PART 1II-HANDLING

               push-force is required; pitching, sometimes accom-
               panied by slight snaking, may occur as the speed
               approaches 0.82M.  On some aircraft, a nose-down
               change of trim me be felt at this speed but, in any case,
               all control forces are very high and wing dropping
               may occur.  The application of positive G will produce
               these effects at lower mach numbers.

         (ii)  Severe vibration may be experienced on some aircraft
               below the mach number limitation.  Should this hap-
               pen, no attempt is to be made to fly at a higher mach
               number.  If the mach number limitation of 0.78M is
               inadvertently exceeded in a diving turn, violent wing
               drop and complete loss of control may occur, particu-
               larly if high positive G is applied. The ensuing dive or
               spiral is likely to be very steep; buffeting and high
               stick loads will be experienced and a great loss of
               height is inevitable.

         (iii) When manoeuvring at high mach numbers at or just
               above 20,000 feet particularly care is needed.
               
         (iv)  Below 20,000 feet, the elevator trimmer may be used
               to counteract the strong nose-up trim change, up to
               the mach number limitation of 0.76M, after which it
               must not be used.  At speeds in excess of 0.76M, the
               push force required makes it difficult to hold the air-
               craft in a dive.  The aileron forces are very high on
               aircraft fitted with geared tabs but rather less when
               spring tabs are used.

    (c)  Recovery from high-speed dives

         Select airbrakes out, close the throttles and gently ease the
         aircraft out of the dive; application of high positive G may
         delay the recovery. If the aircraft is out of control in a dive
         or spiral the controls will become effective as height is lost
         and mach number reduced; while in this out-of-control
         condition, it is particularly important to avoid high posi-
         tive G until the mach number is reduced, because its appli-
         cation will nullify the beneficial effects of reducing mach
         numbers and prolong the uncontrollable dive.  If the aircraft
         is inverted, recovery should be made by rolling rather than
         pulling through.

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