Now, the U.S. Army Corps of Engineers will focus on retrieving the mangled helicopter, a crucial component in federal authorities' probe as they look to confirm data related to its altitude at the time of the collision,

A key safety system was turned off in a US army helicopter when it crashed into an American Airlines flight last week, killing 67 people.

In an update on Tuesday, officials say that transcriptions for both aircrafts cockpit voice recordings are ongoing.