New UK system could squeeze more capacity out of Chek Lap Kok airport

Chek Lap Kok airport could use a new method to space out aircraft landings to cut delays and allow additional flight movements, said the UK-based consultant that carried out analysis of Hong Kong's airspace and runway capacity in 2008.

National Air Traffic Services (NATS), which also provides air traffic control services to aircraft flying in British airspace, said the use of a system called Time Based Separation (TBS) at London's Heathrow airport could cut arrival delays on windy days by half. It allows aircraft to be brought in closer together according to wind speeds rather than maintaining a constant distance.

This comes as controversy over the construction of a third runway at Chek Lap Kok airport grows, with critics arguing that the current two runways have not been fully utilised and amid fears an unwillingness by Shenzhen to give up its airspace would undermine the performance of the new HK$140 billion runway.

Strong headwinds cause delays and even flight cancellations because planes landing into the wind take longer to reach the runway even if they maintain a constant speed. The overall landing rate then drops.

Andy Shand, NATS general manager in charge of customer affairs, told the South China Morning Post that TBS simply moved aircraft closer together to regain some lost landings. This can be achieved because the spirals of air generated by aircraft dissipate quicker in strong headwinds and therefore the distance between aircraft can be reduced.

"Heathrow is probably the most heavily scheduled two-runway airport in the world, so if you get any impact on the landing rate then there could be a knock-on in terms of delay and airborne holdings," he said, adding strong headwinds were the single biggest cause of delays at Heathrow.