1. To have a drink prior to an airplane flight, usually to ease the tension of the flight or to make flying generally more enjoyable.

Got the covid-19 vaccine

Cunt.
The United States Air Force flightcap resembles the labia when viewed from the top or turned on end and has been called the "C" cap or cunt cap for years. Flightcap has become code for cunt cap and is a more subtle way of calling a person (usually female) a cunt.