[salawat]

Huh. Wait, aircraft use float based fuel gauges still? I thought everything had gone electro-resistive since you'll get the same measurement regardless of orientation of the tank if you place your sensors right.

I remember coming across that as a specific design challenge to overcome. Floats don't read the same when flying upside-down.

[Syonyk]

Most of the US General Aviation fleet is from the 1950s to 1980s. They still use floats.

Those who fly upside down on purpose tend to either not care about the fuel readings when upside down, or fly something modern enough. But I can't imagine an airshow performer is paying any attention to the fuel gauges. "I have a 15 minute routine, I have an hour of fuel onboard, and I'm surrounded by an airport, which is a good place for an emergency landing."