Two fishing boats and members of the local community were also involved yesterday.
RCC mission co-ordinator Keith Allen said the missing man was known to be wearing a wetsuit and lifejacket.
"We are searching the in-shore area to check he is not clinging to crayfish pots, and the Orion is also checking an area of up to 90km [50 nautical miles] offshore," Mr Allen said.
Local Ed Holter had been out twice to search for Mr Kiel, who he described as "a really, really nice man".
Mr Holter, also a fisherman, said the conditions yesterday had been terrible.
"I go out fishing but I would not have been out yesterday," he said.
"It was a very strong offshore wind and a very choppy sea. The sea was a washing machine.
"His age was against him, the sea conditions were against him and the wind conditions were against him."
Mr Holter said there was little hope of finding the man alive.
"We've done a shore search along here but the tide was actually against us and the time period that's elapsed hasn't allowed enough time, if the body is down there, for the gases to bring the body back up," he said.
Mr Kiel's dog was found by his vehicle yesterday morning. It's thought he had taken the dog with him on the boat.
"They couldn't have been too far out for the dog to have swum back," Mr Holter said.
He said local search efforts could have begun earlier had the community been notified sooner.
"The first I knew about it was that someone had seen it on the internet but none of the locals were rung, to my knowledge.
"Just about all the permanent [people] living along here have had a share in looking for him," Mr Holter said.
South Wairarapa district council coastal ranger Colin Olds agreed hope of finding Mr Kiel alive was fading fast.
"The family have established themselves here and are hunkering down until they get a result," Mr Olds said.
A Martinborough man, who did not want to be identified, said Mr Kiel was well-known in the community. "Everybody on the coast knows him more or less, he's been here for many years."
He said Mr Kiel was an experienced fisherman but Sandy Bay was a difficult place to launch from. "If it's not a very nice day you don't have to be very far out this coast to get into trouble.
"They are all crossing their fingers but it's [been] too long now," he said.