On vacation I was on a plane, my dad didn’t know the answer either.
Answer
All aircraft have a “number plate”, a registration number, which is painted on the underside of the wings so that you can recognize the aircraft from the ground. Belgian aircraft have a registration number that starts with OO, such as “OO-HFE”.
Some airline companies also give their aircraft a “real” name, but this is not mandatory. KLM names its planes after princes or princesses, Lufthansa names them after German cities.

Answered by
Engineer Bart Dierickx
electronics imagers cryogenics metaphysical questions aerospace and the most impossible things

http://electroniade.org/
.