An airliner narrowly avoided a collision with a microlight plane on its final approach to Norwich Airport. Now tighter controls could be placed on Norfolk's growing number of hobby fliers.

An airliner narrowly avoided a collision with a microlight plane on its final approach to Norwich Airport, it emerged last night.

Now tighter controls could be placed on Norfolk's growing number of hobby fliers who are currently not even obliged to warn air traffic controllers when they intend to fly.

Details of the near miss or 'airprox' were not made public at the time of the incident, in July 2007.

But a Civil Aviation Authority report, obtained by the EDP using Freedom of Information (FOI) laws, says the pilot of a commercial jet spotted an unidentified microlight 200m directly ahead on what he perceived to be 'a direct collision course'.

It adds: 'He immediately took control of the aircraft, disconnected the autopilot and carried out an avoiding action descending left turn as the microlight passed about 100ft directly above them with a 'high risk' of collision.'

The De Havilland Canada DCH-8 , which carries up to 40 passengers, came across the Pegasus Quantum microlight 11 miles north-west of the city, near Swanton Morley .

The so-called airprox board, which investigated the incident, concluded: 'The safety of the aircraft was compromised.'

Under the current rules microlight pilots are under no obligation to inform the increasingly busy airport when they take to the skies.

But a number of provincial airports, including Norwich, are pressing for tighter controls on the airspace around them - including making fliers notify them if they intend to take off nearby.

Norwich currently only has 2.5 nautical mile radius and 2000ft which is controlled by Norwich Air Traffic Control.

The surrounding airspace is uncontrolled and flight by any aircraft is legally permitted.

The proposed control zone is designed to extend seven nautical miles east and west, five miles north and south and extend from the surface to 6000ft.

A spokesman for Norwich Airport said 'With regards to the incident on July 31 2007, such an incident would become less likely if we had controlled airspace.

'This incident happened in airspace we are seeking to protect so that the microlight would not have been permitted in that airspace without an air traffic control clearance and hence the controller would have known it was there.

'In the airprox the controller was not talking to the microlight nor was it showing on the radar display and hence was unaware of its presence.'

Norwich Airport, which handles more than 50,000 flights a year, wants pilots wanting to fly nearby to obtain clearance from air traffic control.

Before an airport can become a controlled airspace an 18-month consultation with others using the airspace must take place.

But last night one leading microlight enthusiast said many hobby filers preferred the freedom of 'unrestricted' flying.

Chris Gurney, operations manager at Northrepps airfield said: 'Some microlight pilots don't or won't use radio but in time they will accept that all inbound traffic will have to call.

'Many microlighters however, like the idea of virtually unrestricted flying - its half the fun.

'Sadly we all have to move forward but if every airport were to follow - every sport flyer will find eventually that the restrictions are so great that the sport will die and as a result 1000's will lose their jobs and businesses.'

Richard Pace, operations director at Norwich Airport said: 'Controlled Airspace will allow us to manage safely the future growth of passenger aircraft movements and create a known environment to enable all local airspace users to jointly operate.'

There are around 2,000 microlight owners nationally and it is estimated there are around 50 in Norfolk.