What Might Cause A Plane To Divert?

While airlines always do their best to get you from point A to point B, there are times when circumstances may cause an aircraft to divert to a different airport. With that in mind, we thought we would take a look at what might cause a plane to divert to an unexpected destination.

Planes do not get diverted all that often. Photo: Getty Images.

If the flight you are on gets diverted to another airport, one of two things will happen:

  1. Your flight will resume when the conditions are more favorable.
  2. Your flight will terminate at the diverted airport, and the airline will bring in another aircraft or bus you to your original destination.

If you were booked on a connecting flight, the chances are you will miss it unless you had an extremely long layover. If you know that there is no way you will make the flight, work with the airline to rebook for a later time.

But what causes planes to divert? Let’s take a look.


While every attempt is made to forecast the weather at the arrival airport, the situation can change hour by hour. On short regional or commuter flights, it is easy to predict what the weather will be like when landing. Long-haul flights, however, are something else entirely, with pilots relying on forecasts regarding conditions.

American Airlines snow
Flights in the USA often get diverted due to bad weather. Photo: Getty Images

While high winds are not a problem, they become an issue when they blow sideways across a runway (crosswinds) and exceed 35 knots (40.2mph). A lot also depends on the aircraft type and airport where the plane is landing.

London City Airport (LCY) has a short, narrow runway that shuts down when crosswinds exceed 25 knots (28.7 mph). Heathrow, meanwhile, can stay open because its runways are longer and broader.

Snow is often to blame for diversions and canceled flights, especially so at airports not used to large amounts of snowfall as they don’t have the equipment to handle the removal. Fog, too, can play a role along with low cloud and poor visibility.


Modern aircraft are incredibly complicated machines and, like all things mechanical, sometimes need parts replaced. Safety is, of course, an airline’s first concern, and when a pilot is notified that something is wrong, their priority is to communicate with the ground and to make the right call in terms of whether to continue the flight or not.

The outcome depends on the type of emergency and the other factors to be considered, such as how much fuel is on board. If the situation is not dire and fuel not overloaded, it may make sense to return to where they took off from. 

If the aircraft is further away, it may opt to land at an airport where it has a hub. By doing this, passengers will quickly get to their intended destination, and the plane will have mechanics and spare parts at hand to fix the issue.

Medical emergency

Airline crews are trained in first aid, and are well placed to consider whether a medical emergency requires an urgent landing or not. In a serious situation, they may ask for a medical professional on the flight to come forward. At the very least, they can administer emergency medical assistance until the plane arrives at its destination or nearest airport.

Flight attendants are trained in first aid. Photo: American Airlines

Unruly passenger

If there is an unruly passenger on the plane, the Captain will decide if he or she poses a threat to the aircraft, passengers, and crew. If so, the Captain will look to land at the nearest available airport and have the police remove the troublemaker from the plane.

Other reasons why an aircraft might divert can be due to natural disasters such as a volcano erupting or the sudden outbreak of an armed conflict.

Plan ahead

You never know when a plane might get diverted, which is why it is always a good idea to plan ahead. If you are flying down to Florida to get on a cruise, why not arrive a day earlier and spend the night in a hotel. The same thing goes for a family celebration or anything that you don’t want to miss. Always pack medications and items you need in your carry-on as you never know how long it might take to get to your destination.

United luggage bins
Put medications and items you might need in your carry-on. Photo: United

Most airlines these days are well prepared to handle the occasional diversion and will do their best to get you to your original destination as soon as possible.

The most extended time that we know of where people were stranded following a diversion was when aircraft diverted to Gander, Canada, after 9/11. What is the longest time you were ever diverted, and how did the airline treat you? Please let us know all about it in the comments.