Power cut halts Belgian airspace until at least 4 p.m.

Zaventem Brussels Airport, October 25, 2010. (photo: Ad Meskens / Wikimedia Commons)Zaventem Brussels Airport, October 25, 2010. (photo: Ad Meskens / Wikimedia Commons)

With reporting by Zack Newmark and Taneli Savela.

An electrical failure at Belgium air traffic control forced the closure of airspace above Belgium on Wednesday morning, Eurocontrol said in a statement. The regional airspace will remain shut until at least 4 p.m. local time, the Brussels Airport authority and Eurocontrol both said.

Just over 60 flights were cancelled, and 21 were diverted, the airport said at about 11:40 a.m. There were 10,176 departures from the airport, and 10,193 landings last ,onth. In 2013, the Brussels Airport authority estimated that 510,000 passengers based in the Netherlands use the capital city airport.

The electrical failure is causing significant delays, according to the airport authorities. "A number of flights are being diverted to airports in the neighbourhood," they stated.

The cause of the problem was not yet announced. Wednesday morning marked the beginning of a three-and-a-half month long project to renovate runway 25L at the airport.

Dutch air traffic control reports that some of the Belgian flights will land in the Netherlands. Flights that had to cross Brussels airspace on the way to the Netherlands can reroute via Germany or the North Sea.

Only planes flying at high altitudes above Belgium that do not have to land in the country can continue their journey over it. Those are handled by air traffic control in Maastricht, and not workers in Belgium.

The power blackout began at 9:30 a.m. This is the first time such an electrical problem caused so much trouble for Belgian airspace, a Flanders regional broadcaster reported.

In March, a large power outage in Noord-Holland and Flevoland brought Amsterdam Airport to a standstill. The power loss lasted for 1.5 hours and resulted in cancellations and diversions for many Amsterdam flights.