The Swiss military said on Sept. 6 that preliminary investigations revealed that Swiss air traffic agency, Skyguide, had assigned the Swiss F/A-18 that crashed into mountain on a wrong altitude.
By Konstantin von Wedelstaedt [GFDL 1.2 or GFDL 1.2], via Wikimedia Commons
The minimum safe altitude to fly around the mountain ranges of Susten Pass in central Switzerland is above 14,000ft. Yet, the air traffic control assigned the pilot to fly at 10,000ft.