Flight 99 originated in
Nome on Saturday, August 30, 1975, bound for
Savoonga and Gambell. Captain William C. Arant (39), who had 6,607 flying hours prior to the journey, and First Officer Gerald W. Schaefer (28) who had 2,738 flight hours were on board. The flight from Nome to Savoonga was uneventful, and the plane departed Savoonga for Gambell at 1:27 pm
Bering daylight time. As Gambell did not have a
control tower, the Wien agent at Gambell, upon hearing the plane radio its departure from Savoonga, turned on the
non-directional beacon at Gambell to aid the flights crew in navigation.
Fog was prevalent in the Gambell area, and the crew discussed strategies to land at the airport. After several
missed approaches, the plane flew north over the community, and turned east, and then south to make one final pass. The plane passed over Troutman Lake east of Gambell, and turned south, before impacting Sevuokuk Mountain at an elevation of . attempting to put the fire out with hand-held extinguishers. ==Cause==