NEW LONDON, Conn. – Operations to recover the wreckage of a small plane that went down in Long Island Sound have been put off until at least Wednesday morning.

Fog continued to blanket the area where the plane crashed Monday afternoon, killing all four people onboard.

The single-engine Cessna 182 was on its way from Portland, Maine, to Groton-New London Airport when it went down for unknown reasons.

Don Rich said his company, Noank Marine Services in Groton, has been contracted to recover the plane.

State police, using side scan sonar, located the wreckage Tuesday and marked the crash site for the federal investigation team.

The plane was one of 22 planes participating in the International Fellowship of Flying Rotarians’ annual “fly-about,” club member Phil Yoder said.

The planes, carrying about 70 people, left the club’s 100th anniversary conference in Chicago last week and were on a flying tour, he said.

The crash happened just before 2 p.m. a half mile from Pine Island off Avery Point, state Department of Transportation spokesman Chris Cooper said.

The bodies were recovered about 20 minutes after the crash and were taken to the office of the state’s chief medical examiner.

State police Tuesday released the names of the four people, identifying them as Herbert Rollins and Patricia Rollins of Phoenix, Ariz., and Peter Walsh and Helen Walsh of Waga, Waga, Australia. Herbert Rollins, the plane’s owner, was believed to be the pilot.

“He’s been a pilot for a very long time,” said Luncina Pyne, governor-elect of Rotary District 5510 in northeast Arizona. “This is someone who is extremely skilled, not someone who just got their pilot’s license.”

Rollins, a retired dentist who went by the nickname “Chip,” typically flew with his wife, Patricia, who was secretary of the club and also a pilot, Pyne said.

Rollins was a volunteer for Angel Flight America, a charity that provides free flights for sick people needing medical treatment, his friend, Chuck Flint, said. Rollins also volunteered with Young Eagles, a program that teaches teens to fly, Flint said.

“He’s a straight-up, straight-arrow pilot,” said Flint, who is also a pilot. “He flies by the book.”

The plane took off from the Portland International Jetport at 10:56 a.m., said Gregory Hughes, airport spokesman. It was supposed to have arrived in Groton at about 12:32 p.m., he said.

The airplane was built in 1980 and held a valid FAA certification, according to agency records.