Why do flights divert and what to do when it happens

Going for a holiday can be an exciting experience, but what happens when your flight gets diverted all of a sudden when you are in mid-air? Although not a common occurrence, it can happen for various reasons such as inclement weather, aircraft problems, and medical emergencies.

Despite the inconveniences resulting from an unexpected diversion, it is important to remember that the primary reason for a diversion is to ensure the safety and well-being of passengers and crew. It is also useful to know that the decision to divert is the pilot’s prerogative, taking into consideration all the factors facing them at that moment, and the potential impact on the passengers onboard and the airline. There is also a set of SOPs set by the airline that the pilot and crew have to follow when a diversion is needed. From where to divert to, how to handle the incident, to safety procedures on board, these have been carefully mapped out by the airline.

Let's take a look at the different reasons for flight diversions, what should you do in such an instance and what measures you can take to mitigate the impact of a diversion.

Reasons for flight diversions

1. Inclement weather or natural calamities

One of the most common reasons for a flight diversion is bad weather and natural calamities. Singapore faces monsoon weather at certain times during the year. During rainy seasons, inclement weather is a common cause for diversions of flights heading to Singapore as visibility may be impacted during such situations. Pilots will usually choose to hold the plane in the air while waiting for rain clouds to pass. However, the pilot will have to divert when the plane faces the risk of running out of fuel and can no longer hold in the air.

Natural calamities such as a volcanic eruption leading to an overhanging ash cloud is another cause of diversions.

Flights diverted from Singapore’s airport typically get diverted to airports in the region including Batam’s Hang Nadim International Airport or Kuala Lumpur International Airport in Malaysia.

2. Aircraft problems

Another cause for a flight diversion is issues with the aircraft. These can range from minor technical glitches to more significant problems that require immediate attention, such as a fire onboard. If the pilot detects an issue, he will assess the situation and decide whether it's safe to continue the flight or divert to another airport.

3. Medical emergencies

Medical emergencies can occur during a flight. If a passenger falls ill or requires immediate medical attention, the pilot may choose to divert the flight to the nearest airport with medical facilities (subject to air services agreements with the destination country).

In the meantime, the crew will usually request for the assistance of medical personnel onboard so that the passenger receives medical attention as quickly as possible.

4. Closure of runway at destination airport

Another reason for a flight diversion is the closure of runway at the destination airport. A runway might be closed unexpectedly for various reasons, from an incursion that bars entry into the runway temporarily, to aircraft accidents which will cripple the runway for a few hours. In such instances, the pilots will usually choose to divert to the next nearest possible airport.

What you should take note of when your flight is diverted

1. Stay calm

Passengers should remain calm during a flight diversion. While it can be a stressful and disruptive experience, it's essential to remember that the pilot is doing everything possible to ensure the safety and well-being of all passengers and crew.

If it’s a medical emergency, airlines do seek the patience and empathy of passengers for the affected passenger.

2. Follow instructions and be patient

Passengers should listen carefully to instructions from the flight crew. The pilot will provide information about the reason for the diversion, what passengers should expect, and what they need to do. As diversions require substantial coordination between the flight crew and various parties such as air traffic controllers and ground handling agents, the airline will strive to provide the information in a timely manner. Following instructions will help make the process smoother and less stressful for everyone involved.

Be assured that airlines do want to do their best to get their passengers to their destinations as quickly as possible. Not only is it their responsibility towards their passengers, business-wise, delays come at a cost to the airline as well.

3. Stay connected

If the diversion results in a delay or rerouting, airlines will often provide updates via their own platforms.

Families and friends waiting to receive their loved ones should also check the airline's website or social media pages for updates, Changi Airport’s website or the Changi App for the latest updates.

Some considerations of the airlines that you might not know of

1. Where planes are diverted to

Where planes are diverted to depends largely on two key factors – air services agreements with other airports and the size of the aircraft in question. Other factors include the weather at the airport to be diverted to, length of the runway, and amount of fuel remaining in the aircraft.

For the first case, air services agreements need to already be in place between the origin and destination airports for the latter to receive the arriving aircraft.

For the second factor on the size of the aircraft, while smaller aircraft face less of an issue, larger aircraft can only be handled by airports with runways of a certain length. For instance, an A350 aircraft will need a minimum runway length of 1,600 metres for landing and 2,000 metres for taking off, while an A380 requires 2,150 metres for landing and 3,000 metres for taking off, fully loaded.  

Where to divert to would also have been mapped out by the airline prior to each flight takeoff under the airline’s emergency plans.

2. Flight time limitations for crew

Sometimes even though the issue which caused the diversion may have been resolved, and the aircraft is deemed worthy for departure, it may not be possible for the flight to continue to its final destination. This could be due to the crew’s flight time having reached its limit.

A crew’s flight time limit is typically eight to 10 hours. It starts when the crew clocks in for the flight, till when all duties pertaining to the flight are completed. This means that even if the aircraft is ready for takeoff but if the crew’s flight time limit has been reached, the crew need to be taken off-duty to rest and the airline has to arrange for another set of crew to replace the original set.  

A flight time limit is imposed as studies have shown that if a person works longer than eight or nine hours, the risk of an accident increases exponentially for each additional hour worked. The flight time limit for crew is determined by the aviation governing body in each country. 

3. Can passengers disembark when waiting for the issue to be resolved?

One would naturally ask – if the airline knows that it may take hours for the diversion issue to be resolved, why not allow passengers to disembark and enjoy some space within the airport? That would make the waiting more bearable.

However, whether passengers can disembark at the airport depends on a few factors including approvals by the relevant authorities and whether the airport has the ability to process and accommodate passengers from the diverted aircraft.

It should also be noted that even if disembarkation is allowed, most of the time, passengers would not be able to roam freely at the airport. They would likely be held at a particular location within the airport as they have not been security-cleared, and hence are not allowed to mix with departing passengers, who would have had their security checks done.

4. What travel insurance might cover in the event of a diversion

Since flight diversions are unexpected occurrences, passengers may wish to consider protecting themselves with travel insurance, which provides a small sum compensation for flight diversions and missed connections. Do note that travel insurance plans have specific terms and conditions for claims, so do check the plan’s benefits carefully before you purchase.  

According to the General Insurance Association of Singapore, travellers can only claim under one of these two benefits for the same event. This means that should their flights be diverted and they miss their subsequent travel connections, they can only claim for one of these benefits - Trip Diversion, Travel Delay or Missed Connections. Generally, insurers will pay the benefit that gives the highest benefit amount, subject to the policy’s terms and conditions.

To make claims for travel inconveniences covered under travel insurance policies, travellers should provide official documentation or written proof from the airline indicating the number of hours of delay, and the reason for the diversion and/or delay.

 

While flight diversions can be an inconvenience for passengers, it’s not something anyone wishes for, or can anticipate. A diversion is usually a last-resort measure and the airline's priority is to ensure the safety and well-being of all passengers and crew.

On the whole, flight diversions affect only a very small proportion of all flights, so don’t let this deter you from exploring the world more!

 

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