Heathrow jumbo was a split second from disaster

Air safety chiefs were warned yesterday that they were courting disaster after a report revealed that two airliners, with a total of 470 passengers on board, came within a split second of a devastating collision.

In one of the worst near misses seen at Heathrow airport, a Boeing 747 jumbo jet coming in to land missed an Airbus A321 preparing for take-off by little more than 100 feet. A report from the Air Accidents Investigation Branch (AAIB) said the potentially disastrous situation had developed at a time when a controller was supervising a trainee.

Kieran Daly, a specialist in aviation, said the incident in April last year was one of the most serious of its kind, and warned that near misses would happen more often unless congestion was eased. "We have reached a stage now where UK airports are operating at the absolute limits of their capacity," he said. "The result is a system where if something fairly small goes wrong, then the consequences can be very nasty indeed."

Mr Daly, the editor of the internet website Air Transport Intelligence, called for a government inquiry into congestion in the skies. He said near misses were rarely investigated by the AAIB. "It has to be extremely serious before the AAIB becomes involved, so by definition this was one of the most serious near misses," he said.

Iain Findlay, the national official at the air-traffic controllers' union IPMS, said his members faced "many stresses" and added that there was a "dire need" for more trained controllers. "We are happy to co-operate with these reports to enable us to learn from errors made and ensure procedures and training are correct for the controllers concerned."

Mr Findlay pointed out that AAIB investigators had reported recently that an incident at Manchester airport last September had "all the hallmarks of a controller working under stress". Yesterday's report said the supervisor who was blamed for the near miss at Heathrow was also responsible for a potentially dangerous incident in 1999, and had been demoted to an airport handling fewer flights.

The AAIB inquiry discovered that the trainee, a 28-year-old woman, was initially in charge of the airliners' movements, but that her experienced colleague intervened when it became clear the situation was "tight". However, the 35-year-old male supervisor pursued the same course of action by calling on the A321 belonging to BMI ­ formerly known as British Midland ­ to take off immediately. He quickly realised, however, that it would not clear the runway in time so he ordered the British Airways Boeing 747, flying in from Japan, to pull up. The fuselage of the jumbo jet ­ with 381 passengers on board ­ came within about 112 feet of the tail fin of the airliner on the ground, which was bound for Brussels with 89 passengers.

Investigators attached no blame to the trainee. Her mentor had allowed a situation to develop in which the British Airways plane could not be "safety integrated" with the departure of the bmi aircraft. Although the incident happened in broad daylight, the Airbus was not as visible as it should have been because the "strobe lights" on its wings and nose cone were not switched on. The report recommended that the Civil Aviation Authority (CAA) should issue instructions that the lights should be on even when an aircraft is not airborne. The CAA should also ensure an adequate level of briefing and debriefing of student controllers, the report said.

National Air Traffic Services (Nats) has since introduced a more formal system for appointing personnel who supervise trainees. The experienced controller had been selected as an instructor, but had said that he did not particularly enjoy the job. He was involved in an incident in April 1999, in which he cleared a Boeing 757 to cross the runway in front of a Boeing 747 ­ but a collision was avoided after the pilot of the departing aircraft queried his clearance, the report said.

Nats, which is now part-owned by British airlines, said it "fully accepted" the report, which was "thorough" and "detailed". The air-traffic controller blamed for the incident had been transferred from Heath-row to work at a "less busy unit", and was no longer involved in the training programme, according to a statement from Nats.

"This was a very serious and regrettable incident, from which the safety lessons have been learnt and applied both systematically and individually," a spokesman for Nats said. He added that it was a "rare error of judgement".

Last year the organisation handled a record two million air-traffic movements and there were only six "risk-bearing" incidents attributable to Nats, the spokesman added.

He pointed out that the official report said investigators were satisfied with the operating procedures at Heathrow and that it had made no recommendations to Nats. "However, immediately following the incident, Nats introduced a more formal system of selecting controllers for its on-the-job training programme at Heath-row airport as well as monit-oring individual performance.

He said: "Nats believes its air-traffic control systems and procedures, approved by the safety regulator, are safe and its safety record among the best in the world."

A BMI spokeswoman said the company was "satisfied" with the report's conclusions. She added: "BMI will continue to work closely with all regulatory bodies including Nats in order to improve the high levels of safety that are currently provided."

A BA spokesman said: "Our crews regularly train for such manoeuvres. We have co-operated fully with the AAIB, which has confirmed that our crew complied with all air-traffic control instructions."