weak to be taken seriously, was last night still missing in the Atlantic Ocean.

Mr. Mike Plant and his 60-foot yacht Coyote have been the subject of extensive air searches some 700 miles northeast of Bermuda since Friday.

A US Coast Guard spokesman admitted last night that "things did not look good''.

Neither the Coyote nor any life rafts were sighted during yesterday's search, which ended at 6.30 p.m. However, two C-130 planes will be sent out again today, the spokesman said.

Mr. Plant's disappearance has attracted the attention of the US media, which is focussing on the fact his EPIRB emergency signal went unnoticed largely due to the fact he had not registered it.

Canadian authorities did not know to notify the US Coast Guard that an American was involved because Plant hadn't registered his EPIRB device, an Associated Press report said. Officials had the identification number but not the name of the sender.

Mr. Plant had sent a distress signal on October 27 which was picked up by the Canadians.

They took no action because the signal had been only a short burst and not followed by any more. They also did not know who he was and the fact he was sailing alone.

Mr. Plant's venture and his custom-designed yacht were featured in this month's edition of Sailing World magazine.

Although the article did not say how much Coyote cost, it stated it was heavily sponsored by such large US companies as Motorola and had "radical'' features.

Bermuda Harbour Radio is assisting in the search by alerting all vessels in the area to keep a lookout.

A spokesman pointed out Bermuda Harbour Radio dealt with several EPIRB distress signals a day.

In the event of a sinking, the EPIRB device -- which should be kept at a yacht's highest point -- is made to float and keeps on emitting signals, he explained.

Mr. Plant, who has sailed around the world three times and won a solo race, was identified as the sender last Thursday after worried friends in Rhode Island tracked the identification number to the store where he bought the emergency satellite beacon.

Mr. Plant left New York on October 16, planning to arrive in Les Sables d'Olonne, France, on October 30.