Airlines should be more open about the extent of air rage incidents on flights if they are serious about reducing the number of disruptive passengers, according to two pilots' associations.

Capt Frank Feeney, security spokesman for both the Irish Air Line Pilots' Association and the International Federation of Air Line Pilots Associations said many airlines were reluctant to publicise such incidents.

"They are afraid to admit there is a problem there. Most airlines don't really mention it. They take it as a public relations problem rather than a security problem. If they would view it as a security problem I think a lot of the incidents would be sorted out quicker," he said.

Capt Ted Murphy, president of the International Federation of Airline Pilots' Associations, said it was "unfortunate that statistics on levels of disruptive passenger behaviour are not kept in Ireland. They keep statistics in the UK and the US. We don't have such a thing in Ireland, which is unfortunate. We would certainly encourage reporting throughout the world," he said.

"Until recently, there was a tremendous denial of the problem. Airlines are in the business of selling seats to passengers, so naturally they will tend to avoid saying they have a problem, but the fact is it is a worldwide problem and they do."

One of the major airlines which provides long-haul flights out of Dublin, Delta Airlines, would not say how many incidents had occurred in the last year.

Ms Olivia Cullis, Delta's London-based manager of corporate communications, said: "We don't give that sort of information out. It's just not company policy." However, she added that the company had adopted a "zero tolerance" approach to disruptive behaviour during flights.

Ryanair's commercial director, Mr Michael Cawley, said such episodes were rare on his company's flights.

"One incident of a serious type happened about 12 months ago, but that was only one in the last five or six years. Charter people with long-haul flights tend to have difficulties because drinking is more frequent there. We don't have the kind of experience that you would think is happening on the charter airlines," he said.

Aer Lingus's corporate affair executive, Ms Suzanne Cross, also said that out-of-control behaviour was infrequent. "We don't have that many incidents. Bearing in mind the number of passengers has risen so considerably in recent years, obviously the number of incidents will rise," she said.

The safety of passengers was the company's priority, and Aer Lingus would take a "very hard line" with anyone jeopardising that level of safety.

While Irish airlines do not keep a record of the number of disruptive incidents on fights, their British counterparts have reported all such occurrences to the Civil Aviation Authority since April 1999, at the request of the Department of Environment, Transport and the Regions.

The latest available figures cover April 1999 to March 2000, during which 1,205 incidents were reported, ranging from the relatively minor to more serious instances of misbehaviour.

Statistics in the report offer a profile of the "typical" disruptive passenger, with more than three-quarters of the incidents involving males, about two-thirds of whom were in their 20s or 30s. One-third of incidents were instigated by people travelling alone.

Alcohol was named as one of the two main contributory factors to disruptive behaviour in the analysis of British incident reports. The other was smoking or the desire to smoke.

In about half the cases alcohol was identified or suspected as a contributory cause, although the report stresses that this may be an underestimate. Almost half of these incidents involved passengers drinking their own alcohol rather than beverages served by the airline.

Ms Cross, of Aer Lingus, outlined the company's policy on offering complimentary drinks to passengers.

"The cabin crew offer one drink and then customers are entitled to ask for a second. If they ask for a third the cabin crew will say `We'll come back to you on that one' and will wait for some time. The person may feel they have drawn attention to themselves and may not ask again. If the cabin crew thought they had had enough drink already, they would not be served."

She said the amount of drink on board differed from one aircraft to the next and was the responsibility of the catering company hired by the airline. "In terms of what would be used on a specific flight yesterday, I wouldn't have that information," she said.

Ms Cross said ground staff were trained to identify intoxicated would-be passengers and prevent them from boarding aircraft.

"If somebody is found not to be in full control of themselves, we will have a longer chat with them and the duty manager will be called and they will be assessed," she said.

On Ryanair flights, where drinks are sold to passengers, drunkenness is rarely a problem, according to Mr Cawley. "In practice, we rarely sell more than two drinks to a passenger, but if somebody had two drinks and looked sober they would be allowed another, although that rarely happens," he said.

"On an average flight we might sell 20 cans of beer and we sell the odd gin and tonic, maybe five or six. We sell very little wine. We have fairly short flights so you'd want to be a fairly active drinker to get drunk. The cabin crew have a discretion that if somebody would be going over the limit they can and will refuse drink to them. They get specific training for that."

Mr Cawley said he could not reveal how much alcohol was boarded on to an individual flight, noting that it was "commercially confidential information".

Delta's Ms Cullis said: "I don't think it's something we even monitor. It's not something I've seen in the three years I've worked here. It would very much depend how many passengers are on each flight and how many were drinking."

However, the abuse of alcohol is not the only factor which needs to be addressed as a matter of urgency, according to the Irish pilots' association. It is looking for tougher legislation in four main areas: smoking on board the aircraft; penalties for disruptive passengers; interference with crew members and the use of mobile phones and personal electronic devices on board aircraft.

Capt Feeney said changes must be introduced to the Aviation Regulation Bill, 2000, which is due to come before the Dail in October. "The Bill hasn't really taken into account our point of view and what we are seeing at the coal face," he said.

On one of Capt Feeney's flights a male passenger unsuccessfully attempted to set fire to the girl sitting next to him by throwing vodka over her and then flicking matches at her.

"Every day there are people smoking in the toilets on Atlantic flights. There was a case in the US where a chap defecated on top of a cart at the back of the aircraft. There are sexual assaults on board, as well as physical assaults," he said.

Capt Feeney said the International Civil Aviation Organisation and the pilots' associations were working on international aviation legislation. It is hoped that this legislation will bring an end to loopholes in the law which allow disruptive passengers to escape prosecution because they, or the aircraft they have flown in, are from a different jurisdiction from the place in which they land.

However, Capt Feeney said, it could take three years before this legislation came into place. "That's a long time to wait, but there is a golden opportunity for our Government to slot our proposed changes into the Aviation Regulation Bill," he said.