Like all jobs, aviation has its own professional jargon.
"Deadheads", "B.O.B" and "cheerios" - most of the terms pass over passengers' heads.
A few years ago a rumour sprang up that there were certain code words that cabin crew would use to hit on passengers.
The "cheerio game" sprang up on a popular forum used by flight crew called cabincrew.com, entitled 'games to play mid-flight'.
"When you're standing there going 'buh-bye, thank you, take care' etc when you see someone you fancy, you say 'cheerio'," wrote Luton 330.
Of course if your flight crew says "cheerio", it does not mean they find you attractive. It means they are Mary Poppins.
However, it does show quite how curious what meanings might be missed in the highly codified and precise world of aviation. Like all technical fields, airline staff love acronyms.
The 2014 book Confessions of a Qantas Flight Attendant saw ex-flight crew Libby Harkness and Owen Beddall lift the lid on the secretive and scandalous code words used by crew.
The behind the curtains tell-all, started the rumour that bored crew have another favourite game: "Spot Bob".
Owen assures readers these three letters don't stand for anything scandalous. They are merely complimenting your behaviour.
"If you get called Bob, do not take offence, take pride. You've been awarded 'best on board'."
There are certain letters you don't want to hear while boarding a flight.
IATA, the International Air Transport Association, has an entire codex dedicated to SOSs.
There are about 100 different delay codes that ground crew, pilots and traffic control use to communicate with each other.
Different problems are denoted with a different combination of two letters or sometimes numbers. For example "DG" - "delay due to damage to aircraft during ground operations" - can be given as 47, for the fourth and seventh letter of the alphabet.
Delays due to unscheduled maintenance (TN), late luggage (PD) or missing crew (RS) all have codes.
Some of this is for records and technical, they perhaps are delivered in combinations of letters so as to not panic passengers.
Passengers, of course, come with their own category of delay codes. PE means there are problems with passengers' check-in details. PH is checked-in passengers not boarding the plane.
The two letters you never want to hear when checking into a flight are PO. This means the "plane is overbooked" and you're likely not getting on.
If you've memorised your phonetic alphabet here are the calls for a bingo game you don't want to take part in.
