Missing grandfather had crossed Cook Strait on jetski many times

The missing jetskier who set out to cross the Cook Strait from the Tasman district on Monday is a retired grandfather who had made the trip many times before.

The Kāpiti Boating Club member vanished after setting out to cross the Cook Strait from the Tasman district on Monday morning.

Police said the man never arrived at his destination at Plimmerton Beach in Porirua.

His jetski had been found at Cook Rock, off the top of the South Island.

Club Commodore John Smith said the man had met up with friends and was getting ready to head back before he went missing.

"When he arrived there weren't any issues from what I understand."

He said the man had made the trip in a jetski many times with no issues and they were shocked he had gone missing.

"Thankfully the search people and police are out in full mode. We are just hoping he will be located."

He said the boating club was supporting the man's family.

"They are all together at the moment and putting on a very brave face."

The search and rescue operation began on Monday and police and SAR teams have been conducting a water search with the Coastguard and Rescue Coordination Centre.