Inspections have been ordered on two North Sea helicopter types after a door fault was discovered that could prevent the safe evacuation of passengers.

The European Aviation Safety Agency (EASA) identified an issue onboard the Airbus AS 332 and EC 225 Super Pumas during a scheduled check.

An emergency door mechanism failed and an investigation revealed corrosion damage caused by undrained water.

The EASA Airworthiness Directive states: "This condition, if not detected and corrected, could lead to jamming of the door jettisoning mechanism, possibly preventing jettisoning of the affected door in an emergency situation and obstructing the safe evacuation of occupants."

Inspections have been ordered within three months for older aircraft and 15 months for newer ones.

The EC 225 was temporarily grounded after two ditchings off Aberdeen and Shetland in 2012.

Sixteen people died in 2009 when the same model plunged into the sea off the Aberdeenshire coast while returning from a BP platform.

A spokesman for the British Airline Pilots Association said: "The Airworthiness Directive has been issued as a result of an unusual failure of an aircraft to pass the jettison test and is intended to ensure that there is not a wider problem throughout the fleet by a special inspection of the jettison system.

"The jettison test is carried out on a flying hour basis and most aircraft in regular use will have it done about twice a year.

"The directive will ensure that any aircraft not in regular use is inspected within a reasonably short timescale of three months before any excessive corrosion can develop."