It happened Thursday at Madeira Beach, near St. Petersburg.
Beachgoers grabbed hold of a snapped parasail cord and reeled them in. It took as many as 100 people about 30 minutes to pull 16-year-olds Chelsea Waddell and Theresa Blaneford down to the beach against strong winds.
"Didn't have a scratch on 'em or anything," said beachgoer Chris Dean. "So they were fine."
Waddell is the daughter of Atlanta Thrashers general manager Don Waddell.
"We were on top of a bunch of buildings, over streets and roads, and it was really freaky," she told a local TV station.
When the Get Wet Parasail company's boat stalled on its way toward the Gulf of Mexico, the tow line attached to the parasail's passenger seat snapped. The wind immediately carried them across the beach and over a line of condominiums and hotels.
Parasail boats and operators are inspected and regulated by the Coast Guard, but there are no inspection requirements for parasail equipment such as harnesses and tow lines.
The Tampa-St. Petersburg area has seen parasailing tragedies: In December 1990, a man died when the boat operator cut his tow line because the winds were too high. He eventually fell head first onto a tennis court. In 2001, a 13-year-old girl and her mother were killed when a parasail harness broke, dropping them more than 20 stories.
Cheryl Waddell noted the high winds when she dropped her daughter and Blaneford off at the parasailing business. She told the St. Petersburg Times she repeatedly asked company employees whether it was safe, and was told it was.
"The pressure of the air in the sail was tremendous," Scott Eagers said. "It was awesome seeing the whole beach react. Everybody didn't even think, they just ran down, grabbed the rope, and started hauling those girls down."
"There were some people out in the water holding on to the rope, and then by that time a bunch of us had got on the shore and started pulling it in, too. And we just started pulling 'em in," Randy Miller said.
Thank God for all those people," Chelsea said. "Thank God for them."
Don Waddell had arrived in town for a Thrashers game against the Tampa Bay Lightning last Saturday.
"We are so lucky, so very lucky that people responded and helped," he said of the rescue.
He said employees of the parasail company did not apologize to the family or explain what happened. A woman who answered the telephone at the business said no one was available to talk, but instructors would probably issue a statement later in the week.
The girls, who are both from Atlanta, vow never to parasail again.