What causes a flight delay?

There is a good chance that if you try to inquire about the reason of your flight delay or cancellation, you’ll hear the mystical expression “operational reasons”. It appears to serve as an all encompassing waiver of responsibility, and had it been true, you could call up your boss and say you can’t come into work tomorrow because of “operational reasons”.

The fact of the matter is that delays and schedule disruptions are part of the air travel game mainly because of the multitude of factors that come into play when operating a commercial airplane. But for the sake of curiosity, let’s take a look at some of the most common factors that cause a flight to be delayed or cancelled.

Air Traffic

Since the 1980’s, air passenger traffic has grown from half a billion to well over three billion passengers a year. That is a lot of airplanes and a lot of traffic. Even more so around some of the world’s busiest cities, like New York, London and Paris. Longer flights also come with more restrictions and regulations, with airlines often changing their routes last minute due to weather and jet streams. The latter gets even more complicated because of airlines’ effort to be cost effective and optimize their fuel efficiency.
Infrastructure is another issue: certain areas of the world do not get the same radar coverage as Europe or the United States, for example. This forces air traffic regulators to require larger periods of time between take offs and landings to ensure safety, which easily turns into a chain reaction if one or more flights get delayed.


You may wonder, how is that in this Emirates commercial Jennifer Aniston is having a drink at the bar of an A380 while in flight, and yet your long-booked vacation starts off with an overnight lay off because of an engine failure. Well, as much as aircraft technology has improved, technical defects continue to occur. Every technical issue needs to be documented and addressed according to protocol, as “safety comes first”. That being said however, airlines are not exempt from paying compensation, when there is a technical issue with your aircraft, even if they try to convince you otherwise by emphasizing the importance of safety.

Flight crew rest requirements

Regulations are set in place to ensure that flight crew - meaning pilots and flight attendants - are well rested before your flight. Sometimes crew may max out their hours because of scheduling difficulties or a rotational delay (delayed, which is caused by a previous flight) and your plane will be grounded. Again, this does not exempt the airline from compensating you, as it is their responsibility to ensure that all crew rest requirements are met prior to your flight.


Passengers can easily delay a flight as well. When you hear Mr. Smith being paged on the intercom three times in a row, it isn’t because the airline is being nice to him and giving him a second chance to make his flight. When passengers have checked in their baggage but failed to turn up at the gate at the required time, the airline needs to find and unload their luggage - that is a safety requirement in nearly every country in the world.
Passenger behavior and health concerns are other reasons that can easily cause a flight delay. A Ryanair flight from London to Bratislava got recently delayed due to a group of gentlemen going to a bachelor party getting into a brawl with each other after having consumed a considerable amount of alcohol. Authorities try to limit this type of behavior by implementing some hefty fines - in this case, the party group faced a fine of £20,000 each.


There’s a reason why insurance companies call this an “act of God” - you can’t do much about it. Different airports have different standards when it comes to delays caused by poor weather conditions, usually determined by national regulatory bodies. Weather delays are much more frequent than you may think and they most certainly do not only happen in the winter.

Your flight will get delayed sooner or later. Do you know what to do when it happens?