On July 19, 1949, an Air Transport Associates Curtis C-46F Commando, carrying 28 passengers and four crew members, has an engine failure upon takeoff from Seattle-Boeing International Airport. The aircraft crashes into Georgetown, a residential area south of Seattle, killing two passengers aboard the aircraft and five men in a rooming house. Seven houses are either damaged or destroyed and 39 people, including six firefighters, are injured in the mishap. An investigation by the Civil Aeronautics Board will determine that the disaster was caused by pilot error and the improper use of low-octane aviation fuel.
The Curtis C-46 Commando was the largest and heaviest twin-engine transport aircraft used by the U. S. military during World War II. Originally developed in 1937 as a 36-seat commercial airliner (Curtis CW-20), it was used to haul cargo and personnel and for towing gliders. The transport was 74 feet, 4 inches in length with a 108-foot wingspan and powered by two 2,000 hp, Pratt & Whitney R-2800-75 Double Wasp, 18-cylinder, radial engines. At a cruising speed of 173 mph, the C-46 had a range of 3,150 miles and could accommodate up to 36 passengers and a crew of four. Although the plane had a service ceiling of 24,500 feet, it was restricted to flying at lower altitudes when carrying passengers because the cabin was unpressurized. Curtis-Wright produced a total of 3,140 Commandos between 1940 and 1946 when production ended. Many of the surplused military C-46s were purchased at auction for a nominal price by small commercial air carriers and used to transport both passengers and cargo on both scheduled and non-scheduled routes.
On Tuesday, July 19, 1949, Curtis C-46F Commando, registration No. N5075N, operated by Air Transport Associates, Inc. (ATA) prepared for takeoff from Seattle-Boeing International Airport (now King County International Airport). The crew of the aircraft was Captain Merele Edgerton, age 26; First Officer Anthony Gjessing, 35; Flight Attendant Dorothy M. Heacock (1920-2008), 29, and James M. Adams, 25, reserve pilot. The nonscheduled flight was en route to O'Hare International Airport, Chicago, with 28 passengers on board.
Disaster on Takeoff
The C-46 taxied to the south end of Runway 31 and at 8:58 p.m. started to take off. The plane rolled down the 7,500-foot runway for 3,500 feet and then became airborne. During the takeoff, both engines seemed to be having difficulty attaining full power and the left engine began to sputter and backfire. At an altitude of approximately 20 feet, Captain Edgerton retarded the throttles and the ship touched down on the runway. He didn't believe that enough runway remained to safely stop, however, and he advanced the throttles. After the brief touchdown, the C-46 became airborne again and Edgerton retracted the landing gear to reduce drag. The ship passed over the north end of the runway at an altitude of approximately 50 feet, not high enough to clear the power poles and high-tension lines down S Albro Place, just north of the airport.
The doomed plane clipped a 56-foot power pole, tearing off six feet of the right horizontal stabilizer and elevator, hit two more power poles on S Bailey Street and struck a three-story rooming house, located at 961 S Harney Street in Georgetown, demolishing the top story. The plane continued across Harney Street, struck a two-story brick residence located at 954 S Harney Street, and then burst into flames. Five nearby houses were extensively damaged in the crash landing.
The aircraft severed numerous high tension lines which then started several small fires in the neighborhood. The impact ruptured the ship's main fuel tanks, saturating the ground with fuel, and within minutes the site burst into flames. Both the nose and tail sections had separated from the fuselage, allowing the crew and passengers to evacuate before fire enveloped the passenger cabin.
The Boeing Field fire station was located 4,000 feet from the north end of Runway 13. As the C-46 passed the station, the firefighters on duty heard the plane was having engine trouble and headed for their crash trucks. The control tower saw the plane go down and sounded the crash alarm. The first responders arrived at the scene within minutes. Their efforts were quickly augmented by fire and rescue teams and equipment from the Seattle-Tacoma International Airport and the Seattle Fire Department. The gasoline fire was promptly extinguished with foam and the survivors cared for by neighbors until emergency medical help arrived. Soon afterward, ambulances, volunteer firefighters, police, sheriff's deputies, and state patrol officers arrived in the neighborhood en masse. All the survivors were transported to Harborview Hospital in Seattle for medical attention.
The final death toll was seven; two aircraft passengers and five residents of the Harney Street rooming house. King County Coroner John P. Brill, Jr. (1909-1971) had the bodies transported to the King County Morgue at Harborview for positive identification and disposition. Four crew members and three passengers were hospitalized with burns and fractures. Fifteen passengers were treated for minor injuries and released. Eight passengers survived the mishap without injuries. Seven residents of damaged Georgetown homes were hospitalized and one was treated for minor injuries and released. Four firefighters suffered burns in a belated explosion of one of the plane's auxiliary fuel tanks, and two were treated for minor injuries. Considering the devastation, it was remarkable there were so few casualties.
Investigation and Findings
Over the next few days, Civil Aviation Administration (CAA) and Civil Aeronautics Board (CAB) investigators had the wreckage removed to a hangar at Boeing Field for a detailed examination. Fire had destroyed major portions of the aircraft but an inspection of the remaining pieces and parts disclosed no evidence of structural failure prior to impact. Teardown inspections of the two power plants revealed that low-octane gasoline had caused the left engine to misfire and lose power during the takeoff and climb from the airport.
On August 4, 1949, the Civil Aeronautics Board (CAB) opened an official investigation into the ATA crash at Boeing Field. The two-day hearing was held at the U.S. Courthouse in Seattle, during which a panel of five CAB officials elicited testimony from some 30 witnesses into the accident. During the hearing, it was determined that Amos E. Heacock (1914-2004), a passenger as well as the president of ATA airline, was largely responsible for saving most of those aboard the flight. After the crash he evacuated passengers from the cabin, freed the three pilots, who were entangled in cockpit wreckage, and carried his wife, Dorothy, the flight attendant, to safety.
The official CAB Accident Investigation Report, dated August 30, 1950, concluded:"The Board determines that the probable cause of this accident was the indecision of the pilot in continuing a takeoff after loss of power in the left engine, which was probably caused by the use of 91 octane fuel, necessitating the operation of the aircraft's engines in excess of the approved operating limitations" ("Civil Aeronautics Board Accident Investigation Report: Air Transport Associates, Inc., Curtis C-46F, N5075N, Seattle, Washington, July 19, 1949," Civil Aeronautics Board, File No. 1-0056).
Laurence J. Furio, age 19, Chicago
Frank Catolica, age 19, Kalamazoo, Michigan
Peter G. Chumos, age 66
Frank L. Morgan, age 60
Ralph Parker, age 60
Olavi N. Niemi, age 45
Edward Brightcamp, age 71