PA28 Fuel management
Pompey till I die
Join Date: Nov 2006
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Welcome baclk
OK the 20 billion dollar question, why doesn't a PA-28 have the option to select both?
Join Date: Feb 2007
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I only post on PPrune whilst sat here revising for exams.. had a break for a while now started on Nav the last PPL exam for me other than the RT practical!!!. It makes a nice change from getting annoyed with trying to get the right answer from the devils wheel.
Good luck with the nav exam though.
Join Date: Jun 2003
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most GA gauges measure [i]volume[/] but fuel consumption is by weight
For a liquid, the two are practically the same. Avgas expands only 0.1% per degC. The biggest change one is likely to see (GA) is say +35C on the ground, down to -25C at FL200. That is a volume shrinkage of 6% - too little to see even on an accurate fuel gauge.
I believe you can see this on a flowmeter though. The standard Floscan 201 turbine flowmeter used with nearly all fuel totalisers in GA measures volume flow, I believe. So at the above FL200 example, the fuel mass flow will be underestimated (i.e. the error is on the dangerous side) by 6% but does this matter? You are still working in volume units; well I am - in USG.
If however your flowmeter was set to read lb or kg then you would have a real error because at low fuel temperature the flowmeter is under-reading because the fuel is heavier. This means the "FOB at destination" projection (from the standard flowmeter-GPS functionality) will be optimistic - if the flowmeter is set to read lb or kg.
Interesting!
Not that one should sail quite so close to the wind for this to matter...
Join Date: Jan 2007
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Some of the few things I've learn't about GA fuel planning when flying the likes of a PA28 on a longish cross country.
Plan your fuel based on time and don't get too smart calculating it to the litre using miles per gallon or gps functions. Don't assume you'll be flying in a direct line to your destination either!
Look at the weather and look at alternative airfields and consider how much fuel it'll take to get there from your destination. Don't just say, use your usual 45 mins reserve all the time (fine for your back yard local flying).
Keep the ball in the middle and change tank every half hour or so first checking for suitable fields and turning the electric pump on before messing about with the selector.
Never think "it's ok, I've got lots of fuel".... Especially when you're lost!
Don't smoke at the pumps.
Don't run with scissors.
Stay in school.
Do as your mummy said.
Plan your fuel based on time and don't get too smart calculating it to the litre using miles per gallon or gps functions. Don't assume you'll be flying in a direct line to your destination either!
Look at the weather and look at alternative airfields and consider how much fuel it'll take to get there from your destination. Don't just say, use your usual 45 mins reserve all the time (fine for your back yard local flying).
Keep the ball in the middle and change tank every half hour or so first checking for suitable fields and turning the electric pump on before messing about with the selector.
Never think "it's ok, I've got lots of fuel".... Especially when you're lost!
Don't smoke at the pumps.
Don't run with scissors.
Stay in school.
Do as your mummy said.
Join Date: Oct 2006
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The outfit I did PPL with had a PA28 checklist (which I use to this day) that instructs to start engine on the fullest tank, then change tanks for the power check, take-off and the first 30 minutes of flight.
Join Date: Jan 2006
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Back on my time on the PA28 I was taught to start on the RIGHT Tank then switch to the LEFT during taxi / checks.
Sole reason being in the event of an EFATO, the action of moving the fuel tank selector from LEFT to OFF is easier than RIGHT to OFF.
Always think worst case
Sole reason being in the event of an EFATO, the action of moving the fuel tank selector from LEFT to OFF is easier than RIGHT to OFF.
Always think worst case
Join Date: Feb 2002
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Sole reason being in the event of an EFATO, the action of moving the fuel tank selector from LEFT to OFF is easier than RIGHT to OFF.
dp
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Sole reason being in the event of an EFATO, the action of moving the fuel tank selector from LEFT to OFF is easier than RIGHT to OFF
It is only for the specific (and I suggest very rare) case of both wings undamaged but the engine fuel hoses damaged that turning off the fuel cock is relevant.
Join Date: Apr 2003
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I agree with the above comment re. taking off on the fullest tank. Let me elaborate; the outfit which checklist I refer to had our PA28s fully refuelled between each and every flight, so we always had full tanks on start-up anyway (AVGAS is cheaper Stateside 
).
Cheers
).Cheers
Join Date: Mar 2008
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PA 28 Fuel Mgt
I always do fuel planning for our Archer II at 40l/hr (giving 264 mins endrnc) and lean out in flight. Our motor has 50 hrs to run before replacement and on a 3 hr flight came back at 33.5l/hr burn rate. So better to plan at upper rate.
Another thing I was taught was to take off and land on the left tank so if you had to change tanks quickly it is easier in the PA 28 from the left hand tank, whether shutting off or changing to RH.
I agree with IO540 I'd rather walk away from a landing not having shut down properly than stuff up completely. Remeber every landing you walk away from is a good one.
Cheers
Another thing I was taught was to take off and land on the left tank so if you had to change tanks quickly it is easier in the PA 28 from the left hand tank, whether shutting off or changing to RH.
I agree with IO540 I'd rather walk away from a landing not having shut down properly than stuff up completely. Remeber every landing you walk away from is a good one.
Cheers
