British online friend: "Saw a flying banana tonight. I only noticed because of the purple light shining upwards"

Everyone: ???

"We have track measurement trains. They run around, checking the tracks for faults, the power cables, etc

They're bright yellow. So they're nicknamed the Flying Banana, as a joke on the Flying Scotsman

Night time they have this blue laser that scans the overhead wires. It creates this giant glow you can see when it moves"

@GreenSkyOverMe Japan has 'Doctor Yellow' for their maintenance train.

Flying Banana was used as a nickname for all the high speed train units in their original livery long before the NMT, and that was a reference to 1930s use for GWR railcars