Estado:	Final
Fecha:	29 JUN 1972
Hora:	10:37
Tipo:	de Havilland Canada DHC-6 Twin Otter 100
Operador:	Air Wisconsin
Registración:	N4043B
Numéro de série:	13
Año de Construcción:	1966
Horas Totales de la Célula:	15664
Motores:	2 Pratt & Whitney Canada PT6A-20
Tripulación:	Fatalidades: 2 / Ocupantes: 2
Pasajeros:	Fatalidades: 6 / Ocupantes: 6
Total:	Fatalidades: 8 / Ocupantes: 8
Víctimas de la colisión:	Fatalidades: 5
Daños en la Aeronave:	Anulado
Consecuencias:	Written off (damaged beyond repair)
Ubicación:	ca. 8 km S of Appleton, WI (Estados Unidos de América)
Fase:	Aproximación (APR)
Naturaleza:	Vuelo Doméstico Programado
Aeropuerto de Salida:	Sheboygan Memorial Airport, WI (SBM), Estados Unidos de América
Aeropuerto de Llegada:	Appleton-Outagamie County Airport, WI (ATW), Estados Unidos de América
Número de Vuelo:	671

Descripción:
North Central Flight 290, a Convair CV-580 departed Green Bay (GRB) at 10:30 for a flight to Oshkosh (OSH), Milwaukee (MKE) and Chicago. The aircraft climbed to 2,500 feet and proceeded on an approximate course to Oshkosh. At 10:35 the flight made its initial contact with Oshkosh tower stating, "...we're about, seven northeast, two thousand five hundred, VFR." The crew were cleared for a runway 27 landing at 10:36. At that same time, an Air Wisconsin Twin Otter turboprop plane was on its way from Sheboygan (SBM) to Appleton (ATW) at the same altitude. An in-flight collision occurred at 10:36:47 over Lake Winnebago, at an altitude of approximately 2,500 feet. Explosion and fire followed the and both aircraft fell into Lake Winnebago. The accident occurred in hazy sunlight below a scattered cloud layer.

PROBABLE CAUSE: "The failure of both flight crews to detect visually the other aircraft in sufficient time to initiate evasive action. the Board is unable to determine why each crew failed to see and avoid the other aircraft; however, the Board believes that the ability of both crews to detect the other aircraft in time to avoid a collision was reduced because of the atmospheric conditions and human visual limitations."

Fuentes:
» NTSB-AAR-73-9