Northwest Orient Airlines Flight 421

[3] The aircraft departed Midway Airport[4] at 3:50 pm, CST, carrying 33 passengers, 4 crewmembers, 800 US gallons (3,000 L; 670 imp gal) of fuel, and 1,038 pounds (471 kg) of baggage.[1][2] Weather reports received prior to departure indicated relatively clear conditions with a few scattered rain showers en route in the vicinity of La Crosse, Wisconsin and Rochester, Minnesota.At 4:55 pm, the aircraft reported its position over La Crosse, Wisconsin, about 125 miles (201 km) southeast of Minneapolis.[5] In its August 30, 1948, edition, The New York Times reported: The crash occurred on Sutters Ridge, between Winona and Fountain City, Wis., on the Wisconsin side of the Mississippi.The sides of the ravine were so steep, rescuers formed a human chain to carry the passengers' remains 150 feet (50 m) up the rocky crevice.[1] The CAB report concluded: [D]ue to the high local stress concentrations of this particular design of the attachment fitting, fatigue cracks had developed in the attachment fitting which so weakened the structure as to cause failure of the complete outer wing panel under the stress of the severe turbulence encountered in the thunderstorm.Glenn Martin, president of the aircraft manufacturing corporation, dismissed the lawsuit as a mere formality, a bit of meaningless legal maneuvering to appease disagreeing insurance companies.[1] It was Northwest Orient Airlines's worst air disaster at the time, and the first accident in over a billion miles of flight.
An illustration of the wing root assembly from the Civil Aeronautics Board accident report
Structural failureFountain City, WisconsinWinona, MinnesotaMartin 2-0-2Northwest Orient AirlinesRegistrationChicago Midway AirportChicago, IllinoisMinneapolis-St. Paul International AirportMinnesotaMinneapolis, MinnesotaCivil Aeronautics BoardfatigueLa Crosse, WisconsinRochester, Minnesotaroll cloudbarrel rollMississippi Riverfuselagetail assemblystabilizerGlenn L. Martin CompanyList of accidents and incidents involving airliners in the United StatesAviation Safety NetworkWayback MachineUS Department of TransportationStar TribuneNorthwest AirlinesFlight 2Flight 1Flight 5Flight 4422Flight 307Flight 2501Flight 710Flight 1-11Flight 706Flight 705Flight 293Flight 305Flight 6231Flight 255Flights 1482 and Flight 299Flight 85Flight 327Flight 188Flight 253Lovettsville air disasterEastern Air Lines Flight 21Northwest Airlines Flight 5TWA Flight 3American Airlines Flight 28Pan Am Flight 1104American Airlines Flight 63 (Flagship Ohio)American Airlines Flight 63 (Flagship Missouri)Tamaqua, PA crashAmerican Airlines Flight 2TWA Flight 277South Portland A-26 Invader crashAmerican Airlines Flight 6001Eastern Air Lines Flight 45National Airlines Flight 16Pennsylvania Central Airlines Flight 105Mount Tom B-17 crashTWA Flight 513Columbus mid-air collisionUnited Air Lines Flight 521Eastern Air Lines Flight 605Pennsylvania Central Airlines Flight 410United Air Lines Flight 608Pan Am Flight 923Mantell UFO incidentLos Gatos DC-3 crashDelta Air Lines Flight 705Northwest Orient Airlines Flight 4422United Air Lines Flight 624Lake Mead Boeing B-29 crashGeorgia USAF Boeing B-29 crashAirborne Transport DC-3 disappearanceStrato-Freight Curtiss C-46A crashStandard Air Lines Flight 897REastern Air Lines Flight 537American Airlines Flight 157AlaskaHawaiiAviation accidents and incidentsBSAA Star Tiger disappearanceHeathrow disasterNorthwest Airlines Flight 4422Gatow air disasterPan Am Flight 1-10British European Airways Flight S200PBodaybo Li-2 crashSabena Douglas DC-4 crashCebu Philippine Air Lines DC-3 crashUnited Airlines Flight 624Keerbergen Fiat G.212 airplane crashNorthwood mid-air collisionPBY Catalina Miss MacaoLake Mead B-29 crashAir France Flight 072Sabena Douglas C-47 crashAustralian National Airways DC-3 crashRoyal Air Force Avro Lancaster crashBukken Bruse disasterWaycross B-29 crashAeroflot Ilyushin Il-12 crashKLM Constellation disasterBeechcraft Model 18 disappearance