulic systems

	    (i)  The aircraft has two separate hydraulic systems.  One
	         operates the power controls and the other (called the
	         UTILITY) the remaining hydraulic services.  Each
	         system has a reservoir, an engine driven pump and
	         separate hydraulic pipelines.  In addition there is a
	         stand-by power controls system (called the ALTER-
	         NATE) operating from s separate reservoir and using
	         an electrically-driven pump as a source of power.  Pres-
	         sure in any of these three systems can be read on a single
	         hydraulic gauge (12) at the top of the instrument panel,
	         when the gauge selector (14) beside it is placed in the
	         appropriate position.  Each system has a working pres-
	         sure of 3,000 lb./sq. in.  The utility and normal power
	         control systems will not function till the engine is started
	         but the stand-by power control system will function if
	         electric power is available.  The stand-by power control
	         system should be checked periodically in flight.

	    (ii) Utility hydraulic system
	         This system operates the:-
	                  Air brakes
	                  Undercarriage
	                  Nosewheel steering and

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