SPRINGFIELD, Vt. (AP) – An airboat that sank and caused an injured woman to drown is likely the first time a person has died during an airboat rescue in this country, experts said.

“We all knew it was coming,” said Philip Walters, head of the Florida Airboat Association, a trade group. “It was just a matter of time.”

Experts questioned crew members’ decision to strap Virginia Yates, 64, of Rockingham to a backboard and rescue gurney on the hull of the Cornish, N.H., rescue boat when they were transporting her across the Connecticut River.

The litter should not have been attached to the boat’s hull, said Robert Dummet, head of the Florida Airboat Association’s safety committee, who helped organize a group of airboats that rescued thousands of New Orleans residents during Hurricane Katrina.

Airboats are prone to taking on water or swamping, and when they do they sink within seconds, experts said.

The boats are increasingly used by inexperienced operators, Walters said.

Operators must be alert to the boat’s tendency to swamp, said David McClain, of Alumitech Airboats Inc. of Orlando, Fla., one of the country’s largest airboat producers.

“That’s why they don’t put seat belts on airboats,” he said. He said he knows from experience.

“I killed my own dog. I tied him to my boat to keep him from jumping out. You can’t do that. You can’t tie any human being or a dog to a boat,” McClain said Friday.

Yates had slipped on a dock and hit her head and twisted her ankle earlier in the afternoon. Rescue crews strapped her to a backboard and rescue gurney on the boat. She went under when the boat capsized. Rescuers tried to save her, but could not.

The New Hampshire Marine Patrol and the Sullivan County, N.H., attorney, who oversees criminal prosecutions, are investigating the accident.