“We’re treating it as a non-issue,” said Olson Anderson, the airline’s vice president of flight operations.
According to Anderson, the pilot of Flight 792 said the plane’s Traffic Alert and Collision Avoidance System, or TCAS, did not issue a warning. TCAS analyzes the projected flight path of approaching aircraft to alert pilots to potential collisions.
Perhaps the lack of TCAS alert would be due to them being inhibited at low altitudes?
TCAS RAs are inhibited below 1000ft and switches automatically to TA only, and TA voice alerts are inhibited below 500ft.