* Weather not thought to be a factor
* Search continues as night falls
* Union wants helicopter model grounded pending probe
* Second Super Puma helicopter crash in six weeks
By Tim Castle
LONDON, April 1 (Reuters) - At least eight people were killed and eight more are missing after a helicopter crashed into the North Sea as it returned from an offshore oil rig on Wednesday, British police said.
“From the reports that we have this seems to have been a catastrophic incident and therefore it looks like the death toll is going to be significant and the losses great,” Scottish First Minister Alex Salmond said at a news conference.
Grampian police said eight bodies had been recovered at that eight others on the Super Puma helicopter were unaccounted for.
An extensive rescue operation involving 15 ships and lifeboats was continuing as darkness fell.
Oil company BP said the helicopter had been carrying 14 passengers and two crew from its Miller platform some 165 miles (270 km) offshore.
Drilling company KCA Deutag said ten of its workers were among the passengers, of whom nine were British and one was from elsewhere in Europe.
Rescue ships spotted two overturned life rafts.
A coastguard spokeswoman said flying conditions were excellent when the helicopter went down about 15 miles (25 km) east of the Crimond coast between Fraserburgh and Peterhead just before 2 p.m. (1300 GMT).
“There is nothing to suggest the weather would have had any impact at all on the actual incident,” she said.
It was the second Super Puma helicopter crash in the North Sea in six weeks. In February all 18 people on board a Super Puma travelling to a BP oil rig were rescued after the helicopter crashed into the sea after hitting a fog bank.
The RMT union called for the helicopter model involved in Wednesday’s crash — the Super Puma AS 332L — to be grounded pending an investigation.
Both downed aircraft were operated by Bond Offshore Helicopters, which runs a fleet of Super Puma twin-engined helicopters to supply sea-based oil rigs.
“My thoughts are with the relatives of those who have lost their lives in this crash,” said Prime Minister Gordon Brown.
“It’s at times like these that we remember the risks and the dangers that people have to undergo working to meet out energy needs,” he said.
One of Britain’s worst North Sea helicopter accidents happened in 1986 when 45 oil workers died after a Chinook crashed near the Shetland Islands to the north of Scotland. (Editing by Matthew Jones)