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and trim figured out on this thing."
Following the first approach the pilot transmitted, "I'm going to try to land on elevator tab instead of autopilot. I get a little better control using power and trim." Out of context this transmission could indicate the pilot had or thought he had pitch control on autopilot. In context with the other transmissions and in consideration of the emergency, it is the Board's judgment that the pilot meant he was discontinuing use of the autopilot and the power and trim combination. It meant he would use manual control for lateral and directional control and power and trim for control in the pitch axis.
Operationally, without normal elevator control, landing the aircraft using power and trim would be a most difficult task. During the approach the pitch control would lack "feel" normally obtained through the yoke. Over-control would be unavoidable because of the jerky and lagging response of the aircraft to power and trim. Further, these difficulties would be increased greatly because the manner of control required increased hand movements and would entail a sudden departure from orthodox procedures. Once the aircraft was on the runway the slightest irregularity in the runway or wind gust could cause it to bounce or "porpoise." Considering all the operational circumstances, to prevent the bounce from becoming a "porpoise" or to damp the "porpoise" using power and trim would be extremely difficult. In view of the foregoing, the Board is of the opinion that there were no operational factors that caused or contributed to the cause of this accident.
Probable Cause
The Board determines that the probable cause of this accident was loss of elevator control because of an improperly secured bolt, a condition which was undetected because of an inadequate inspection.
BY THE CIVIL AERONAUTICS BOARD:
| /s/ | JAMES R. DURFEE |
| Chairman | |
| /s/ | CHAN GURNEY |
| Vice Chairman | |
| /s/ | G. JOSEPH MINETTI |
| Member | |
| /s/ | WHITNEY GILLILLAND |
| Member | |
| /s/ | ALAN S. BOYD |
| Member | |
