[AlanTheBeast100]

Better to keep records of fillups and miles between to work out the bias on the MPG meter.

On my car it's close to 1.3 MPG optimistic. This is pretty consistent over 59 full tanks of gas to date (2019.04 to present).

 

[AlanTheBeast100]

@Dammit I must confess, kilometres confuses the crap out of me. We use mm, cm, m, and once we get past a few 100m we revert to miles.

Same goes with drinks, we buy our milk and soft drinks in ml & litres, but buy our beer in pints and spirits in half or quarter gills - Imperial Gill = 142 millilitres.

It's a Brit Thing!

While I'm all for traditional beer units in the UK, it mystifies me that you still use miles but sell gasoline by the litre. I was picked up by a chauffeur at Heathrow to go to Yeovil one morning, and I noticed the sign giving the speed limit. He was driving at 100 mph, however and said "I know where all the speed cameras are". Only time I saw Stonehenge and that lasted a blink!

IAC on that program (Westland Helicopters at the time) everything was metric except parts of the nav system (knots, nautical miles; also used UTM and MGRS which are metric).

What irks me is this European unit of L/100km. Ack-basswards. It comes from the era when cars were far less efficient. Should have been km/L.

Of course Canada is stupid - so car mileage is expressed as L/100 km. It's not a hard conversion to do but it's a PITA.

Some useful constants:
1 foot = 0.3048 metres (exactly).
1 inch = 25.4 mm (exactly).
1 mile = 1.6 km (not exactly; 1.609 is close but still not "exact").
1 pound = 454 grams (not exactly) - 1 Kg = 2.2 Lbs (not exactly)

 

[AlanTheBeast100]

The reason we display or fuel in litres is due to EU regulations. It's the same reason why the 0-60mph times changed to 0-62mph as 62mph equates to 100kph.

It's also why our Speedo's display kph as well as mph. Yet mainland Europe registered vehicles don't have to display mph, for those that travel to the UK.

You missed out Cables and Shackles in your Nautical Measurements.

Lynx, Wildcat or Merlin, or all three?

I find the "62 mph" thing ridiculous. Why does it have to be a round number of km/hr converted to MPH (rhetorical - Eurocrats are a breed ...)

Speedos here (Canada) have been km/hr since the late 70's with MPH on an inner ring for driving in the US.
Conversely, US cars are MPH and some (many) had km/hr on the inner ring.

On my Accord, there is only km/hr, but I can cause a MPH indicator to appear in the middle of the console if needed via display options.

We don't have furlongs per fortnight in our nav systems either (though it's pretty trivial to do). I don't know what the ASW platforms use for depth. Feet, metres, fathoms ... depends on the nation. When we did nav for various Italian B-212's, the system had a program-plug (wiring harness) that would tell the nav system what displays, interfaces, units, etc. to use. Indeed, different services used different nautical miles. The standard has been 1852m for a long time, but some services had their charts with different values for a NM (Brits: 6080 feet for example up until 1939 IIRC).

EH-101 for Canada (Cormorant - not Merlin) and Italy (not sure what they call it).

 

[AlanTheBeast100]

Nice stuff. And on topic too!

 

[AlanTheBeast100]

Getting back to fuel economy: This is surprising. That's an average of about 36.5 MPG, assuming you took the same route both ways. That's about what I'd expect to get on the level. Of course speed would play a big part of the equation. You must have been light on the throttle.

You can't average an "uphill" and "downhill" amount to find the "flat" average. For a variety of reasons. If the amounts averaged to the same, it's a coincidence.

 

[AlanTheBeast100]

I live in the Mile High City (Denver). Here at my house I live at around 5,400' in elevation (1.65km for you @Hadleys Taxi).

(Quibble: metric altitudes are expressed in metres for things like mountain elevations, not km, thus, 1650m, not 1.65km).

 

[AlanTheBeast100]

Oh, but of course you can Miles traveled divided by fuel consumption.

Well, you can do the arithmetic, but it has nothing to do with the physics.