TM 55-1510-219-10 7-10.  RESERVE FUEL. Reserve Fuel is calculated for 45 minutes at Maximum Range   Power   @   1700   RPM.      Use   planned   cruise altitude  (22,000  feet),  forecasted  ISA  condition  (ISA  + 17°C),   and   estimated   weight   at   end   of   planned   trip (10,091  pounds).    (Since  the  lowest  weight  column  in the  tables  is  11,000  pounds,  assume  weight  at  the  end of  the  planned  trip  to  be  11,  000  pounds,  and  use  that fuel flow value for this example.) Enter  the  tables  for  MAXIMUM  RANGE  POWER @ 1700 RPM for ISA + 10°C and ISA +20°C at 11,000 Lbs and 22,000 feet, and read the total fuel flows: ISA +10°C  ...............................................468 Lbs/hr ISA +20°C ................................................484 Lbs/hr Then interpolate for the fuel flow at ISA + 17°C as follows:   Change   in   Fuel   Flow   =   484   468   =   16 Lbs/hr. Change in Temperature = (ISA +20°C) (ISA + 10 C) = 10°C. Rate  of  Change  in  Fuel  Flow  =  Change  in  Fuel Flow + Change in Temperature. Rate   of   Change   in   Fuel   Flow   =   (16   Lbs/hr)   + (10°C). Rate of Change in Fuel Flow = 1.6 Lbs/hr increase per 1°C increase. Temperature  increase  from  ISA  +  10°C   to   ISA +17°C = 7°C. Total Change in Fuel Flow = 7 X 1.6 Lbs/hr = 11.2 Lbs/hr. Total Fuel Flow = (ISA +10°C Fuel Flow) + (Total Change in Fuel Flow). Total Fuel Flow = (468) + (11.2) = 479.2 Lbs/ hr. Reserve Fuel = 45 minutes X Total Fuel Flow. Reserve Fuel = (0.75) X (479.2 Lbs/hr) = 359.4 = 360 lbs/hr. Total   Fuel   Requirement   =   1999   +360   =   2359 pounds. 7-11.  ZERO FUEL WEIGHT LIMITATION. For  this  example,  the  following  conditions  were assumed: Ramp Weight  ................................... 12,090 pounds Weight of Usable Fuel Onboard  ..........2359 Pounds Zero  Fuel  Weight  =  Ramp  Weight  -  Weight  of Usable Fuel Onboard Zero   Fuel   Weight   =   (12,090)   (2359)   =   9731 pounds Maximum     zero     fuel     weight     limitation     (from Chapter 5) = 11,500 pounds. Maximum   Zero   Fuel   Weight   Limitation   has   not been exceeded. Anytime    the    Zero    Fuel    Weight    exceeds    the Maximum  Zero  Fuel  Weight  Limit,  the  excess  must  be off-loaded from PAYLOAD.  If desired, additional FUEL ONLY may then be added until the ramp weight equals the Maximum Ramp Weight Limit of 14,290 Lbs. 7-12.  LANDING INFORMATION. The    estimated    Landing    Weight    is    determined    by subtracting the fuel required for the trip from the Ramp Weight: Ramp Weight .......................................... 12,090 Lbs Fuel Required for Total Trip  ................ 1999 pounds Landing Weight (12,090 - 1999) . ...... 10,091 pounds Enter the NORMAL LANDING DISTANCE WITHOUT   PROPELLER   REVERSING   FLAPS   100% Graph at 32°C, 4502 feet, 10,091 pounds, and 10 knots head wind component: Ground Roll............................................... 1725 feet Total Distance Over 50-foot Roll  .............. 1725 feet Total Distance Over 50-foot Obstacle ....... 3060 feet Approach Speed  ...................................... 100 knots Enter  the  CLIMB  -  BALKED  LANDING  Graph  at 32°C, 4502 feet, and 10,091 pounds: Rate of Climb  .........................................1550 ft/min Climb Gradient .............................................. 12.5% 7-13.      COMMENTS   PERTINENT   TO   THE   USE   OF PERFORMANCE GRAPHS. a. In  addition  to  presenting  the  answer  for  a particular set of conditions, the example on a graph also presents  the  order  in  which  the  various  scales  on  the graph should be used.  For instance, if the first item in the example is FAT, then enter the graph at the existing FAT. b. The reference lines indicate where to begin following the guidelines.  Always project to the reference line  first,  then  follow  the  guidelines  to  the  next  known item by maintaining the same PROPORTIONAL 7-5