The version of Double Wasp fitted to early models proved extremely unreliable with many in-flight failures.
The company also stated that investigation into the crash of the prototype ruled out in-flight failures or other problems with the aircraft.
An in-flight failure of a pressure vessel could even result in the loss of the orbiter and its crew.
Brown had been warned to treat the rudder with suspicion due to a number of in-flight failures.
A bird strike or, according to solicitors working on the incident, 'some other form of in-flight catastrophic failure' were also plausible explanations for the crash.
Pre-jet commercial aircraft were designed with as many as 4 engines in part because of concerns over in-flight failures.
All of the extremities of the aircraft were accounted for, and no evidence of in-flight structural failure, fire, or explosion was found.
Like the F-105B, the F-105D's early career was plagued with maintenance problems and in-flight failures.
It was also invoked after the next critical in-flight failure, which occurred on the Apollo 13 lunar mission in April 1970.
The V-1 flew for another three years before suffering an in-flight structural failure and destruction.