2006 Mercy Air Bell 412 crash

The 2006 Mercy Air helicopter accident occurred on December 10, 2006, about 1755 Pacific Standard Time, when a Bell 412SP helicopter, call sign "Mercy Air 2," impacted mountainous terrain near Hesperia, California and the Cajon Pass. The commercial helicopter pilot and two medical crew members were killed and the helicopter was destroyed by impact forces and a postcrash fire.
On July 30, 2008, the National Transportation Safety Board released its probable cause report on the accident. According to the NTSB, the probable cause of the crash was "the pilot's inadvertent encounter with instrument meteorological conditions and subsequent failure to maintain terrain clearance." The dark night conditions, fog, and mountainous terrain were ruled to be contributing factors.

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