AURORA, Ill. - A helicopter that crashed while transferring an infant girl between hospitals overnight likely hit a radio tower guy wire with enough force to rip the main rotor blade shaft from the craft while it was still in the air, investigators said yesterday.
The collision showered an apartment complex parking lot nearby with rotor fragments and sent the helicopter into an out-of-control spin that ended in a fiery crash in a field below, killing all four aboard.
"A rotor blade is not designed to travel through anything but air," said National Transportation Safety Board Investigator-in-Charge John Brannen.
Once the rotor struck something else, it ripped apart and scattered debris 100 yards from where the rest of the wreckage landed. "That indicates that the main rotor separated from the aircraft in flight," Brannen said.
The impact killed a 13-month-old girl, Kirstin Blockinger of Leland, Ill., who hospital and air transport officials said was being treated for seizures.
Also killed were the pilot, Dell Waugh, 69, of Carmel, Ind.; a nurse, William Mann, 31, of Chicago; and paramedic Ronald Battiato, 41, of Peotone, Ill.
"You heard a boom and felt an impact. I thought someone had ran into the side of our house," said London Hall, 30, a resident of the apartment complex near where the helicopter crashed just before midnight Wednesday. "I looked out my bedroom window and flames were everywhere."
"You could hear the helicopter really, really loud," said Keith Pudlewski, 33, who was reading a novel in a second-story apartment. "And the next thing you know, you hear 'boom.' "
The crash of the Bell 222 helicopter run by Bolingbrook-based Air Angels Inc. is the third for the company in six years and prompted Children's Memorial Hospital - the flight's destination - to suspend flights from the company yesterday.
Air Angels has flown critical-care flights in Illinois, Indiana and surrounding states for more than 10 years, according to a company statement. The company also grounded its remaining flights, a spokesman said.
Emergency medical officials in Maryland have been re-evaluating medical transport standards in the wake of a helicopter accident that killed four people in Prince George's County last month.
More than 500,000 medical transport flights take place in the United States each year.
The girl killed in the Aurora crash originally was bound for Central DuPage Hospital, but the closer hospital where she had been treated before was full, said Julie Pesch, a spokeswoman for Children's Memorial.
The craft, a sleek Bell 222 helicopter that was a workhorse for medical flights and a star of local aviation shows, was based at Clow Airport in Bolingbrook.
The pilot reported no mechanical problems before takeoff and weather was not an issue below 10,000 feet, officials said.
Brannen said the pilot had last been in communication with the tower at DuPage Airport, where he asked for clearance through the airspace. Waugh was flying about 700 feet above the ground.