WASHINGTON (NEXSTAR) - Airspace congestion and air traffic control staffing was the focus of conversation as federal investigators probe the deadly collision between a commercial plane an Army helicopter earlier this year where 67 people died.

More witnesses came forward drawing attention to Army helicopters. They say training in the highly congested air space near the airport has long been a concern.

This year's deadly midair collision outside of Reagan National Airport is a hard pill to swallow for retired Air Force officer turned helicopter medic Rick Dressler. He spends his days navigating that very airspace but told federal regulators Thursday military choppers training there have him and other pilots on edge.

"We are all very uncomfortable when those two units are operating,” said

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