Swanwick Software Update After 2002 Near- Miss??
Air traffic software to change after near-miss
Simon Busch and agencies
Monday January 19, 2004
GUARDIAN ONLINE
Air traffic control software is to be changed following an incident in which two large passenger jets almost collided, it was revealed today.
A mix-up at the Swanwick air traffic control centre, in Hampshire, put a Virgin Atlantic Boeing 747 and a Delta Airlines Boeing 767 on a collision course over Wales in November 2002.
A cockpit collision avoidance system alerted the Virgin pilot to the danger. As a result, the plane had to climb so quickly that a woman passenger was thrown off balance and broke an ankle.
Computer Weekly magazine today revealed that an upgrade to Swanwick software will be made by National Air Traffic Services (Nats) next month.
The magazine said that the controller in the incident thought his instructions to the pilots of the aircraft would direct the aircraft away from each other, but the opposite had happened.
It said that the pilot of the Virgin plane, which was flying into Heathrow from New York, had assessed the risk of a collision with the Boeing 767 as "high".
At one point, the Virgin plane was just 30 metres (100ft) above the 767, and separated laterally by 1.8 nautical miles - in breach of the legal minimum distance between aircraft.
According to the magazine, the controller had not realised he had mistakenly transposed identifying data on the positions of the two aircraft.
As he tried to force the jets apart, he brought them closer together. During the incident, other controllers gathered around the screen and saw the aircraft converging.
After the incident, Nats put a revised operating procedure in place. The move made controllers mindful of the potential problem, and avoided the recurrrence of a similar difficulty.
Adrian Yalland, a spokesman for Swanwick air traffic control, said that he could not confirm the Computer Weekly account of the incident.
He said the new software was being implemented in addition to the revised procedure, and added: "It's a belt-and-braces approach."
Nats today said that software changes would be made next month following "an extensive design and test programme".
The new software will change the way information is displayed on air traffic controllers' screens to make it easier for them to tell which aircraft each icon relates to, Mr Yalland explained.