And for more on the many questions surrounding this accident, we turn now to our own aviation correspondent, Miles O'Brien.

So Miles, officials said that initial information showed nothing unusual about the moments leading up to this mid-air collision.

It was a clear night. Both aircraft were in their standard flight paths.

You're a pilot. What questions does all of this raise for you? What was happening in the cockpit of that Black Hawk helicopter? You are

correct, Jeff. Both of them were on the horizontal path that was prescribed. The airliner was making that left-hand turn and lining up for

runway 3-3, right where it should have been at the altitude it should have been. The helicopter

was on a helicopter corridor directly beneath that flight path by only about 200 feet difference on a good day.

In this case, however, they were at the same altitude at the same spot.

And so the question is, why was that Black Hawk helicopter not where it should have been?

Air traffic control did radio them and tell them there was traffic to look out for.

They acknowledged that they saw it. And the important point here that everybody should understand

is that all those helicopters, which buzz up and down the river at 200 feet thereabouts, are flying

under visual flight rules, meaning it is see and avoid.

The pilot looks out the window and is responsible for avoiding a collision.

It is not under direct control of air traffic control.

In this case, air traffic control gave a warning.

They acknowledged their warning.

Then almost immediately there was a collision.

Well, a question about that, because as you say, both the passenger jet and the military

helicopter were under the control of air traffic control at Reagan National.

The New York Times is reporting that an internal FAA report suggests that the controller

on duty last night was effectively doing the job of two people,

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