The NTSB gave an update Friday on the devastating crash in Washington, D.C., between an American Airlines plane and U.S. Army Black Hawk helicopter.

The US National Transportation Safety Board on Friday gave a much-anticipated update on its investigation into a deadly collision between two aircraft late last month, saying that officials were looking into an inconsistency in the data with regard to the height of the helicopter at the time of the crash.

The crew of a US Army helicopter may have had faulty altitude readings and not heard a key instruction from air-traffic controllers moments before colliding with an American Airlines Group Inc. regional jet near Washington in late January,