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Quick one for the below. It says variable does not apply to alternate fuel which I understand; however, do we just ignore it in this case?
If we take 31.3 for alternate & fixed reserve. Should we not take 10% from 60 and then subtract 31.3? Or is this a case where the holding requires the use of the variable.
Fuel consumption in cruise ............ 28 US gal/hr
Fuel consumption for holding .......... 20 US gal/hr
Fixed reserve ......................... 15 US gal
Start-up and taxi allowance ........... 3 US gal
Variable reserve .................. 10% of flight fuel
The aircraft whose details are given above arrives in the circuit area and finds it cannot land immediately due to an runway obstruction.
The pilot recalculates his fuel and finds that he has 60 US gallons of fuel on board.
The nearest suitable alternate aerodrome is 35 min flying time away.
The maximum time for which this aircraft can hold before diverting to the alternate is closest to -
The wording of the question indicates that the aircraft has arrived at the destination and the pilot has recalculated the fuel on board. The trip is over so variable reserve is not a consideration. You simply take the fuel in the tanks when you arrive and take out the fixed reserve and the trip fuel to the alternate. That's 60 - 15 - 16 = 29 gals @ 20gph.