Incidents of violence by air passengers towards cabin crew almost doubled in 2007-08, it was revealed yesterday.

And the total number of "significant" incidents of disruptive behaviour by passengers increased from 2161 in 2006-07 to 2671 in 2007-08, according to the Civil Aviation Authority figures published.

However, incidents classed as "serious" fell from 58 to just 31 - the lowest figure for four years - in the data released by the Department for Transport.

The statistics showed the number of reported incidents of violence towards cabin crew rose from 58 in 2006-07 to 99 in 2007-08.

But during 2007-08, no case was reported in which disruptive behaviour contributed to an aviation accident.

Alcohol consumption and smoking were the main contributory factors in 63% of reported incidents.

Aviation Minister Jim Fitzpatrick said: "It is good news that serious incidents are at their lowest for some time - but one act of unruly behaviour is still one too many.

"In recent years we have introduced much tougher maximum penalties for people acting in a threatening or disruptive way on aircraft. Disruptive behaviour is completely unacceptable and our primary concern is to protect the safety and welfare of passengers and crew.

"I am pleased that reporting of incidents continues to improve and that airlines are also taking a firmer line in dealing with any disruption. We want everyone to be able to fly without fear of disruptive behaviour."

Of the incidents, 74% involved male passengers and 26% involved female passengers. People in their 20s were the main offenders, although the age of offenders was only given in 21% of all cases. There were 31 reports of incidents involving groups of 10 or more people.

The increase in the total number of incidents reported is against a backdrop of more flights and more people flying.

In 2007-08, UK airlines participating in the reporting scheme carried 124 million passengers on one million flights. This compares to 121 million passengers carried on slightly fewer flights in 2006-07.

In October this year, a flight from Glasgow to the Canary Islands was forced to divert to Portugal so that police could detain three rowdy passengers.

A couple and their son were turned over to authorities in Faro, before the Thomas Cook flight could continue to Fuerteventura.

They were arrested, but later released.

In an earlier incident, a Scottish oil executive was fined £750 after a whisky-fuelled disturbance on a flight to Aberdeen during 2003.

Charles Hughes, then 38, admitted at Aberdeen Sheriff Court that he had shouted "We are going to die" during the flight, after swearing at a stewardess, beating violently on the rear emergency doors and demanding alcohol from cabin crew.

As far back as 2003, A Scottish MP called for legislation to curb the number of so-called "air rage" incidents involving the British public.

Frank Roy, MP for Motherwell and Wishaw, raised the issue in parliament after a stewardess was attacked with a bottle on a flight to Malaga.