29 March 2015
Less than a mile out from the north runway at Chek Lap Kok on March 5, strong and squally winds start to rattle Hong Kong Airlines flight 253 from Taipei.
With the sea only 150 metres below, the landing gear deployed and touchdown near, the aircraft’s engines power up, sending the plane skyward. The landing is aborted.
The pilot calmly tells passengers: “We do not have the extra fuel to re-route a second approach for landing into Hong Kong. And as such, I have decided, for our safety, we will be diverting to Shenzhen for refuelling.”
The flight was one of a dozen jets diverted that day due to a phenomenon known as wind shear. Scientists at the Observatory said the event was the worst to hit the airport since records began in 2011. Lantau is notorious for the phenomenon of rapid changes in windspeed and direction near the ground.
Passengers on Flight 253 reported that the pilot said the winds “were very, very strong”, and as such it “wasn’t safe” to make the landing.
While the weather situation was unusual, the events of March 5 also reflect an everyday problem – namely the congested skies above Chek Lap Kok.
And it is a problem that needs a solution after the Executive Council approved the Airport Authority’s HK$141.5 billion plan for a third runway that will expand the airport’s capacity.
Flight 253 was a case in point. Like other flights, it would have entered a holding pattern, a kind of highway in the skies where planes are kept apart, before the aircraft are manoeuvred, one by one, into the landing queue.
But Flight 253 was in a holding queue of 12 planes. By the time it attempted to land, it lacked the 40 minutes of extra fuel it required to “go around” and attempt another landing in Hong Kong without falling foul of the rules on minimum fuel levels. The Civil Aviation Department said the minimum fuel levels were set based on UN aviation safety rules.
Landing with good weather in Shenzhen, the aircraft and passengers waited on the tarmac for four hours before the plane was refuelled and returned to Hong Kong.
The other 11 planes also diverted to Shenzhen and Macau, while 17 landed safely at Chek Lap Kok at the second attempt.
The longer holding times – which can now stretch up to 15 minutes, according to pilots’ unions – reflect how busy Chek Lap Kok is getting.
For most of the day, the airport handles its maximum 65 flights per hour – a figure that increases to 67 per hour from tomorrow and 68 from October, the highest it can ever go with only two runways.
With 391,000 flights handled last year, the maximum capacity under a two-runway configuration, 420,000 arrivals and departures per year, is not far away.
The problem is made worse by a lack of cooperation over airspace in the Pearl River Delta, which leaves aircraft from Hong Kong unable to enter the mainland until they reach a minimum height of 4,785 metres.
Last week Chief Executive Leung Chun-ying said the central government would help to resolve airspace integration issues with Hong Kong and Macau by 2020, which could see an integration of airspace. But details of how such integration will work remain sketchy.
Airport Authority chief executive Fred Lam Tin-fuk said aviation officials and their mainland counterparts had conducted a simulation study based on a 2007 directional plan, which he said was “technically feasible”. But he shared no further details.
Pilot unions warn that unless the airspace question is resolved, more diversions are likely.
The Hong Kong Airline Pilots Association says the airport and airspace saturation problem is “further complicated” by the need to accommodate unplanned go-arounds like those on March 5.
“These additional delays can compromise planned arrival fuel [predictions] and at some point inbound aircraft will make the call whether to continue holding or to divert,” said Darryl Soligo, president of the association, which represents pilots at Cathay Pacific, Dragonair, Hong Kong Airlines and Hong Kong Express.
He said saturation in the aviation system left little capacity to deal with even the occasional wrinkle. But he warned that “pouring pavement in Hong Kong by way of a third runway is not a solution in itself”.
Airspace rationalisation is an “equally important component” and if airspace negotiations are not successful, then the Airport Authority will lose the support of a key ally – pilots.
Congestion means pilots might have to divert to airports further afield even before attempting to land at Chek Lap Kok, experts say.
Brian Legge, a wind shear expert and member of the association’s technical and safety committee, said: “Without resolving the air traffic services problems first, the result will likely be more ground delays, increased aircraft holding, and a risk of overloading air traffic controllers during periods of high volume coupled with weather or operational related challenges.”
According to the union, Cathay Pacific has acknowledged in recent years that its short-haul regional flights needed extra fuel to accommodate the time spent holding.
The number of diversions has steadily risen since 2000 – when 68 flights had to abort landing attempts.
Last year 335 aircraft had to abort landings – the second highest figure ever recorded at the airport. Some 233 were caused by weather. The rest were classified as doing so for operational reasons.
Management sources at Hong Kong Airlines said overcrowding had become “challenging” to manage. But its spokesman expressed support for a third runway, saying: “We are confident that the [Airport] Authority will make the most adequate arrangement after taking different parties’ views into consideration.”
But while the third runway is touted as the only way to increase capacity, problems do remain,
Besides airspace management, the Civil Aviation Department’s consultant on third runway matters, Britain’s National Air Traffic Service, has identified problems with escape routes – the routes that planes take after aborting landings.
And concerns remain about the cost of the runway, after a series of massive public works projects bust their budgets amid long delays. Most notoriously, the high-speed railway to Guangzhou has been pushed back at least two years to 2017, with costs rising to at least HK$71.5 billion from HK$65 billion.
One key factor in the delays and cost overruns has been a shortage of construction workers, with the industry warning it will be short of 10,000 workers within four years. The shortage and the demand from elsewhere as the government looks to stimulate public and private house building have cast doubts on the target of having the runway in place by 2023.
There is also environmental concern as the runway needs reclamation on a massive scale, further impingeing on the habitat of the endangered Chinese white dolphin.
The funding plan – under which the Airport Authority will pay for the work without seeking extra cash from the government – is also controversial. Some lawmakers are fuming because they will not get to scrutinise the budget plans, despite the fact that the authority is government owned and will stop paying dividends to the public purse.
And part of the funding will have to come from airport users including passengers, who will pay a HK$180 per person departure fee.
Cathay Pacific and Dragonair have expressed strong support for the third runway, but have cried foul over the funding arrangement, under which they would pay higher landing and parking fees.
Air New Zealand
5.50am, NZ87 from Auckland, two landing attempts before diverting to Macau
6.10am, CX829 from Toronto, aborted landing once and diverted to Shenzhen
* Cathay flights from Delhi, Taipei and Nagoya landed in Hong Kong on second attempt
China Southern Airlines
9.47am, CZ311 from Jieyang , diverted back to Jieyang
5.55am, KA932 from Manila, performed two unsuccessful landing attempts before diverting to Macau
10.07am, KA857 from Shanghai, aborted landing and diverted to Shenzhen
* Jets from Yangon, Taichung, Beijing, Zhengzhou and Shanghai aborted landings before landing in Hong Kong
Hong Kong Airlines
6am, HX774 from Bangkok, aborted landing once and diverted to Macau
6.15am, HX708 from Denpasar (Bali), aborted landing once and diverted to Macau
7.21am, HX9269 from Taipei, aborted landing once and diverted to Macau
9.53am, HX453 from Chengdu , aborted landing once and diverted to Shenzhen
2.15pm, HX253 from Taipei, aborted landing once and diverted to Shenzhen
*Three more HK Airlines jets from Macau, Taipei and Naha, Okinawa aborted landings before landing in Hong Kong
9.52am, TR2062 from Singapore, aborted landing and diverted to Shenzhen
12.03pm, TR2052 from Singapore, performed two unsuccessful landing attempts before diverting to Shenzhen
* Taiwan’s China Airlines had two go-arounds. United Airlines, Russia’s S7 Airlines, Philippine Airlines and Jetstar Asia planes aborted landings before landing in Hong Kong