Four weeks after a fatal mid-air crash killed 71 people, the Swiss air traffic control agency, Skyguide, is again operating at full capacity.
Skyguide said on Monday it was now operating at 100 per cent capacity after cutting the number of flights it handles by 20 per cent in the immediate aftermath of the tragedy, which occurred in Swiss-controlled airspace.
The reduction led to severe delays at Zurich airport, but congestion has eased as Skyguide gradually increased its capacity.
A spokesman said operations had been scaled back for safety reasons and the need to relieve staff who were under severe stress. Last week, Skyguide said the controllers had received support from specialists and were now ready to take on a heavier workload.
At least two controllers
The company, almost wholly owned by the government, has been ordered by the Federal Office for Civil Aviation to make sure that at least two controllers are on duty at all times.
Shortly after the crash, it emerged that a lone air traffic controller was on duty, battling with technical problems, when the two planes collided 11,000 metres above Lake Constance.
Switzerland last week said it would be reviewing its civil aviation safety system in the wake of the crash. A final report is expected by the beginning of next year.
The transport minister, Moritz Leuenberger, said independent aviation specialists - probably from Germany or France - would be charged with carrying out the review.
The independent assessment is aimed at improving air traffic control and its efficiency, as well as reinforcing international cooperation.
Skyguide has been criticised over the collision between a Russian passenger plane and a DHL cargo jet over Lake Constance, in which 71 people died, including 45 Russian schoolchildren.
No one has been officially blamed for the accident pending the results of official inquiries, although legal proceedings have been launched in Switzerland and Germany against the lone traffic controller on duty in Zurich when the collision happened.
swissinfo with agencies
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