DEFENCE officials today assured people in Suffolk that mysterious visits to the county of a low-flying Chinook helicopter were simply “routine training” and nothing sinister.

DEFENCE officials today assured people in Suffolk that mysterious visits to the county of a low-flying Chinook helicopter were simply “routine training” and nothing sinister.

There is speculation the trips by the powerful craft are top secret missions by the SAS to train at Sizewell B nuclear power station.

It could be a prime target for terrorists - and the Special Air Service is known to be playing a leading role in protecting key facilities around the country, particularly in London.

Ministry of Defence officers were tight-lipped about the twin-rotor helicopter's trips - but today the RAF said they were nothing out of the ordinary.

The £10 million Chinook came from RAF Odiham in Hampshire, home to 7 Squadron which supports the SAS and SBS on their undercover missions.

The helicopter has been a regular visitor to Suffolk this year - seen landing at police headquarters at Martlesham Heath and believed to be visiting the Sizewell B complex.

The latest sighting was over the Wickham Market area on Monday.

“It flew over about 9.45pm and I could hear it clearly - they have a very distinctive sound and I knew it wasn't an Apache,” said resident Simon Parker.

“I went outside and I could see its lights. It flew out towards the coast and I thought, I wonder where that is going.

“Ten minutes later it came back and flew over again.”

Media officer at RAF Odiham, Flt Off Leigh Shaughnessy said the aircraft, which can travel up to ten hours if equipped with internal fuel tanks and up to three hours at 150mph if not, had been on a “flight check” in Suffolk, part of routine training including flying over coastal areas and the sea.

“We try to spread the load as much as we can by travelling to train in different parts of the country because we are very aware these aircraft are big and loud and while some people find them very exciting, others don't,” she said.

“It is good for the crews to be able to train in different terrain and get them accustomed to landing at different sites and flying in different places as they would in a real situation in action rather than using the same places each day.”

Suffolk is used for 2,742 hours of low flying a year by the military - mainly over rural areas.

Military fixed wing aircraft are judged to be low flying when they are less than 2,000 feet from the ground, and helicopters below 500 feet.

Have you seen the Chinook on its travels? Write to Your Letters, Evening Star, 30 Lower Brook Street, Ipswich, IP4 1AN, or e-mail EveningStarLetters@eveningstar.co.uk

FASTFACTS: Chinook

Forces operating in Afghanistan have a shortage of Chinooks at the moment with several undergoing a multi-million pound upgrade.

But that didn't stop Prince William using one twice in a week in the spring - once to land at his girlfriend's Kate Middleton's house and the other to pick up his brother Harry to travel to their cousin Peter Phillips' stag party.

In the same period, Prince William also used a Chinook to get to a wedding in Northumbria and twice to fly over Royal residences. The total cost of these flights was more than £50,000.

In the Gulf War of 1991, Chinooks from 7 Sqn at RAF Odiham placed SAS foot patrols into Iraq and delivered SBS sabotage teams close to Baghdad.

Pilots of Chinooks - which have a crew of four, pilot, navigator and two load masters - are trained to fly a tree-top level, often at night, so they can sneak under enemy radar.

The helicopters are armed with a variety of machine guns at the rear and side and special equipment to avoid and fool attacking missiles.