DETECTIVES from Special Branch have been scouring the region's private airfields on the lookout for potential post-September 11 terrorists, it has emerged.

DETECTIVES from Special Branch have been scouring the region's private airfields on the lookout for potential post-September 11 terrorists, it has emerged.

Officers from the crack team of detectives responsible for monitoring terrorist activity have been touring flying and gliding clubs quizzing instructors about any suspicious behaviour.

Among the standard questions they have been asking was whether anyone had displayed interest in learning to take off but not about wanting to land, the EADT was told.

During a survey of clubs in Essex and Suffolk, it emerged that unannounced visits have become more frequent since the terrorist attacks on the World Trade Center three years ago.

Staff at one pilot training club in Clacton were so concerned about a couple of their would-be customers they reported them to Special Branch straight away.

But a spokesman for Essex Police last night downplayed fears the region was becoming a prime location for the aeronautical education of trainee terrorists.

He said Special Branch officers based at Stansted Airport had been carrying out routine investigations for years.

All airfields are required to submit detailed flight plans to the police and Customs and Excise officials prior to take off.

If an officer suspects anything about the flight-path or the destination, then he or she will pay the pilot and the club a visit.

While Essex has a large number of private flying and gliding clubs - as well as being home to many tiny airstrips used by hobby pilots – numbers in Suffolk have dwindled.

Richard Kimberley, who operates a small airstrip for two vintage planes in Ardleigh, near Colchester, said Special Branch visited him and his flying partner once every four months.

He said: "Prior to September 11, it used to be the Customs and Excise officials who used to question us about possible activities in their line of work, but shortly after those terrible atrocities the police started to get involved.

"Officers from Special Branch came down and they asked me I had been approached by anybody interested in learning to fly but not landing.

"I have to say though that if any instructor did have any suspicions about students not interested in landing, they wouldn't wait for a visit by Special Branch before telling the police."

A spokesman for Clacton Aero Club, which trains pilots, told the EADT that detectives had been in contact with them "for years".

He said: "In the past we have had a couple of people come down who have been suspicious. We let the police know, but whether they act upon it or not is a different thing."

Bill Stitt, chief flying instructor for the Horizon Flying Club at Monewdon, near Woodbridge, said he too had been enlisted by officers asking for help.

He was given a poster advising people how they can play their part combating terrorism, but he said so far he has not had to use the hotline number.

He said: "The aviation community keeps an eye on these kinds of things – it's in our nature to notice anything unusual.

"The question about taking off but not landing is a standard one – the police have to ask that post-September 11, but I think we're a bit more clued up than the Americans."

Victoria Pratt, junior fire officer at the Anglian Flight Centre in Earls Colne, said: "It's quite worrying that there's the potential we could be being used like this, but we haven't reported anybody suspicious so far.

"But we're always on the lookout – people can be perfectly happy and chatty when they come to register, but our instructors are trained to monitor what they are like once they're in the air."

Even gliding clubs have been targeted by the detectives. Paul Foulger, spokesman for the Essex and Suffolk Gliding Club at Wormingford, near Colchester, said a detective from Stansted Airport had left his calling card just recently.

He added: "He came here looking around asking perfectly legitimate questions and said he was going to other flying clubs elsewhere in Essex."

A spokesman for Essex Police said: "This is something that we have been doing for some time, even before September 11.

"All flight plans from private airstrips have to be submitted to us and other authorities such as Customs and Excise prior to take-off. We check them and if we think there's anything suspicious or worth a spot check, then we'll pay the airfield a visit.

"The questions that are asked to pilots and instructors tend to be more complex than simply asking whether people have been showing a lack of interest in landing a plane."