NTSB Investigator Robert Pearce describes the final moments of the Kennedy flight

That rate of the descent is 10 times faster then normal - far faster than what would be a stressful approach for even the most experienced flier, experts say.

Officials from the National Transportation Safety Board (NTSB) have been piecing together evidence from various sources to work out what happened in the final minutes of the flight.

At a briefing on Tuesday, Robert Pearce - who is heading the NTSB investigation - gave the media a detailed breakdown of what the wreckage, verbal testimony and radar data told him about the crash.

He would not speculate on the damage caused by the crash, but said: "I'm sure you can draw a conclusion by the debris we've been bringing in, which is fragmented."

According to Jim Hall, NTSB Chairman, a full analysis of the crash is not expected for between six and nine months.

This is the sequence of events, based on evidence available so far (all times are given in Eastern Standard Time)

• 2038: Federal Aviation Administration clears Kennedy for take-off from Essex County Airport in Caldwell, New Jersey, a few minutes after sunset

• 2045: Plane climbs to 5,600ft, flying east along the southern Connecticut coast

• 2126: After reaching the town of Westerly (Rhode Island), Kennedy steers the plane out over the Atlantic, flying at 2,500ft, navigating visually rather than relying on instruments

• 2140: Plane drops to 2,200ft, having fallen 300ft in 14 minutes; it makes a right turn, climbs briefly, turns again and then begins a rapid descent

• Plane drops a further 300ft in just four seconds

• It drops another 300ft in the next five seconds

• Five seconds later, it plummets another 500ft before plunging into the sea

• Plane is last seen by radar at 1,100ft, 16 miles from its destination airport