Unavoidable Turbulence Rocked KC-135:

Air Mobility Command accident investigators have concluded that a May 15, 2005, mishap in which a Wisconsin Air National Guard KC-135R suddenly dropped 400 feet while flying at 37,000 feet over the Caribbean, was caused by “unforeseen, unforecasted, and unavoidable severe clear air turbulence.” The 128th Air Refueling Wing tanker was transporting members of the Virgin Islands Army National Guard from NAS Jacksonville, Fla., to the Virgin Islands. AMC noted that two passengers were seriously injured and other passengers and some crew members sustained minor injuries.