In the morning, the four engine airplane departed Alameda NAS, California, for Wilmington, with an intermediate stop in Indianapolis, carrying cargo on behalf of the US Air Force. While cruising over Colorado, the crew modified his route to avoid a thunderstorm area. Few minutes later, while cruising in better weather conditions, the left wing detached by section 162. The aircraft rolled and yawed sharply and after the left wing completely failed, the right wing failed outboard of the n°4 engine. Out of control, the airplane entered a dive and crashed in an open field. All four crew members were killed.
Probable cause (official findings): The undiscovered, preexisting fatigue cracks, which reduced the strength of the left wing to the degree that it failed as a result of positive aerodynamic loads created by moderate turbulence.