An automatic bar on the recruitment of air traffic controllers over the age of 35 has been declared unlawful by an employment tribunal.

The key ruling was won in a case by Peter Baker, who challenged the bar imposed by National Air Traffic Services (Nats), the body responsible for the bulk of the UK’s airspace.

Mr Baker had applied for a training position a few weeks after his 50th birthday but was automatically rejected because of his age.

He took Nats to a tribunal under the age discrimination laws, arguing that he had a strong past experience and interest in aviation and that his online application did not allow for this to be considered.

Mr Baker, a physics graduate from Imperial College, London, had a private pilots’ licence but did not have the funds to continue training as a commercial pilot and so wished to pursue a career as an air traffic controller.

The London Central Employment Tribunal has now ruled that the absolute age bar “excludes suitably qualified individuals some of whom may be marginally older than 36.”

In addition, it excludes individuals who have relevant experience and who and have shown in the past a good success rate. The tribunal ruled that this was irrational.

Nats, whose operations were formerly part of the Civil Aviation Authority, have exclusive rights to supply air traffic control services to a large part of the UK’s air space. It also provides air traffic control at the UK’s busiest airports including Heathrow and Gatwick.

Nats, which said it was “disappointed” with the ruling and was considering its options, had tried to defend its age bar on the grounds of an alleged decline in performance among older controllers.

It added that the cost of training air traffic controllers, estimated at around £600,000, was another factor in rejecting older candidates because it needed to recoup these costs through long service periods.

But the tribunal rejected these arguments saying the evidence of decline with age was insufficient and that “confusion appears to have infected [Nats'] reasoning throughout.

Daniel Barnett, an employment barrister at 1 Temple Gardens, said: “This is a high-profile example of the danger that employers face if they make assumptions about age without the evidence to back it up.”

Subject to an appeal, Nats may now be forced to revise its recruitment rules and scrap the age bar.

Mr Baker said: “I am absolutely delighted with the judgement I always thought the refusal to consider my application was a clear act of age discrimination and I am very pleased that the tribunal has agreed.”

A subsequent tribunal will award Mr Baker compensation. It cannot order Nats to give him a job although he would be free to re-apply if it changes its policy.

Gordon Lishman, Director General of Age Concern, said: “This landmark ruling shows that age discrimination has real teeth and that age-based prejudice has no place in our society.”

“The tribunal has taken a common-sense approach to arbitrary upper age limits and suggests that excluding people from jobs on the basis of age will rarely be justifiable.

UK Age Discrimination laws, introduced in 2006, bar employers from treating an employee – or potential employee – differently on the grounds of their age.

Recent disputes have involved whether people can be forced to retire at certain ages and whether someone can be too old for a “young persons” job such promoting products in a nightclub.

The law does not ban age limits outright but says they must be justified. Since the legislation gives few guidelines on what is and is not justified, the matter has been left to the employment courts to decide.

Rob McCreath, a partner at Archon Solicitors, said: “The decision is not saying you absolutely cannot have an age bar but rather that if you want to impose one, you need to have a very good reason and firm evidence to back it up.”

James Davies, a partner at law firm Lewis Silkin, welcomed the 50-page ruling saying it provided employment lawyers with a good idea of how the courts would treat age discrimination cases.

The armed forces has a blanket exemption from age laws so can impose any limits it sees fit. The legislation also contains the concept of a “genuine occupational exemption” although these are rare. Mr McCreath said an example would be allowing a theatre company looking to fill the part of an old man to refuse applications from young women.

Nats said: “Nats is disappointed by the Tribunal’s judgement. Independent research demonstrated that the skills used by controllers working in a high-performance environment decline after age 45 unless the individual has some ten years experience before that point.”

“Our only interest has been to provide a safe air traffic control service, and we will be taking time to study the Tribunal’s decision before deciding how best to move forward.”

Next week, the European Court of Judgement (ECJ) will give its ruling in the long-awaited Heyday! case which challenges the UK's right to impose a blanket retirement age of 65.

In the Nats case, Baker & McKenzie represented Mr Baker pro bono.

Nats was represented by Blake lapthorn Tarlo Lyons.

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