PART IV-EMERGENCY HANDLING

     (c)  If complete electrical failure occurs control of the variable
          incidence tailplane is impossible. It is important there-
          fore, before batteries are fully discharged, to reduce
          I.A.S., and set the tailplane to approximately -1°
          incidence which will give a compromise of trim for return
          flight and landing conditions.


     84.  Hydraulic system failure (see para. 66(c)(ii))

     (a)  The only indication of failure of one hydraulic pump is a
          reduced rate of operation of the undercarriage. Warning
          of complete hydraulic pressure failure is given immedi-
          ately by an audible warning signal over the pilot's head
          set.

     (b)  If complete hydraulic failure occurs, reduce speed to
          below 280 knots or 0.8M and select Manual control.
          Automatic reversion to manual will occur in any event
          when the accumulators are exhausted if Manual control
          is not selected.

     (c)  Continuous and rapid use of the airbrakes at low r.p.m.
          may cause intermittent warning signals to be given, but
          should these signals he given during normal use of the
          airbrakes a partial hydraulic failure must be suspected.
          A careful watch should be maintained on the hydraulic
          accumulator gauges and the aircraft returned to base.

     (d)  The emergency handling of the undercarriage, flap,
          airbrakes and flying controls is dealt with under these
          respective headings.

     85.  Emergency operation of the powered controls

          NOTE.-If complete hydraulic failure occurs the two
                accumulators for the ailerons and elevator will
                last for sufficient time to regain straight and level
                flight at reduced speed.

     (a)  Actions in the event of complete hydraulic failure, engine
          under power or windmilling:-

          Reduce speed below 280 knots or 0.8M and select aileron
          and elevator Power OFF. Do not use the airbrakes to
          reduce speed as should the accumulators become
          exhausted it will be impossible to retract them.

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