Investigation into DC plane and helicopter collision looking at potential mistakes in ‘no margin for error’ situation

As recovery crews endure cold water and miserable rain Friday to attempt to pull more wreckage of American Airlines Flight 5342 and an Army Black Hawk helicopter from the Potomac River, investigators are intensifying their search for the collision’s cause – with initial concerns already raised about the path of at least one of the aircraft.

As recovery crews endure cold water and miserable rain Friday to attempt to pull more wreckage of American Airlines Flight 5342 and an Army Black Hawk helicopter from the Potomac River, investigators are intensifying their search for the collision’s cause – with initial concerns already raised about the path of at least one of the aircraft. The helicopter was on a training mission when it collided Wednesday night with a commercial plane that was on approach to land at Washington’s Reagan National Airport – a collision that killed all 64 aboard the plane and the three soldiers in the helicopter, officials have said. The National Transportation Safety Board, which is investigating the cause, will take about 30 days to release a preliminary report, and a final report, which will determine a probable cause, will take much longer, it said. Still, details about the collision’s circumstances and potential avenues for the investigation are emerging. Here’s what we know: The Black Hawk had been using specialized corridors utilized by law enforcement, medevac, military, and government helicopters in the Washington area. FAA charts show helicopters in the corridor where the Black Hawk was at the time of the collision – east of the airport and perpendicular to the approach to one of the airport’s runways – must be at or below 200 feet above sea level. But flight tracking data from the moments before Wednesday’s fatal midair collision appear to show the Black Hawk flying 100 feet above its allowed altitude, and veering off the prescribed route along the Potomac River’s east side. The helicopter’s turns would have put the Black Hawk closer to the airport than the standard route.