Change in plane direction surprises Bangkok residents

It’s a bird! It’s a plane! It’s… it’s… oh, wait, it *is* a plane. Residents in Bangkok have been complaining about a sudden increase in commercial planes buzzing low over their homes. Now they finally have an explanation for why they are seeing all these low planes – an airport direction change.

The Aeronautical Radio of Thailand (AEROTHAI), the agency operating under the Ministry of Transport that is in charge of air traffic control in the country explained the surprising change in flight patterns. As it turns out, Thailand’s cold season has started, and with it, the direction of the wind changes while gusts also strengthen.

With the change of airflow, Thailand’s two airports, the main hub Suvarnabhumi Airport and the low-cost secondary hub, Don Mueang International Airport, have swapped the direction for planes taking off and landing on their runways. The switch took place on Saturday and Nation Thailand reported that people quickly began to notice.

With the direction exchange, Bangkok residents will be much more likely to see low-flying planes passing through the downtown skyline according to AEROTHAI, the country’s air traffic regulators since 1948. People caught off guard by the influx of aircraft low in the sky should know that, like daylight savings time in reverse, the runway directions switch at the onset of winter and return to normal in February.

The switch is a necessary safety precaution for planes as they battle winds that change direction and pick up speed in the winter months. The prevailing northeasterly winds get stronger, blowing up to 10 to 15 knots, which is about 20 to 30 kilometres per hour, and change their course.

Don Mueang International Airport swapped out runways for safety, pausing flight traffic on Runway 21 and activating it on Runway 03. Authorities note that if winds fall below 18 kilometres per hour consistently, Aero Thai will evaluate whether or not to switch takeoff and landing directions back to their normal configuration.