(CNN) -- Six people were injured Sunday afternoon when a US Airways flight hit severe turbulence shortly after taking off from Philadelphia International Airport, an airline spokesman said.
Five people, including two flight attendants, were taken to hospitals for treatment after the plane returned to Philadelphia, said spokesman Bill McGlashen. The sixth didn't need hospitalization.
There were 265 people on board, including a crew of 10, when the Airbus A330 hit turbulence at about 17,000 feet over Delaware.
"All of a sudden, there was ... a drop like you're going down the bottom of a roller coaster," Jake Levin told CNN affiliate WKMG after the flight arrived about 5 hours late in Orlando.
"You saw ... shoes and apples and all kinds of things (flying in the air). It was so quick," he said. "They weren't sure if we were dropping for good or what was happening."
It was a terrifying experience for his girlfriend Victoria Raines.
"I though we were going down," she said. "I really did."
Flight 735 was flying from Philadelphia to Orlando at the time of the incident. There had been some reports of light turbulence in the area, but nothing as severe as what the plane ran into.
The Federal Aviation Administration will investigate.
In a separate incident, the wing of a WestJet 737 clipped the horizontal stabilizer of a JetBlue plane while on the ground at Orlando International Airport. The horizontal stabilizer is the back set of wings.
The WestJet flight was pushing back from the gate when the incident happened, according to the FAA.
CNN's Joe Sutton and Dave Alsup contributed to this report.