UK aviation regulator the Civil Aviation Authority has dismissed a complaint by Ryanair and London Stansted that company that runs air traffic control had discriminated against the airport.

After receiving the complaint the CAA launched an investigation into claims that NATS had breached its air traffic services licence and the Transport Act 2000.

The regulator said this was the first time it had used its investigatory powers under section 34 of the Transport Act 2000, reflecting the seriousness of the complaint.

National air traffic control was investigated under its corporate identity NATS (En Route) Plc (NERL).

Ryanair and London Stansted claimed NERL had failed to meet demand for services to airlines by failing to provide adequate resources to manage the performance in the London Terminal Manoeuvring Area (LTMA) and had discriminated against traffic landing at London Stansted Airport.

The CAA concluded no compliance breach has been found, however it identified areas for improvement.

Among those are improvement to NERL business practices including improving the resilience of its operations and contingency planning.

The CAA said it will also increase its oversight of NERL to address resilience issues.

Richard Moriarty, director of consumers and markets at the CAA, said:  “This is the first time that the CAA has used its investigatory powers under the Transport Act 2000 and highlights the potential seriousness of the complaint raised.

“In this instance, our investigation has found no compliance breach, however improvements to operational resilience are key to ensuring service delivery levels are maintained in our increasingly busy airspace.”