PART V-OPERATING DATA

               Select the height at which maximum range is avail-
               able at that fuel state. The distance available in-
               cludes distance covered on the climb, but not on the
               descent. (Absolute maximum range is obtained by
               adding on the descent distance, provided that the
               let-down is commenced at that distance from the
               destination.)

               For short range flights inspect the sea level block
               and select the height at which the distance to be
               covered requires the least amount of fuel. This is
               the best altitude for the flight.
               
         (ii)  In-flight planning

               At any stage of a flight the available range may be
               ascertained by applying the fuel state to the level
               flight range in the particular altitude block.
               If an increase in range is required, or if a climb
               has to be made, the new available range may be
               obtained by entering the existing altitude block at
               the particular fuel state and moving vertically down-
               wards within the block until the new altitude is
               reached. Figures in heavy type indicate the best
               altitude for the maximum increase in range. Above
               these heights no further range increase is possible.
               If a descent is necessitated, the new range is shown
               by moving direct from the existing altitude level
               flight range for the particular fuel state to the new
               altitude level flight range.

     (c)  ANM per 100 lb./T.M.N./R.p.m. curves

          The graphs on pages 93 and 94 show the ANM per
          100 lb., for various altitudes, plotted against True Mach
          Number. Superimposed on the curves are dotted lines
          which show the approximate r.p.m. required for a given
          speed.

87