Passengers told of their terror on board a Ryanair flight which lost cabin pressure after part of the plane struck the runway during take-off.

Some of the 148 people on flight FR208 from Dublin to Stansted yesterday also claimed a number of oxygen masks did not work, with some passengers having to move seats to get access to ones that did work.

Roisin Hartshorn (26), from Ashbourne in Co Wicklow, said she was "terrified" when the plane began to get into difficulty.

She and a friend were seated in the second last row on plane and were travelling to London for a weekend break.

"We were taking off and we heard a bang. It felt like the back of the plane whacked off the ground. Everyone was looking around really confused," she said of the take-off.

"After three or four minutes everything began to feel really heavy. Then it sounded like the backdoor had opened up and air started escaping from the cabin really quickly. We felt a rush of air and a whistling noise. My ears were popping like crazy," she said.

"The air hostess was running up and down the aisle. She got hold of the phone and kept screaming for oxygen."

Ms Hartshorn claims she could not open her oxygen mask, which she says was trapped in the overhead cabinet.

"Our oxygen masks didn't come down. I got a pen and tried to open up the cabinet but it broke," she told the Irish Independent.

"The guy behind us was handing us oxygen while we were trying to open the cabinet. We couldn't breath.

"The air hostess had her mask on, but she handed me her hairclip and then her ID card to try and open the cabinet and luckily it worked."

Brendan Duffy, from Dundalk, who was also onboard, said the 40-minute flight left a lot of people very shaken.

He was travelling to London to see friends.

"The oxygen masks in our row wouldn't come down at all. Everyone was really scared at that stage," he said. "Luckily the flight wasn't fully booked I don't know what I'd have done if it was.

"The fact that Ryanair are saying they were deployed correctly is not true. It wasn't a nice experience."

Rodney O'Hara (64) and his wife, Jane, also claim they had difficulty with their masks. "They just did not deploy, they weren't sure why. Luckily there were spare ones so it did not matter,'' he said.

"In fairness to the captain he came to the door of the plane when we were exiting and he apologised and said if anyone had any questions he'd be happy to answer them,'' he said.

A spokesperson for Ryanair said last night the airline had verified that all the oxygen masks were deployed. She confirmed the pilot had depressurised the cabin, but said this was a standard operating procedure.

Investigation

Air accident investigators are to examine why the cabin of a Ryanair flight depressurised and oxygen masks deployed during what was supposedly a minor incident.

Officials from the Irish Department of Transport's Air Accident Investigation Unit rushed to the scene following the emergency landing of flight FR208 at Dublin Airport yesterday after a protective cover on the aircraft's tail scraped the runway on take-off.

Some of the 148 terrified passengers on board claimed that a number of oxygen masks did not work when the cabin depressurised, with some people forced to swap seats to access the devices. Ryanair said all available oxygen masks deployed properly.

No structural damage was caused to the aircraft which will be flown to Stansted, London, later today, where it is due to be checked over by engineers.

"Tail-rubs" were "not unusual", one source said, adding that when such incidents occurred normal procedure was that the aircraft would return to the airport. The incident yesterday was not a "major one", they added.

"In the normal course of events, they (investigators) will check the aircraft and interview the crew about the deployment of oxygen masks," they said. "As a matter of course, if the oxygen masks are deployed, you have to find out why. If all of them hadn't deployed, the Air Accident Investigation officer will want to know why."

The Air Accident Investigation Unit (AAIU) would not give details of the investigation, saying they were examining an incident involving a Ryanair plane en route to Stansted airport from Dublin Airport. They were interviewing the crew, and had inspected the aircraft.

A full-scale emergency response was enacted by the Dublin Airport Authority (DAA) when the flight touched down again at 11.40am.

In a statement, the airline confirmed that the protective tailskid of the aircraft touched the runway during take-off.

"As a precautionary measure, the aircraft returned with oxygen masks deployed and landed safely in Dublin. All 148 passengers disembarked normally and will be re-accommodated in the next two flights to London Stansted," it said.

"Please be advised that all oxygen masks were available to operate -- nothing abnormal (occurred). The pilot followed SOP (Standard Operating Procedure) and conducted a controlled depressurisation of the aircraft and deployed oxygen masks."

This is not the first incident a Ryanair flight has been involved with this year.

Last March, an airliner skidded off the runway amid foul weather in the French city of Limoges. The jet, which was on flight from Brussels, overshot the end of the runway.

Last month, a Ryanair flight bound for Spain was forced to make an unscheduled landing following a loss of pressure in the cabin. Sixteen passengers were taken to hospital suffering ear problems after the incident, which involved a Boeing 737-800, the same aircraft involved in yesterday's incident.

But Ryanair last night insisted the fleet was "absolutely safe".