It’s no news they Heathrow Airport: UK’s best, and the world’s busiest airport, is known to experience a lot of delays and cancelled flights. Data from Flightera has it that 4,724 flights are cancelled at Heathrow Airport annually. While this is not new, many factors have been linked to this scenario, some of which include operational, structural, and external factors.
While some of these factors can be controlled, others can’t (but can be managed). Below, we have listed some known reasons why flights are interrupted at Heathrow Airport and measures put in place to mitigate these challenges.
Note: There are many more reasons for Heathrow airport's delayed flights, but the ones below are considered the most impactful.
Heathrow Airport is home to one of the world’s busiest two-runway international airports. During its peak hours, it handles flights every 45 seconds, recording around 480,000 movements per annum. With a situation like this, even the slightest interruption in airline traffic can cause either a delay or, worse still, a cancellation.
Another reason can be traced to the airport’s inability to handle unscheduled disruptions, which could lead to delays or outright cancellation.
Solution: To solve this challenge, the management of Heathrow has employed collaborative planning and a strategic punctuality method to solving these issues. In 2025, the management introduced a cross-airline initiative targeting the main reason for the delays. This recorded a significant improvement, with an immense reduction in compounding delays in airline schedules.
The management also applied AI and data-driven tools in 2026. These AI-powered cameras are designed to analyze aircraft positions in real time. This has greatly achieved a reduction in airline costs and improved punctuality in departures.
This is one of the most common reasons for delayed or cancelled flights at Heathrow Airport. Oftentimes, we hear the news of strong winds, fog, snow, or heavy rain preventing the runway from functioning in full capacity. This can also lead to low visibility, which can also cause planes to circle while waiting to land.
This may burn off more fuel and lead to prolonged delays in the airline’s schedule. Another weather disruption, like a winter storm, which is predominant across Europe (especially in the UK) can lead to outright flight cancellation. Heathrow is often affected because of the increased flight activities happening there.
Solution: The airport has been upgraded to Enhanced ILS (eILS) and Instrument Landing Systems (ILS) as a solution to this challenge. Airlines are guided using radio beams, which is perfect even amid dense fog. As Heathrow Airport operates Category III ILS runways, which enable aircrafts to land even in intense low visibility, these upgrades have greatly decreased the effect of fog by reducing required spacing and allowing more precise approaches.
ATC restrictions, usually caused by technical faults, e.g., radar problems at UK control centers, can cause delays or cancellations at Heathrow Airport. These hiccups in airline operations have caused a few noticeable disruptions at the airport, leading to some emergency repairs and airline grounding.
Solution: there are a few solution-driven approaches by the management of Heathrow Airport. One of which is the advanced arrival management technologies. Under this system is the Pairwise Separation, which was deployed at Heathrow in 2024. It uses a time-based separation method to adjust weather and the specific aircraft characteristics, reducing the gap between arrivals.
This new introduction has significantly boosted the airport’s operations, cutting down on the average arrival delays by 20%, peak landing rates by up to 3%, delays caused by headwinds dropped by a significant 60%, and no-delay arrivals by more than 6%.
Although Heathrow is known to have the best airport infrastructure in the world, it is not without a few challenges. Some of the known ones include power outages believed to be caused by a fire outbreak at the nearby substation (which happened sometime in March 2025). This led to a significant delay and cancellation of all flight schedules.
Another reason for flight disruption at Heathrow can be linked to cyber-attacks. The airport was reported to have had a cyber-attack incident in 2025, on Collins Aerospace: third-party check-in/boarding vendor. The attack was said to be a self-sponsored cyber-attack, which triggered a flight delay for 24 hours, since the airport was forced to switch to a manual method. It also caused a huge outright cancellation of other flights.
Solution: Heathrow and its partners are working on strengthening its infrastructure by adding cyber resilience and upgrading to more modern operational equipment to curb risk associated with technical or infrastructure problems. There has been an effort to introduce backup systems and redundancy in the airline operations. Heathrow has introduced multiple power feeds, uninterruptible power supplies (UPS), and on-site generators directly connected to IT, radar, and lighting equipment.
And for a stronger cyber system, the airport has hardened its website operations. It has deployed some physical and cyber protection equipment for its transformers and substations – in a move to fence, sensor, and suppress external risks.
These are the most effective reasons for delays and cancellations at Heathrow Airport. When airline staff, baggage handlers, and air traffic staff go on strikes, all airline schedules are affected – a typical example being the SAS Airlines crew actions in late 2025, a move that affected Scandinavian routes, disrupting its operations.
This is peculiar to UK aviation. It’s caused by factors like high living standards in London, social pressure linked to the recovery of an outbreak, as seen during post-COVID, and outsourced contracts.
Solution: The management of Heathrow has implemented some legal processes under UK law to cut the issue of strikes at the airport. However, contractors like Wilson James, unions, Heathrow, and airlines are using a few strategies to tackle these challenges. Some of them include:
There are some other factors that contribute to delays and cancellations at Heathrow Airport, which are considered minor but have a compounding effect. Some of these factors that made up the reasons are aircraft maintenance, crew rostering issues, ground handling, high passenger volumes, especially during peak seasons e.g., holidays, and summer. Others include:
Solution: Airline turnarounds are the most affected when these disruptions happen. To facilitate an effective aircraft turnaround efficiency, which is an effective move to solving issues surrounding flight delays, AI-enabled camera networks across the airport stands were conceived, with plans to achieve full coverage by the end of 2026.
This move requires using high-resolution AI-induced cameras to monitor airline turnaround activities in real time, e.g., refueling, baggage loading, passenger boarding, and cleaning. Doing this will analyze data and identify challenges earlier, fasten the process, and suggest optimizations.
The airport is also looking to achieve collaborative ground operations through its Operational Efficiency Cell (HOEC) by deploying tools like Airport Collaborative Decision Making (A-CDM), which shares data of different airlines, ATC, and handlers in real time.
Heathrow airport has improved significantly in different areas with the use of tech and other modern management solutions, especially with airline punctuality in recent times. For better information about flight operations at Heathrow Airport, passengers are advised to use the airport’s official website (FlightStats/FlightAware) for the latest updates on Heathrow Airport delays and cancellations.
However, it is also important to understand that passengers are entitled to certain compensation when their flight is either delayed or cancelled – as stipulated in European regulation 261/2004, and UK261 Regulation and several others which also applies to the UK aviation industry. Check your compensation eligibility with Click2Refund’s free compensation calculator in just minutes.