The incident involved a United Airlines flight

Several safety recommendations have been issued following an incident on board a flight from the US to Dublin when 15 passengers and crew were injured.

The Air Accident Investigation Unit report issued today reveals several flight attendants and passengers on board the flight were lifted off the floor and seats, hitting the ceiling of the aircraft during the incident.

The United Airlines Boeing 757-200, with 131 passengers and eight crew, was en route from Newark to Dublin in October 2013.

It had begun its descent into Dublin when it was hit by severe turbulence 80 autical miles southwest of Dublin.

The co-pilot believed the aircraft was then starting to stall due to a false air speed indicator.

Twice he put the plane into a dive to recover air speed before it emerged the captain's air speed indicator was giving an accurate reading.

The flight resumed normally and the aircraft landed in Dublin.

Eight passengers and two attendants received treatment for minor injuries at the airport.

One passenger subsequently went to hospital for further treatment.

The AAIU report reveals that several days later another passenger came forward claiming he was in the toilet at the time and was injured when he hit his head on the ceiling.

Four more passengers later also said they were injured.

The report said that the aircraft had "sustained significant damage" during the incident.

Analysis of the flight data recorders by the AAIU showed that the passenger aircraft had exceeded its maximum certified airspeed by thirty knots during the incident.

Following its investigation the AAIU concluded that the probable cause of the false instrument reading was icing of the pitot tube which the co-pilot used to gauge the speed of the aircraft.

However, the report also said the crew responded in a "non standard" way to the airspeed warning and that the "startle effect" by the flight crew was a contributory cause.

The report makes a total of eight recommendations to United Airlines generally referring to changes to flight training as well as Boeing and the Federal Aviation Authority about the dangers of protection from icing and instruction material for flight crews when instruments give conflicting readings.

http://www.rte.ie/news/2016/0510/787420-flight-safety-recommendations/