Page:CAB Accident Report, Northwest Airlines Flight 1.pdf/11

Rh clouds at 500 feet, visibility 7 miles, light rain; wind east-northeast 19 m.p.h. A special weather observation issued at Miles City at 11:52 indicated that the ceiling was 700 feet, overcast, ragged, light rain, visibility 1½ miles, wind east—northeast 18 m.p.h., temperature 50°, dew point 50, altimeter setting 29.51. At 12:30 p.m., the airway weather report was ceiling 700 feet, overcast, visibility 1½ miles, light rain, wind east—northeast 17 m.p.h.

After the accident, the two wind vanes at the Miles City Airport were calibrated. The wind indicator on Northwest's office was found to have a 7° minus error; the one on the office of the Civil aeronautics Administration was found to be correct. Since the Weather Bureau was reporting the wind direction as east-northeast at the time the landing was attempted, it would appear that the wind, instead of being across, may have been slightly aft of the beam of the landing aircraft. This would have the effect of slightly increasing the ground speed of the aircraft during the landing approach and the length of the landing roll.

Examination of the Wreckage

The cockpit was crushed and many of the instruments were damaged by the impact or destroyed by fire. The left engine ignition switches and the master ignition switch were in the "on" position; however, the right engine ignition switches were "off". Flaps were "up". Control cables at the cockpit end were destroyed by the intense fire in that vicinity. The right undercarriage and tire were extensively damaged by fire. The tire on the left undercarriage was fully inflated and showed nor major damage. One place in the center of the tread was badly abraded in the direction of the normal travel of the wheel. Beyond the abraded mark, the tire had received a blow sufficient to lift the bead from the rim and allow the entry of weeds.