What happened
On September 15, 1957, Northeast Airlines Flight 285 was operating a scheduled passenger service through several stops in Massachusetts, including Martha's Vineyard and New Bedford. After experiencing delays due to a missed approach and poor weather earlier in the flight, the aircraft, a Convair 340 (implied by context of era/type, though source only provides weight/specs), departed Martha's Vineyard for New and New Bedford under Instrument Flight Rules.
The flight was operating with a gross weight of 22,443 pounds. While navigating through instrument weather conditions, the crew communicated with various controllers, including Providence approach control. At approximately 20:38, the pilot reported beginning an ILS approach to runway 05 at New Bedford Airport. The tower controller provided weather updates indicating one-mile visibility in fog and southeast winds of 3 knots.
During the final stages of the approach, the aircraft struck trees in a thick wooded area approximately 4,000 feet before reaching the runway threshold. The impact resulted in 12 fatalities (including both pilots) and 12 injuries. The aircraft was destroyed in the crash.
Findings
Investigation into the accident determined that the pilot attempted to execute a visual approach by descending below the prescribed altitude prematurely. Despite weather conditions necessitating a strict adherence to the ILS procedure, the crew descended to an unsafe altitude in an effort to locate the airport visually using directional instruments. The descent was not corrected before the aircraft struck the trees, which were located roughly 189 feet below the intended glide path centerline.