PART I-DESCRIPTIVE

                 for adjusting trim if the normal trimming switch fails.
                 One switch (65) is marked OFF, NORMAL, NOSE-UP
                 and NOSE-DOWN and the other (67) is marked OFF-
                 NORMAL, LEFT wing down and RIGHT wing down.
                 In each case the last two positions are spring-loaded.
                 When a switch is at NORMAL the thumb switch on the
                 control column can be used for trimming in that plane,
                 and when the switch is at OFF both the normal and stand-
                 by trimming circuits are inoperative. Holding a switch in
                 either of the spring-loaded positions adjusts the trim
                 accordingly.

	    (iii)The rudder trimming tab is operated electrically by a
                 switch (66) on the left aft console and an amber light(19)
                 is provided on the instrument panel to indicate when the
                 rudder trim tab is in neutral. To position the tab neutral
                 the switch is held in either the RIGHT or LEFT position
                 until the light comes on, and is then instantly released.
                 The light will then go out.

	    (iv) This light also indicates correct lateral and longitudinal
                 trim for take-off.  With the stand-by lateral trim switch
                 at NORMAL, the thumb switch on the control column is
                 operated sideways until the light comes on.  When the
                 switch is released the light goes out. Then with the longi-
                 tudinal stand-by switch at NORMAL, the thumb switch
                 is operated fore and aft until the light comes on.  When
                 the switch is released the light goes out. The aircraft is
                 then trimmed for take-off.

	    19.  Undercarriage control

	     (i) Normal operation
	         The undercarriage is hydraulically-operated and elec-
	         trically-controlled by a handle (1) at the left of the
	         instrument panel.  The handle has two positions only
	         UP and DOWN.  When the undercarriage is locked down
	         with the weight of the aircraft on the oleos, a ground
	         safety switch prevents retraction if the control handle is
	         inadvertently moved to UP.  The undercarriage fairing
	         doors will open, however, and thus indicate the incorrect
	         setting on the handle.

	     (ii)Emergency lowering
	         When the undercarriage emergency release (129) at the
	         bottom of the centre pedestal is pulled all the way out
	         and held, the main wheels and all the fairing doors are
	         mechanically unlocked, and the selector valves positioned
	         for lowering the undercarriage.  If the electrical system

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