Figure 4-5 EFR Calculations for the First Low-Level

T-6A NAVIGATION

CHAPTER FOUR

Interpolating the data in Figure 4-3, we determine the descent figures of 10 NM, 13 pounds

rounded up to 15 pounds, and 2.5 minutes per 4000 feet altitude. Using the climb and descent

distances, the distance flown at cruise is computed as follows:

83 (Total distance from takeoff to PT A)

- 20 (10 + 10, Total distance in climb and descent)

63 (Distance flown at cruise)

Using the cruise fuel flow data, compute the fuel required to fly 63 NM at 240 KTAS. Dividing

63 NM by 4.0 NM per minute (240 KTAS) gives us 15 + 45 minutes. We interpolate fuel flows

for 240 knots at 10,000 feet and arrive at 450 pounds per hour, or 7.5 pounds per minute,

rounded to 8. Multiplying cruise time by fuel flow per minute = 15 x 8 = 126 (round up to the

next higher five pounds) or 130 pounds.

Subtracting, the cruise and descent fuels to Point A:

1005 ( Fuel remaining after climb)

-145 ( 15 + 130 or cruise plus descent fuel)

860 ( Estimated fuel remaining at Point A)

NOTE

In the previous example, we assumed winds were light and

variable. Remember, Ground Speed (not TAS) is used to compute

enroute times. Since winds affect your enroute times and thus your

EFR data, compute IFR enroute portions of the jet card using best-

known winds.

Remaining Low-Level Route EFRs

Given the EFR at point "A," the fuel flow, and ETEs between turnpoints, we can calculate the

EFRs for the first low-level. Round all computed leg fuels to the next highest five pounds.

A to B:

B to C:

C to D:

108

002

087

DIST

21.5

DIST

34.5

ETE

7+10

ETE

8+20

ETE

11+30

ALT

1500

ALT

1500

ALT

1500

EFR

790

EFR

AFR

MCF

BINGO:

Figure 4-5 EFR Calculations for the First Low-Level

FUEL PLANNING, JET LOGS, DD 175

4-5