Jerry wrote:
"Not susceptible to fuel density changes (like a capacitance device)"
"Capacitance gauges may appear more accurate because they have better than
1/8th resolution but because of the variations in fuel make up they are
often less accurate. The difference being with our gauge if it indicates 20
litres you have at least 20 litres. Whereas with a capacitance gauge if it
says you have 22.5 litres may have 22.5 litres then again you may not."
This is not so, it's the opposite that happens, capacitance gauges are used on
large aircraft because they do show actual contents, e.g. the mass of the
remaining
fuel which is what you need to know.
When the temperature of the fuel changes, the volume changes, but the calorific
burn value is still the same. This value may change with the quality of the
fuel,
but with a volumetric gauge you'll be further away from the truth I think.
I can however imagine that the capacity type may be difficult to get to work
well
on a small aircraft and as the variation in exactitude of the switch
arrangementdue
to temperature change is so small I'd go for the simple type myself.
Your wannabee fellow builder,
Alex
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