Why do we use, in military aircraft, the words "Joker" and "Bingo" to indicate the fuel status of the aircraft? What is the history of these two terms?
"Bingo" originated with aircraft carrier operations. "Bingo" actually means to divert.
The official US Navy definition of "BINGO" is: "An order to proceed and land at the field specified, utilizing a bingo profile. Aircraft is considered to be in an emergency/fuel critical situation. Bearing, distance, and destination shall be provided."
If the aircraft carrier was operating in an area that had a land based alternate airport, it would be called "Bingo Ops". "Bingo Fuel" was the amount of fuel remaining to safely reach the "Bingo Field". The "Bingo Field" was the closest land based airfield which could be used as a backup in case the aircraft was unable to land on the aircraft carrier for any reason. Examples could be a fouled deck due to a disabled aircraft, or unusable arresting gear system.
Other military, and even civilian operators, have since adopted "Bingo Fuel" to mean minimum fuel to safely reach an airport.
My own research shows that there is no definite answer to the origin of Bingo.
"Joker Fuel" is a predetermined amount of fuel in excess of Bingo Fuel.
bingo fuel was fuel gauge malfunction estimated time of flight to rely on but I would rather play it safe
joker fuel was "wild card" your guess is as good as mine however I bet you my guess is better than yours, initiating to command and everyone else listening in that, you have doubts about ground support and that you think the enemy could be amongst you.