From the moment passengers arrive at the airport, flight numbers guide them through the correct departure lounge and to the flight they have booked.
They are also vital for taxi companies to monitor when their customer lands.
However, there is more to the numbers than just a jumble of letters and digits.
In fact, there is a lot of information hidden in your flight number, from the direction your plane is flying to how important that route is to the airline you are flying with.
Each flight number begins with two or three letters, most of which are familiar with which airline you are flying with.
These codes are assigned by the International Air Transport Association (IATA), the trade association of international airlines. And of course, no two airlines can have the same code.
Many seem like a no-brainer, for example AA is American Airlines, BA is British Airways and NZ is Air New Zealand.
However, others are less obvious – like WN, the code for Southwest Airlines, and AY, used by Finnair.
When Southwest Airlines looked up its code, SW was already taken – and still used today – by Air Namibia. This is because Air Namibia used to be called South West Air Transport.
Similarly, Easyjet used to use code U2 as EZ was already in use. But the low-cost airline now uses the three-letter code EZY instead.
After the digits comes a series of numbers that contain much more information about the flight.
Each individual flight number must be between one and four digits long, although there are certain numbers that will never appear.
The number 13 is never used due to superstition, while the number of the beast 666 is also avoided at all costs.
Certain countries have different numbers that they will not use.
For example, in China the number four is considered unlucky because the word for four sounds very much like the word for death and is therefore used sparingly, if at all. For this reason, many hotels and buildings will also do without the fourth floor.
However, the number eight in China is considered very lucky, so Flight 888 would be a great plane to fly.
Meanwhile, American Airlines Flight AA1776 from Boston to Philadelphia pays tribute to the signing of the Declaration of Independence that took place in Philadelphia in 1776.
The numbers also provide information about the possible destination of the flight.
For example, northbound and eastbound flights are often even numbered, while southbound and westbound flights are odd numbered.
The return trip is often one number higher than the outward flight.
Travel + Leisure A great example of this was provided by JetBlue’s flight from New York JFK to LA Airport – the outward leg is JBU523 while the return leg is JBU524.
However, some airlines will do things differently, like Qantas. using odd numbers for outbound international flights and even numbers for inbound international flights.
Certain flights are often considered more important than others, which airlines usually assign lower numbers to.
The rule is: the lower the number, the more prestigious the route – like Qantas Sydney-London connection, QF1.
“Airlines often give their more prestigious long-haul flights lower numbers,” pilot Patrick Smith previously told news.com.au.
“If there’s a flight 001 in an airline’s schedule, it’s the London-Sydney or Paris-New York stuff.”
Meanwhile, these are the meanings of the codes on your boarding passes and which letters you never want to see.
And you can use your flight number to let your friends and family know where you are.
https://www.thesun.co.uk/travel/20504515/flight-numbers-mean-plane-airport/ What the flight numbers on your boarding pass mean & why some will never be used