On 15 December 1989, a Boeing 747-400 positioning for a planned en-route stop at Anchorage with crew awareness of a significant volcanic eruption in progress some 150 nm upwind entered volcanic ash during descent north northeast of the airport. When an attempt to climb out of the ash using full thrust was made, all engines failed. After repeated and eventually successful engine restart attempts as a 13,000 feet loss of altitude occurred, the fight was completed. The Report of the comprehensive NTSB Investigation remains unpublished with only a brief factual report containing neither Safety Recommendations nor Safety Actions issued.