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It appears from the evidence that both Captain Bates and First Officer Onsgard were physically qualified and held the proper certificates of competency covering the flight and equipment involved.
Airplane and Equipment
Aircraft NC 21712 was a Douglas, model DC-3A, manufactured by the Douglas Aircraft Corporation of Santa Monica, California, and purchased by Northwest on April 25, 1939. It was powered with two Pratt and Whitney SC3G engines, each rated at 1050 horse power for take-off, and was equipped with Hamilton Standard, constant speed, hydromatic, full-feathering propellers. The hub model of these propellers was 23E50-109 and the blade design was 6153A-18. This model aircraft and its equipment had been approved by the Civil Aeronautics Administration for air carrier operation over routes flown by Northwest with 22 passengers and a crew of 3. The airplane had been certificated for operation with a standard weight of 24,400 pounds and provisional weight of 25,200 pounds[1]. The airplane and its equipment had received the overhauls, periodic inspections and cheeks which are provided for in company practice and approved by the Civil Aeronautics Administration.
History of the Flight
Northwest's Trip 5 of October 29, 1941, originated at the Chicago Municipal Airport, Chicago, Illinois, with Seattle, Washington, as its destination. Intermediate stops were scheduled at Minneapolis, Minnesota; Fargo, North Dakota; Billings, Montana; Butte, Montana and Spokane, Washington. Captain Bates and First Officer Onsgard were assigned to operate the flight from Minneapolis to Billings.
Trip 5 was scheduled to depart Minneapolis at 12 midnight. In planning the flight, Captain Bates and Northwest's Minneapolis dispatcher had available the 10:30 p.m. airway forecast made by the United States Weather Bureau Station at Chicago, which included the area proposed to be traversed by the flight and the terminal forecast for Fargo. The area forecast reported the existence of a cold front which, at the time the forecast was made, had reached Fargo and was moving eastward at approximately right angles to the airway and predicted that the front would advance to near the Duluth, Minneapolis and Des Moines line by 6:30 a.m., October 30. Snow was predicted over northern Minnesota during the period of the forecast with overcasts at about 500 feet in that area and from 600 to 1200 feet in the eastern Dakotas. It was predicted that in the snow areas of northern Minnesota visibility would be from 2 to 5 miles, increasing to over 6 miles to the rear of the cold front. Icing conditions were forecast in clouds in advance of the front in all parts of the area except northern Minnesota and Wisconsin where such conditions were expected above 5000 feet above sea level. The forecast also contained a general statement that there would be "icing in clouds to rear of front", indicating that icing conditions might be expected at any altitude behind the front. No attempt was made to predict the severity of these conditions.
- ↑ The "standard weight" of an airplane is the maximum allowable weight for landing while the "provisional weight" of an airplane is the maximum allowable weight for take-off. When an airplane takes off with a weight in excess of the designated standard weight, the weight of the airplane must be reduced by gasoline consumption, prior to arrival at its next scheduled stop, to the extent necessary to bring it within the standard weight for landing. If sufficient gasoline has not been consumed between the time of take-off and any emergency landing, gasoline can be dumped by the use of tested and approved dump valves in order to reduce the total weight to the approved gross weight for landing.
