Portal:Civil Aeronautics Board

“ Therefore, it can be postulated that an order to continue the flight by visual means during the final portion of the approach a rapid descent became necessary to remain below the clouds and to keep the ground and/or airport beacon in sight. If both pilots were concentrating on conditions outside the cockpit, and the altimeters were unmonitored, it is possible that the descent was continued until contact with the ground was unavoidable. Power was added by the crew when it was realized they were at a dangerously low altitude. However, the power application was too late to prevent ground impact. ”

“ Finally, the airspeed at impact, which was determined to have been approximately 134 knots, should have been more than sufficient to counteract the effects of severe airframe icing if such a situation were present.
The effects of severe turbulence combined with heavy airframe ice would, of course, constitute an additional control problem. A situation of this type would compound existing controllability problems normally associated with severe airframe ice but should not have rendered the aircraft incapable of controlled flight. ”

“ Frontier Airlines Flight 32 of March 12, 1964, crashed and burned during an instrument approach to the Miles City Airport, Miles City, Montana, about 2050 m.s.t. All five occupants, three crew members and two passengers were killed, and the aircraft was destroyed. Weather conditions last reported to the flight were the operational minima of ceiling 400 feet and Visibility one mile. ”