UNION leaders have again raised concerns over the safety of Super Puma helicopters after one carrying 19 people to an oil rig ditched in the North Sea yesterday.

The 17 passengers and two crew were rescued after the CHC-operated EC225 came down while on its way from Aberdeen to the West Phoenix rig 32 miles south of Shetland, off Fair Isle, at around 3.30pm. The emergency has renewed safety concerns as it emerged the same Super Puma EC225 type helicopter and its older variation, the AS332, has been directly involved in a series of accidents which have led to deaths and grounding of fleets.

The worst of these was in April 2009 when an AS332L2, returning to Aberdeen from BP's Miller oil platform, suffered apparent gearbox failure and crashed off Peterhead. All 16 people on board – two pilots and 14 oil workers – were killed.

Jake Molloy, offshore organiser for the RMT union, said: "There is inevitably going to be questions and concerns and we need to provide assurances, not just to the workers but to their families, that the primary means of transporting them to and from work is safe."