CRM grew out of the 1977 Tenerife airport disaster, in which two Boeing 747 aircraft collided on the runway, killing 583 people. A few weeks later, NASA held a workshop on the topic, endorsing this training.[6] In the US, United Airlines was the first airline to launch a comprehensive CRM program, starting in 1981.[7] By the 1990s, CRM had become a global standard.[3]