Why do planes ‘Go-around’?

On Saturday afternoon, as storm clouds built up over Central Nepal, three international flights performed Go-arounds at Kathmandu airport.

A Qatar Airways Airbus A330 from Doha, a Boeing 737 Max of FlyDubai and an Indigo Airbus 320 from Delhi. All three reported tail wind and wind shear at the threshold of runway 02.

Nepal’s media characterised these as ‘near-misses’ – as if the planes were almost having a mishap. Actually, a Go-around is very common at airports around the world and shows that the pilots take safety seriously and abort a landing if the approach is not stabilised.

A Go-around is when an aircraft on final approach suddenly climbs again on full power instead of landing and circles around for another attempt. This is a standard safety procedure in aviation, even though it may alarm some passengers. Go-arounds are also called ‘missed approach’ or ‘overshoots’.

The International Air Transport Association (IATA) notes that go-arounds are an important part of flight safety, allowing pilots to avoid potential hazards on the runway, the surrounding airspace, or if there is high wind or poor visibility.

Globally, 3% of all landings by commercial aircraft are Go-arounds, showing how they are common and preventive measures rather than emergency responses.

Pilots usually initiate a Go-around if the approach is unstable due to wind or turbulence. A stable approach means maintaining the correct speed, altitude, and descent rate for a landing. If these factors are not optimal, pilots may opt to go around as a precaution.

Sometimes pilots decide to go around if there is a runway obstruction, which can be another aircraft, vehicle, debris or bird activity on the runway. But the most common reason for planes to go around is weather-related: sudden changes in weather, such as strong crosswinds, heavy rain, or poor visibility.

Kathmandu’s Tribhuvan International Airport is surrounded by high terrain that requires a steeper than usual approach for landing. This time of year, there are high winds especially in the afternoons with cloud-build up and turbulence.

Heavy aircraft like the Airbus 330 or Boeing 777 or 787 that operate in Kathmandu cannot land when the tailwind is more than 12knots, and this has been the case most afternoons in the past month. However, a Qatar Airways Boeing 787 performed the first ever satellite GPS-based RNP approach to runway 20 from the north earlier this month.

During rush hour at Kathmandu airport, Air Traffic Controllers are under pressure to handle a large volume of arrivals and departures. Earlier this year the airport handled over 600 international and domestic flights in one day, and because the airport is closed for 8 hours a day due to runway grading work there are delays.

ATC sometimes instructs pilots to go around due to congestion or delays in clearing the runway from a previous landing. However, with the completion of the parallel congestion is expected to reduce after 1 April when the airport will be opened again for 20 hours a day.

Go-arounds can also happen if the pilots detect a last-minute technical issue, such as an indicator light malfunction or landing gear irregularity. They will go around and troubleshoot before another approach.

Nepal’s unique topography makes flying challenging, especially in high-altitude airports. Pilots operating in Nepal frequently undergo specialised simulator training for terrain-based approaches and learn to execute go-arounds safely in difficult conditions.

The Civil Aviation Authority of Nepal (CAAN) has continuously worked to improve navigational aids and approach procedures to enhance safety. Buddha Air, Nepal’s leading domestic airline, for example ensures that all its pilots are well-trained in go-around procedures.

As aviation technology continues to advance, automated systems assist pilots in making more precise go-around decisions, further ensuring safe landings. Whether due to weather, air traffic, or technical reasons, they are always executed with the passengers’ best interests in mind.