PART V-EMERGENCY HANDLING


        80. Relighting

        (a)  The engine is more likely to relight below 25,000 ft.
             Airspeed during the relight should be 170-180 knots,
             otherwise the engine tends to overheat, particularly at
             high altitudes. If because of weather it is desirable to
             attempt a relight above 25,000 ft., airspeed during the
             attempt should be 220 knots.

         (b) Check:-

             Throttle				SHUT.
             H.P. cock				SHUT.
             Non-essential electrical ser-	Off.
               vices
             Isolating switch			ON. (If the flame-out is
				  		  due to a defective fuel
						  system).
             Booster pump			ON.

        (c)  Press the relight button and OPEN the H.P. cock simul-
             taneously keeping the relight button pressed. A relight
             should occur within 20 seconds.

        (d)  If height permits, dive aircraft when relight occurs to
             reduce the risk of high j.p.t. and to help increase r.p.m.

        (e)  When relit open the throttle carefully to avoid over-
             heating.
              

        81.  Failure to relight

        (a)  If the engine fails to relight SHUT the H.P. cock and
             allow 60 seconds before attempting a further relight to
             enable the engine to dry out. In an emergency the time
             may be reduced to 30 seconds.

        (b)  If a number of unsuccessful attempts are made, relighting
             may be attempted with the throttle fully OPEN, closing
             it immediately relight occurs.

        (c)  The most likely cause of failure to relight will be in-
             sufficient voltage. Therefore switch off all non-essential
             electrical services with the exception of the booster pump
             before attempting to relight.

60