AFI 11-2C-130v3 - BITS

AFI11-2C-130V3 23 APRIL 2012 153
11.12.1.3. TERMINAL FUEL FLOW.
11.12.1.4. CURRENT FUEL FLOW.
11.12.1.5. AVG FUEL FLOW. Calculate by adding terminal fuel flow to current fuel
flow and dividing the sum by 2.
11.12.1.6. FUEL REM. Fuel quantity at time of calculation. In the interest of safety, use
the lower of the calculated or gauge fuels.
11.12.1.7. O/H FUEL. Required overhead fuel (item 12 of the fuel plan).
11.12.1.8. DIFF. Subtract O/H Fuel from FUEL REM.
11.12.1.9. FUEL ETE. Calculate using formula in paragraph 11.12.2.3.
11.12.1.10. ETE DEST. Subtract TIME from ETA DEST.
11.12.1.11. EXT TIME. Subtract ETE DEST from FUEL ETE. Report this value to the
pilot. If this is a negative value, check the computation and values for errors. If they are
correct, evaluate your destination options.
11.12.2. Use the following formulas to accomplish in-flight fuel management:
11.12.2.1. [(Terminal fuel flow + Present fuel flow)] / 2 = Average Fuel Flow
11.12.2.2. Present fuel - Overhead fuel = Usable Fuel
11.12.2.3. Usable fuel / Average fuel burn rate = Fuel ETE
11.12.2.4. Fuel ETE - ETE to destination = Extra Time
11.12.3. AF IMT 4125, Range Control Chart may be used for in-flight fuel management.
11.12.3.1. Manual Construction. (Figure 11.4)
11.12.3.1.1. ―POINT NUMBER‖ represents the approximate level-off point (initial
cruise altitude), 25, 50, 75, and 100 percent of the flight plan distance as indicated on
AF Form 4116 or CFP.
11.12.3.1.2. To compute Column A, ―ENROUTE FUEL‖:
11.12.3.1.2.1. Record in Block 1 (L/O) the AF Form 4116 Block 7. Takeoff Fuel.
11.12.3.1.2.2. Divide the AF Form 4116 Block 1. Enroute Fuel by 4 and record
that number in each -25% Enroute block.
11.12.3.1.2.2.1. Optionally, a more accurate method is to compute the fuel at
each point and subtract them to obtain the enroute fuel burn between each
point. Put this number in the corresponding -25% Enroute block. This
method takes into account the initial higher burn rates.
11.12.3.1.2.3. Subtract this number going down the chart to obtain the enroute
fuel at each point. (e.g. 1. L/O - 25% Enroute Block = 2 (25%) enroute fuel, etc.)
11.12.3.1.2.4. The destination block will be takeoff fuel minus the full enroute
fuel.
11.12.3.1.3. To compute Column B, ―MINIMUM FUEL‖: