Douglas DC-3 accident at Seattle, Washington, 2 Jan 1949

Accident narrative

On January 2, 1949, a Douglas DC-3 operated by Seattle Air Charter crashed and burned following an attempted takeoff from Boeing Field in Seattle, Washington. The flight was chartered to transport a group of Yale University students returning to school in New Haven, Connecticut. Eleven of the 27 passengers and all three crew members received fatal injuries, and the aircraft was destroyed.

### The flight

Departure was originally planned for 1800 but was delayed until a crew was organized at approximately 2100. The crew consisted of pilot G. W. Chavers, who had approximately 6,000 hours of flight time; copilot K. A. Love, with approximately 3,000 hours; and William F. Leland, the sole owner of the irregular air carrier, acting as the third crew member.

During the afternoon, snow had fallen on the parked, uncovered aircraft. As the temperature fell below freezing, the melted snow froze into a rough covering of ice and slush. At approximately 1800, an attempt was made to clear the aircraft using a rope, followed by a high-pressure water hose. This washed away loose snow but left a coating of clear ice on the under surfaces of the wings. As the temperature and dew point equalized at 29 degrees, frost began to form on the iced surfaces.

Emmett G. Flood, a pilot originally obtained for the flight, examined the airplane at 1930 and refused to fly because of the ice. He later stated that he notified a Civil Aeronautics Administration safety agent of the aircraft's condition at 2045; the agent received the message at 2150 and was conferring with a superior when the accident occurred.

Shortly after Flood left the field, Leland, Chavers, and a mechanic made a third attempt to de-ice the aircraft using an alcohol solution on the wings and tail. The mechanic testified that all ice was removed, but he did not examine or attempt to clear the under surfaces of the wings. At 2115, Chavers asked another pilot, John Vineyard, about the ice. Vineyard advised him to obtain plenty of airspeed before taking off. Vineyard later stated that when he examined the airplane just before takeoff, he found a layer of clear ice on the underside of both wings, patches of rime and clear ice on the top of the left wing, and heavy frost forming rapidly.

Investigators later calculated that the aircraft was 1,501 pounds over its maximum allowable takeoff weight of 25,346 pounds, noting that passenger baggage had never been weighed by the company.

### The takeoff

The flight taxied to Runway 13 at 2138 and held because ground fog restricted visibility below the one-mile minimum required for the non-scheduled carrier. The tower reported visibility at 1/2 variable to 1/4 mile. When the flight asked for their minimums and was told one mile, the crew responded, "If we take off we will be in violation, won't we?" The tower answered, "Yes."

After the flight held for ten minutes, the tower noted a break in the weather and cleared the aircraft into position. At 2201, the crew stated they could see the green range lights located 5,700 feet down the 7,300-foot runway and were going to take off. The tower cleared them for takeoff at 2204, reporting visibility at one-fourth of a mile in fog.

The takeoff roll appeared normal for approximately 1,000 feet before the airplane began to swerve left. It became airborne 1,800 feet down the runway on a heading 35 degrees left of the runway. Shortly after leaving the runway, the left wing dropped, dragging its tip on the ground for 117 feet. The aircraft remained airborne for approximately 750 feet before contacting the ground tail wheel first. Power to the engines was cut, and the aircraft skidded 700 feet into a revetment hangar, where it was immediately enveloped in flames.

### What the investigation found

The impact crushed the nose of the aircraft and telescoped it into the fuselage. Fire destroyed the forward section. Investigators found the landing gear down, flaps up, and trim tabs neutral. Examination of the wreckage, engines, and propellers revealed no evidence of structural or mechanical failure prior to impact. The propellers were in low pitch, indicating little power was being developed at impact, and the gyro instruments showed the airplane was on a heading between 90 and 95 degrees at the crash.

The Board noted that three other transport aircraft took off from the same runway between 2130 and 2200 in similar visibility without experiencing difficulty. The Board concluded that the tower personnel had adequately discharged their duties by advising the flight of the weather and providing traffic separation, noting that the pilot in command is solely responsible for the safe operation of the aircraft.

The Board found that the formation of ice and frost on the wings would tend to decrease lifting qualities and increase the weight of an airplane that was already over its permissible takeoff weight. While it was possible the pilot lacked sufficient visibility to hold a straight course, the Board noted his instrument training should have allowed him to continue the takeoff by reference to instruments. Accordingly, the Board concluded the most logical explanation was that the airplane failed to become normally airborne because of the ice and frost known to exist on the wings.

### Probable cause

The Board determined that the probable cause of this accident was "the attempt to take off in an airplane which had formations of ice and frost on the surfaces of the wings."