Fighter and other tactical aircraft pilots are getting a new device that will make urinating and flying a lot easier a task. The Aircrew Mission.
Some have a “relief tube” that they pee into (sometimes attached to a venturi on the outside of the aircraft that causes a bit of suction), others provide the pilot.
Fighter pilots do not have any problem taking food and drinks on flights. The biggest As its been stated, its a plastic bag with powder in it that reacts to urine.