How much fuel

[wilderobb]

How much fuel would a pilot put in his tanks, (Twin Engine Prop. for example, if he were to fly only half the distance he could have if he had full tanks. Is there a common percentage or standard procedure? I know people critisize me for driving around town with only a quarter tank of gas most of the time. The way I figure, the less fuel needed in my tank = better milage. ie. A lighter load. What say Ye?

[Jared]

depends on a lot of things..

I can't really answer your question fully, but I know that it is not a good idea to let an aircraft sit without full tanks for too long, since condensation tends to occur in the tanks thus causing problems with the engine in flight in you are unfortunate... ;-)

[beefhole]

Depends on the aircraft.  Us cessna pilots (I guess 8.5 hours actually makes me kinda a wannabe  :'( ) use the Jeppessen flight computer and our aircraft POH. For the rest of the simmers, and thanks to Nexus, I now have a very accurate model for fuel calculations-the only catch is you have to be familiar with your aircrafts FF at cruise.

Take FF at cruise and multiply it by flight time.

(This model is for a 737, I only do fuel planning for jets)

7400 lbs*1.6(1 hour 36 mins-it must be in the format 1.6!)

+7000 lbs(this is variable) for taxi, takeoff and reserve.

[birdie]

The Canadian Regulations for a twin-engine prop is enough fuel for start-up, taxi, climb, trip, and a 30min reserve for a VFR flight.  For an IFR flight you need the enough for start-up, taxi, climb, trip, conduct an approach, a missed approach, fly to alternate airport, and 45 min reserve(20min reserve for jets).  I fly a Twin Otter on floats in the summer and we just take the minimum fuel required so we can load as much stuff on the plane as possible.  I am sure that it isn't much different in other countries.  Cheers!

[Skittles]

I created a little Flight Fuel Planner for this very thing.

http://www.anadrac.com/Downloads/FFP.exe

It's a little corney, but effective.

[Brown]

I would say to have about  30 min fuel reserve because of holding patterns and delays. Also I belive it is a FAA law that say's that you have to have 30 min extra . Also about leaving fuel in your tanks a flight crashed because of that . So use discresion when considering how much gas you need .

[logjam]

I think Birdie quit reading CARS long before the last amendment in 1999. Section 725.25 Fuel Requirements show the en-route reserve to be 5%, that's becuz some little planes don't even have 45 mins fuel. There are some areas that allow a reduced amount of reserve and then again if you are flying for Air Transat in a biggie, you'll have to tow a reserve fuel tank and fly within 100 miles of land since the episode of the Grand glide to the Azores

[Brown]

When I fly I try to make sure I have at least 40 min of fuel to last me . The reason I do this is that a pilots main concern should always be on his aircraft and the saftey of the plane .

[beaky]

If you want to go half the "book" range, including reserve for delays/getting lost/wx diversions and fuel for taxi/takeoff/climbout, you'd put in half what the tanks will hold. I suppose you could get really into it and factor in hourly consumption based on the lighter fuel load, but I bet you wouldn't see much difference (for light singles, anyway).  I've never done a serious study, but most light aircraft don't get much better mileage with only 100 or so less pounds aboard (typical full-tanks weight is 40 gallons- times 6lbs/ gal.). The same is probably true of your car, which probably holds 20 gals. max. And the safety factor of full tanks is worth more than the money saved on gas. Also, to save money, a lot of aircraft owners don't lean the mixture much- it can cause higher temps, which could shorten the life of the engine  (overhauls are not cheap!). I'm a renter who gets "wet time" (fuel included), so always top it off on cross-countries, just to be sure. It's easier to remember how much you started with if it's always the same amount (and you have to KNOW what you've got- the gauges are useless)!  The only time I ever took off without full tanks was in a C-150 that had about 2.0 hrs. worth - I was just practicing pattern work, and there was  fuel at the field. The only reason it wasn't topped off by the previous renter was because they returned after the pump was shut down the previous day. Fuel is of no use to you in flight if it's on the ground, and money won't help you up there, either.

[congo]

I use the Flight Planner and it gives me a fuel burn estimate. I more than double it and I still run out on final, almost guaranteed...........  :P

[beefhole]

Current FARs state that you must have 30 mins reserve daytime and 45 mins reserve nightime.

[birdie]

I didn't know that Logjam!  I did my commercial licence in 1998.  I guess I will have some studying to do for my ATPL coming up late next year LOL.  Cheers!