In the late 1960s , the United States Army began forming requirements for a helicopter to replace the UH - 1 Iroquois .
In the late 1960s , the United States Army designated the program as the Utility Tactical Transport Aircraft System ( UTTAS ) .
In the late 1960s , the United States Army began forming requirements for a helicopter to replace the UH - 1 Iroquois , and designated the program as the Utility Tactical Transport Aircraft System ( UTTAS ) .