NEW YORK • The helicopter lifted off in a damp fog and raced down the East River. But within minutes, the pilot was trying to return to the heliport he had just left.
The pilot, an experienced flier named Timothy McCormack, told the heliport he could not find his way. "McCormack then stated that he did not know where he was," a law enforcement official said on Tuesday.
That was Mr McCormack's last communication before he crashed and died on the roof of a 51-storey office tower in the middle of Manhattan on Monday afternoon, said the official.
Now investigators will try to figure out why Mr McCormack went astray in the 11 minutes after he took off, bound for an airport in Linden, New Jersey, where he usually parked the helicopter.
A team of investigators from the National Transportation Safety Board arrived on Monday night to begin piecing together the scary sequence that for a brief moment had New Yorkers fearing another terrorist attack on their city.
Police officials said they quickly ruled out that possibility.
The investigators may not have much to work with. The helicopter, a twin engine Agusta A109E, slammed so hard into the roof of the building, at 787 Seventh Avenue, that the aircraft was almost completely destroyed.
Mr Doug Brazy, an investigator for the safety board, said a post-crash fire "consumed most of the wreckage". After the remains are inspected on the roof of the building, which has been closed since the crash, a salvage company will remove them - possibly down the stairs or in lifts, Mr Brazy said.
He said the helicopter did not have recorders for voice or flight data, but some of its instruments had memory that the investigators hoped to retrieve and analyse.
Speaking at a news conference on Tuesday, Mr Brazy said Mr McCormack flew a passenger from suburban Westchester County to the East Side of Manhattan in about 15 minutes on Monday morning.
He said the passenger reported that nothing seemed unusual about that flight.
Mr Brazy said Mr McCormack might have attempted to make distress calls near the end of the flight, but he could not confirm that any had been received. He said Mr McCormack was tracking the weather during the nearly two hours he spent at the heliport, but did not know what influenced his decision to leave the heliport.
"Should the helicopter have been flying? I don't know yet," Mr Brazy said.
According to the Federal Aviation Administration, Mr McCormack was not rated to fly by instruments only - which is a requirement for low-visibility conditions.
Mr McCormack needed no clearance to fly the standard route from the heliport to Linden, Mr Brazy said. But he would have needed permission from air traffic control at La Guardia Airport to cross Manhattan, he added.
People who knew Mr McCormack said he was intimately familiar with the skies over New York and had flown around the city for years, largely without incident. Several years ago, he had calmly landed a helicopter full of passengers after a bird crashed into the windshield, a former employer recalled.
Just two hours before the crash, Mr McCormack had dropped off the passenger, whom the law enforcement official identified as Mr Daniele Bodini, at the city-owned heliport at the east end of 34th Street along the East River.
Mr Bodini, founder and chairman emeritus of American Continental Properties, a real estate company, used the helicopter to commute to the city from a home in Westchester.
Mr McCormack, who also lived upstate, had flown for Mr Bodini's company for five years, a company spokesman said.
Seeing a break in the weather, Mr McCormack lifted off at 1.32pm, the law enforcement official said.
Five minutes later, he was on the radio, saying he was turning around and asking for a landing spot, the official said. His helicopter was spotted swooping up and down over the river.
Mr Brazy said he believed that the erratic flight that was captured on video on Monday was Mr McCormack's helicopter. Instead of landing at the heliport, he had headed into some of the most tightly controlled airspace in the country.
At 1.43pm, a caller who works in an office of the Bank of Tokyo made the first 911 call about the crash, the law enforcement official said.
The caller reported that an aircraft had crashed on top of a building between 51st and 52nd streets. Firefighters raced to the rooftop and extinguished the fire.