The airline industry is a mysterious world filled with abbreviations, protocols and secret code that once unlocked, reveal a glimpse into the thousand decisions and actions going on behind the scenes of your flight. Intrigued?

Read on as we reveal the secret language of cabin crew with the help from our industry insider Anna* who works for Qatar Airways...

(*We've changed her name so she can really spill the beans.) 

Pax means passengers, just in case you overhear a flight attendant say: “We have 30 pax on board”. If you also hear the word 'payload' used in relation to pax, it means the combined weight of passengers as well as cargo. Anna says: "Also, when we are talking about a passenger, we use their seat number to refer to them, such as 6 GOLF or 32 BRAVO."

Less revolting than you think (but certainly not complimentary to passengers) gate lice refers to the over-eager people who crowd around the gate before boarding has been announced. They are laser-focused because they usually have carry-on bags and want to ensure they get an overhead bin just above their seat.

The briefing before a flight is conducted either in a special room in the terminal or in a quiet corner away from passengers. Sometimes it's on the aircraft before passengers get on the plane. "At the briefing we introduce ourselves to each other, because it’s usually the first time we meet," says Anna. "We discuss flying time and flight level, country and airport requirements for passenger and crew service. Supervisors ask safety and first aid questions from the cabin crew, to ensure their knowledge is up-to-date. We also discuss the number of children on board, frequent flyers, passengers who require assistance and any kids travelling alone."

During the pre-flight briefing, the following passengers are always flagged up: INAD – inadmissible passengers, who usually have problems with visas or passports, DEPU – deportee unaccompanied, and DEPA – deportee, person in lawful custody. "They must be viewed as potentially disruptive, have to be monitored during the flight and are usually seated in the last row of the economy section," explains Anna.

When you hear someone referred to as PRM, it stands for 'passenger with reduced mobility'. Crew need to be aware of who needs assistance during the flight, those who require a wheelchair in-flight to use the toilet or when disembarking, or any passengers with injuries such as a broken arm or leg. They cannot be assigned to an exit row seat however, even though it offers more space. 

ABP stands for 'able bodied passengers'. "These are passengers that the crew would select to assist in an emergency," says Anna. "If you want to sit by the emergency exits we have a list of criteria you must meet. The minimum age is 18, you must appear to be reasonably fit, strong and able to assist the rapid evacuation of the aircraft in an emergency. They tend to be crew members travelling as passengers, policemen, fire fighters, military personnel, or any person who is physically strong and able to follow instructions."

Runners are people sprinting to a connecting flight because the first flight was late. You might hear the crew or ground staff say: "We have runners along the way.” Depending on the strictness of departure times (it costs the airline thousands of pounds to delay) the flight may still leave without them.

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This refers to occasional passengers who turn up late and don’t have an assigned seat. They're called ‘spinners’ because by that point they’re flustered and flapping around, and looking for a seat and a space in an overhead bin.

This procedure may sound like a rushed job but it actually takes about 30 minutes. Usually it means the ground crew need to finish things off in their log book, or maybe there is a change to the flight plan. "Usually it’s something to do with the weight-and-balance record, a revision to the flight plan, or waiting for engineers to deal with a write-up and get the aircraft logbook in order," explains Anna.

You'll often hear the words 'cross-check' announced over the intercom. "Before departure, all the aircraft's exits are put into emergency mode," says Anna. "This means that if the door needed to be open, the escape slide or slide raft would automatically deploy. The ‘cross-check’ part is where we physically check if the opposite door has also been armed. They must be armed for take-off and disarmed before opening after landing."

Ever been stuck on a plane for what seems like ages while another plane takes off? You might be in what’s known as the sin bin – an area the plane has to wait in to make room for another aircraft.

SOP stands for the 'standard operating procedures' the cabin crew perform on board. "We have thousands of SOPs," says Anna. "They could include placing a coaster under certain glasses in business class, napkins going under mugs, offering biscuits with a hot drink, keeping the exits clear from bags, blankets or any loose items for takeoff and landing, opening the window shades for takeoff or landing and giving toys to children. Even removing the hats for female cabin crew after the last door is closed."

No, this is not code for Curacao or some other exotic liqueur – blue juice refers to the liquid that is used to flush the contents of the aeroplane toilet. If you hear "there’s no blue juice in the toilet", it's best to steer clear until they refill it.

The bulkhead refers to the partition – either a curtain or a wall – that separates the seating areas, often between two classes of cabin, or the lavatory and the galley. Bulkhead seats tend to have a bit more legroom than most.

Otherwise known to us civilians as ‘fasten your seatbelt’, crotch watch is the check flight attendants undertake to make sure you’re safe and secure before takeoff and landing. 

Every crew member has an assigned station on the plane. When an announcement goes out saying ‘all-call’, that’s a request for every person to go back to their station.

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No, not the Football Association, it stands for flight attendants. When heard in the context of, for instance, ‘F-As to all-call’ that means flight attendants must report to their assigned station.

You'll sometimes hear 'first officer' mentioned in the captain's announcement before takeoff, and what they are referring to is the co-pilot of the plane. They sit next to the captain in the cockpit on the right, and are fully trained in takeoff, flying and landing the plane, and sometimes alternate with the captain.

If you hear someone talk about the ‘heavy pilot’ they aren’t being rude about their colleague's waistline: it’s used to refer to the extra piloting crew some long haul routes require to allow pilots to take their required breaks.

On long haul flights, cabin staff will sleep in a crew bunk. "There are two rest periods between the two main meal services," says Anna. "The rest is around three to five hours long, where half of the crew take the first rest period, and the other half goes for the second. The crew bunks or crew rest compartment are located in the rear of aircraft for the cabin crew (upstairs on Boeing 777 and Airbus A350, and under the passenger level on an Airbus A380) while the flight deck crew rest is in the front of the aircraft." 

A plonkey kit refers to the kit that crew members bring on board. It has some personal items such as toothbrushes and hand creams, but also items potentially needed for the flight such as a sewing kit, ice tongs and oven mitts.

Oddly ‘equipment’ is used to describe the aeroplane. So if you hear there has been an ‘equipment change’ that means the plane has been swapped. Anna says: "It can also refer to emergency equipment such as fire extinguishers, smoke hoods and portable oxygen."

Like 'an area of weather' which indicates a thunderstorm or heavy rain, air pockets are often announced to give you a heads up that there may be turbulence ahead. The aeroplane might be entering a spot of low pressure meaning it might feel like it is dropping slightly, but it's not something to worry about. 

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Nothing too sinister – a deadhead refers to a crew member who is travelling as part of an on duty assignment. For instance, someone may have to travel from London to Rome in order to operate or service a flight from Rome to a different destination.

If you hear crew members referring to a colleague being on a 'ferry flight', that's when an empty aircraft is being flown from one place to another without goods or commercial passengers on board. Anna says they are rare but that "it’s a chance to have some fun on the flight for the cabin crew." She adds: "It usually happens when there is a major technical issue with the aircraft and the cabin crew and pilots need to bring back the aircraft. If it takes a few days to fix the plane however, the airline deadheads the crew back on a normal scheduled passenger flight, and only asks the pilots to fly the aircraft back."

Anna describes an outstation as a destination where the crew stays overnight. It isn't a major hub for the airline, but a smaller airport.

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UM stands for 'unaccompanied minor' meaning children between five and 11 years of age who are travelling alone. "We have to look after these kids, because they are travelling without their parents or family," explains Anna. "We check on them very often, make sure they eat and drink and that nobody bothers them."

You might hear the cabin crew saying: "Do the flight deck need anything?" and they are simply referring to the cockpit, and maybe the captain or the first officer have requested something. 

When your pilot announces ‘we’re in the hold’ they aren’t revealing that they're locked in with your luggage, but referring to the holding pattern that planes are kept in, while awaiting instructions from air traffic control on when to land. 

EFC time stands for 'expected further clearance' time, which is the time when crew know they will be released from a holding pattern. It’s also when the plane can be expected to takeoff. Wheels up, by contrast, is the time the plane needs to be airborne.

This announcement on the personal address (PA) system is made by the pilots around five to six minutes prior to touchdown and isn't just a signal the journey is drawing to a close. "At this time cabin crew mentally prepare for unexpected emergency situations that may occur during landing, taking into account both inside and outside conditions," reveals Anna. "We focus our attention on safety and that enables us to respond quickly and correctly in the event of the emergency." 

The CSD is the cabin service director who is in charge of the cabin crew on larger aircraft. The CSD oversees the cabin crew by making sure the passengers are safe and comfortable. "They write reports and ensure all SOP (standard operating procedures) and SEP (safety and emergency procedures) are followed," says Anna. They also solve issues with passengers and even cabin crew conflicts."

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