MYSTERY surrounds a low-flying passenger jet plane which was seen cruising over homes on the Felixstowe peninsula.The loud noise of the aircraft's engines brought people out on to the streets and in to their gardens to watch the spectacular sight – with many puzzled over why the plane appeared to be so low.

MYSTERY surrounds a low-flying passenger jet plane which was seen cruising over homes on the Felixstowe peninsula.

The loud noise of the aircraft's engines brought people out on to the streets and in to their gardens to watch the spectacular sight – with many puzzled over why the plane appeared to be so low.

But air traffic controllers and the Civil Aviation Authority say there have been no unusual incidents involving planes in the area.

The plane was seen at about 2.30pm on Saturday afternoon and appeared to witnesses to be extremely low.

One Felixstowe resident said: "It looked huge. We heard the noise and came outside immediately because we wondered what was happening.

"Usually you cannot hear the passenger planes when they go over – you only see them if you happen to be looking up at the time, and then they are so tiny because they are way up in the sky.

"This one was incredibly low and looked as if it might be in trouble. With the world situation at the moment, it just made you fear the worse."

A spokesman for the Civil Aviation Authority said: "Sometimes planes look a lot bigger in the sky than usual and may be flying lower than normal – but they are still probably 10,000ft up.

"If a large passenger plane was really low, it would be enormous and there would be no doubting how close it was."

Aviation experts say sometimes atmospheric and climate conditions can cause an "optical illusion" which makes planes appear much lower in the sky.

Another explanation could be that the aircraft was not a civilian plane but one being used by the military to ferry soldiers and airmen to and from air bases in the country – and no details would be released for security reasons.

Residents have previously reported instances of "low-flying" planes over Felixstowe but neither CAA officials or air traffic controllers have recorded any problems or difficulties on those occasions.

Before the closure of Bentwaters air base, east Suffolk rarely saw civilian flights because of the freedom of the military to use the skies for its purposes.

The closure of the base opened up the airspace and now there are a large number of holiday and business flights across the county every day.