Almost one year on and here we are again.

Part of the roof of the Beijing Capital International Airport's Terminal 3 was ripped off by the strong winds that swept through the city on Nov 22. This is the second time the terminal's roof has been damaged by strong winds. The previous occasion was in December 2010.

The airport's information center said emergency repairs had already been carried out and safety was not affected.

But it is worrying that for two consecutive years the roof of Terminal 3, one of Beijing's landmark buildings, has been damaged by strong winds.

The incidents can't help but cast doubt on the construction quality and safety of one of the world's largest buildings.

A director with the airport's expansion construction department once claimed that the terminal's roof is designed and built to withstand once-a-century winds.

The wind, however, has been honest enough to show how hollow that boast was.

Although the incidents have not affected the safe running of the airport, we are concerned that it is a potential safety hazard - one that should not be ignored.

After the incident last year, the airport blamed "a weak point" on the roof, which you would think they would have seen fit to remedy. Nature has already warned us twice, we may not get a third.

The airport management must answer the following questions to ease the concerns of the public: What was the reason for the incidents? Was there any investigation and remedial action after the first incident? Was anyone found accountable?

Clearly the public is entitled to question the quality of construction and the competence of those handling the problem.

The airport management should give the public a reasonable and clear explanation of how lightening has managed to strike in the same place twice, especially as the airport is a showpiece for the city and the nation.

Such problems are not unique to the capital airport. This summer, the newly built Nanjing South Railway Station suffered leaks in the roof and land subsidence. However, such obvious quality problems were explained as "normal weather checks".

The emergence of problems in such large-scale projects can perhaps be excused, but the attitude of not treating a problem as a problem is, quite frankly, alarming and inexcusable.

Only through responding to public concerns about the quality of construction, honestly owning up to flaws and effectively remedying their causes can the airport regain the trust of the public.

In fact, the public's concerns are simple: Will the roof come off again, and if it does, what's to prevent a serious accident?

Of course, we hope it never happens again, but unless the problem is treated seriously, nature will give us the answer we don't want to hear.

(China Daily 11/25/2011 page8)