PART IV - EMERGENCY HANDLING

                     the aircraft, and, providing that electrical
                     power is available and that the emergency
                     lowering system has not been operated, it
                     may be retracted after touch-down if neces-
                     sary.  With the undercarriage up, the aircraft
                     must be lowered gently on to the ground at
                     the normal speed; if the speed is too low a
                     wing drop is likely to occur, and if the speed
                     is too high the aircraft is prone to bounce,
                     the initial impact having a damaging effect
                     on the cockpit.
                     
                 2.  With the undercarriage down, the rate of
                     descent is high, and it increases rapidly as
                     speed is reduced below 180 knots.
                     
                 3.  For practice forced landings, a flap setting
AL1                  of 3023° and 4,5005,300 r.p.m. (min) will give a
                     rate of descent comparable with an engine-
                     off glide.
                     
    95.  Undercarriage and flaps emergency operation
                
         NOTE.-Both systems operate independently of their
               normal selectors.  When Mod. 428 is incor-
               porated both systems are isolated from the
               powered control hydraulic system.  Thus when
               either emergency system is operated the power
               controls will be unaffected, i.e., no jettisoning
               of hydraulic fluid will occur and the drills con-
               tained in (a) (iii) and (iv) and (b) are no longer
               necessary.
                
   (a) Undercarriage

        (i)  If the undercarriage fails to lock down by normal
             selection when both electric and hydraulic systems
             are serviceable repeated raising and lowering and the
             application of side-slip or G may have the desired
             effect.

        (ii) If all attempts to lower the undercarriage (or any
             unit of the undercarriage) by the normal system
             fail, the emergency system should be used.  How-
             ever, if electrical and hydraulic power is normal and

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