Page:CAB Accident Report, 1934 Northwest Airlines crash.pdf/2

- 2 - speed and the plane slid off on the right wing and nose, cartwheeling some seventy-five feet and coming to rest in an upright position.

From our investigation and public hearing, it appears that the airplane had just recently been received from the factory and had been put into service without anyone having a definite knowledge of the amount of fuel it consumed per hour of normal flying. This trip was Pilot Ohrbeck's first flight in this particular plane, and he took off on the general assumption that its fuel consumption was about forty-three gallons per hour. Although the fuel gauge readings after 1½ hours of flying (right tank 5/8 full; left tank full) indicated that something wasn't just right when fuel should have been draining from both tanks, the gauge readings after landing at Milwaukee (right tank 5/3 full; left tank 1/2 full) indicated a fuel consumption reasonably close to the general assumption of 43 gal. per hour.

However, an inspection of the fuel system after the accident disclosed that the right tank contained from fifty to sixty gallons of fuel and that the feed lines from this tank were full. The left tank was found to contain about one gallon and the feed lines were dry. Both carburetors contained a few drops of fuel. This indicated an actual fuel consumption of approximately 60 gal. per hour and although his left gauge indicated a tank one-half full, actually the tank was practically empty at time of takeoff from Milwaukee.

It is the opinion of the Accident Board that the probable causes of this accident were

1. Failure of the Supervisory Personnel to definitely determine the actual fuel consumption of a new airplane before placing it in scheduled operation.

2. Failure of the fuel gauge on the left tank to function accurately.

3. Pilot error for failing to attempt to use the right fuel tank after the instrument board warning light had indicated that the tank which he was using was about empty.

Respectfully submitted,