The flight information display system breakdown on Sunday forced airport staff to write departure times and gate numbers on whiteboards with marker pens, but some passengers, unfortunately, missed their flights due to the upheaval.

It was not until 7.20am on Monday that the airport announced it had restored all real-time flight data for on-site digital screens, as well as on its website and mobile app.

The events on Sunday came on the heels of an incident on Monday last week in which a cargo plane shut down one of the airport’s runways for more than eight hours after bursting two tyres during an emergency landing, resulting in delays to about 450 flights.

Lee said the Transport and Logistics Bureau met senior management of the Airport Authority to discuss the causes of the latest incident and the immediate actions taken.

The government asked the airport operator to thoroughly investigate the system failure, review contingency plans and suggest ways to prevent similar incidents from happening again.

“We have asked the Airport Authority to conduct a comprehensive review of the system, including its backup system, to upgrade its capacity in activating the system and to review its risk management measures amid the completion of the third runway system,” Lee said.

“I must again emphasise that Hong Kong International Airport forms an important part of the city’s competitiveness. It is our aviation hub and we have to provide high-quality and stable services to our passengers.”

IT experts earlier told the Post that the authority’s response time was unacceptable because computer systems should be monitored round the clock.

They added that the contingency plans lacked a human-centred approach and also highlighted the authority’s lack of effective response and crisis management preparedness.

Separately, Lee pledged to follow up with energy firm CLP Power following the voltage dip on Sunday morning.

The city recorded at least four voltage dips this year, all of which were related to CLP Power, which supplies electricity to Kowloon, the New Territories and most of the city’s outlying islands.

“Although preliminary investigations suggested the reason was unstable weather, CLP Power must ascertain the exact cause … it should tackle the problem at its root and reduce the chance for similar incidents to happen again,” he said.

Lee added the government had asked CLP Power to identify the causes, formulate improvement plans and submit a detailed report within four weeks.

The Electrical and Mechanical Services Department earlier pledged to form a task force to review and follow up on the utility’s improvement plans.

Secretary for Environment and Ecology Tse Chin-wan also asked the supplier to enhance the ability of its power supply to withstand inclement weather.