NTSB holds hearings to determine why passenger plane and Army helicopter collided in January, killing 67 people

By Alexandra Skores, Pete Muntean, CNN

Washington (CNN) — The first of the National Transportation Safety Board’s three days of investigative hearings is underway to help determine what caused the deadly midair collision on January 29 between an Army helicopter on a training mission and American Airlines flight 5342 landing at Ronald Reagan Washington National Airport.

The NTSB presented for the first time major “discrepancies” in the altitude readouts on board the US Army Blackhawk helicopter that led to the crew believing they were flying lower over the Potomac River than they actually were.

Investigators said Wednesday that, following the crash, they tested three of the same models of Blackhawk helicopters from the same Army unit involved in the collision flying over the river.

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