.jpg) A Northwest Airlines's Martin 2-0-2 | |
| Accident | |
|---|---|
| Date | 29 August 1948 |
| Summary | Structural failure |
| Site | Fountain City, Wisconsin, 4.1 mi (6.6 km) NW of Winona, Minnesota |
| Aircraft | |
| Aircraft type | Martin 2-0-2 |
| Operator | Northwest Airlines |
| Registration | NC93044 |
| Flight origin | Chicago Midway Airport, Chicago, Illinois |
| Destination | Minneapolis-St. Paul International Airport, Minnesota |
| Occupants | 37 |
| Passengers | 33 |
| Crew | 4 |
| Fatalities | 37 |
| Survivors | 0 |
Northwest Airlines Flight 421 was a domestic scheduled passenger flight from Chicago, Illinois to Minneapolis, Minnesota that crashed on 29 August 1948. The Martin 2-0-2 aircraft, operated by Northwest Airlines, suffered structural failure in its left wing and crashed approximately 4.1 miles (6.6 km) northwest of Winona, Minnesota, about 95 miles (153 km) southeast of Minneapolis. A Civil Aeronautics Board investigation determined that the crash was caused by fatigue cracks in the wings of the aircraft, and recommended lower speeds and frequent inspections of all Martin 2-0-2 aircraft. All 33 passengers and 4 crewmembers on board were killed. The crash was the first loss of a Martin 2-0-2, and remains the worst accident involving a Martin 2-0-2.