Ul gas tank questions

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ryanjames170

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Apr 29, 2012
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So I know it's limited to 5 us gallons but my question is,

Is 5 gallons total cubic volume of the tank.

Or is it 5 gallons of fuel plus expansion room.

Or is it 5 gallons usable plus room fir expansion and a sump ie water trap or fuel at the bottom below the fuel pick up.
 

mcrae0104

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However much 1,155 in3 of gas expands at whatever altitude you can reach in a Pt. 103 craft, the FAA will not be able to measure your tank capacity until you land.
 

cdlwingnut

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I would say as long as there is a sticker or other saying max capacity 5 gallons and when you put 5 gallons of gas in it it looks pretty much full you will be ok
 

pictsidhe

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Unless they have some reason to want to bust you. You are probably OK with a '5 gallon' plastuic gas can. Those do take over 5 gallons, though. a pair of 2 gallon ones would be nearer the mark.
 

TFF

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The standard has been fly on 5 and have 5 as baggage if you need to fly that far without access to fuel. If you need to be in the air that long in a 103 UL is the wrong tool In the box, and usage judgment is out of whack of the utility of a real UL.
 

pictsidhe

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The standard has been fly on 5 and have 5 as baggage if you need to fly that far without access to fuel. If you need to be in the air that long in a 103 UL is the wrong tool In the box, and usage judgment is out of whack of the utility of a real UL.
Extra Baggage fuel isn't allowed under 103 unless the total fuel carried is under 5 gallons. Though I'm sure some people do it. The rule is 5 gallons total fuel capacity, usable and unusable. If you don't want to leave some expansion space in your 4.9999999999 gallon tank by partially filling it, you can have a seperate expansion tank. Just as long as you can't somehow fill it while filling the tank. A vent hose and locating the expansion tank above the fuel tank sorts that out. Or, build your tank so that when full to the top of the filler, there's some expansion space above it.
5 gallons should get you quite far.
 
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