INTERMEDIATE FLIGHT PREPARATION WORKBOOK
1. A 6-minute gate is the GS in knots divided by 10 (since six minutes is
a tenth of an hour), and a 5-minute gate is the GS in miles per minute
multiplied by 10, then divided by 2.
2. Use aircraft clock (FT mode) for ETAs vice the elapsed time mode.
Estimated IAF Fuels
Estimated fuel at the IAF is given during the WL call and after each GS check. Several
techniques for fuel computation may be used. Four will be explained in the following
discussion. The following examples use the information below:
DISTANCE AND ETE1:
You mark-on-top of Pt. #1 at 40+00 with 4100 lbs of fuel. Enroute to Pt. #2 you complete a GS
check: You are traveling 420 KTS (7 NM/min). When you "freeze" the fuel quantity and fuel
flow, you have: time (44+00); fuel now (4040 lbs); fuel flow (1200 lbs/hr); distance to Pt. #2
(112 NM). Compute IAF fuel for wings level after Pt. #1 and IAF fuel after GS check.
112 NM ÷ 7 NM/min = 16 min to Pt. #2
16 min (to Pt. #2) + 90 min (Pt. #2 to IAF) = 106 min (to IAF)
Pounds Per Minute Method: Divide fuel flow by 60 to determine pounds per minute.
Multiply pounds per minute by minutes remaining to IAF.
1200 lbs/hour ÷ 60 min/hour = 20 lbs/min
Wings Level: 106 min x 20.0 lbs/min = 2120 lbs fuel burned to IAF
4040 lbs - 2120 lbs = 1920 lbs at IAF
Adjusted for preflight winds
T-1A FLIGHT PROFILES