Hey, I figured out the temp/density thing. But to be sure, the hell with volume. I want a mass flomomometer thing, because I just spent x/10ths of an hour reading about it. One which rotates, even if only a teensy bit.
A bit more on metric vs imperial.
In the context of operating an aeroplane it makes no difference provided there is consistency. I don’t mean consistency of either imperial or metric, I mean that as long as fuel volume is always a particular unit of measurement, and weight for a particular aircraft type is always a particular unit, it really doesn’t matter.
I live in a metric country but for several years I flew an aircraft that received fuel in liters and burned fuel in gallons, then I started on a different type of aircraft that burned fuel in pounds, and my current type burns fuel in kilograms. None of this matters because they are all just numbers. The Aerocommander burned 24 gallons per hour, the Dash 8 burned about 1200 pounds/hour and the BAe146 is around 2300 kg/hour. They could each be burning “snobgoblins”, “stoatwarblers”, and “snarfleglasters” for all I care, as long as the fuel gauges are calibrated in snobgoblins, stoatwarblers, and snarfleglasters respectively and our operating manuals refer to the appropriate unit for each aircraft type. Problems only arise if you have some Aerocommanders burning snobgoblins and others burning stoatwarblers, or, as in the case I mentioned earlier, nine Dash 8s burning pounds and one burning kilograms, that is when you are being setup for a Gimli style mistake.
We don’t do the kind of calculations that benefit from the metric system. Conversions must be made whether using imperial or metric units and so it just boils down to using a particular conversion factor to get from one unit to another.
If fuel had the same density as water it would be another matter, because for our purposes you could say that a liter of fuel equals a kilogram of fuel and so using liters and kilograms would have a definite benefit.