I came across this while googling ALPA and airline and safety - does anyone know if it is true? Sorry about the length. It is obviously very anti-union, and I don't care about the politics...I am just wondering if this is in fact a real event described accurately...

http://www.airlinesafety.com/Unions/Sisto.htm

The Chuck Sisto affair: Defending dangerous pilots

In October, 1947, American Airlines Captain Charles Sisto hitched a ride on an AAL DC-4 cockpit jumpseat, from Dallas to Los Angeles. For reasons beyond the comprehension of rational minds, he thought it would be a great joke to engage the controls gust lock, without telling the pilots.
Captain Jack Beck, who was flying that DC-4, began to gradually roll in more and more trim for the elevators, which seemed to be resisting the normal pilot inputs on the control wheel, required to maintain the assigned altitude.
Trimming, to relieve excessive pressure by the pilot on the controls, was accomplished by moving a small tab on the trailing edge of the elevators, which are panels hinged to the aft side of the horizontal stabilizer. When the trim tabs were moved upward, that in turn put downward pressure on the elevators. Downward pressure on the elevators would lift the tail of the airplane, and that in turn would lower the nose of the plane, causing it to descend.
However, with the gust lock on, the elevators did not respond to that input from the trim tabs. The trim tabs moved upward, as the trim control was changed by Captain Beck. That would have normally caused the elevators to move down, but because the controls were locked, they did not. As Captain Beck continued to roll in more and more elevator trim (moving that tab upward), it caused the plane to respond in the opposite manner, to which the pilot was commanding. As long as that gust lock was on, the trim tab being moved upwards would tend to make the plane climb. But with the gust lock off, the same action would tend to make the plane descend.
Additional trimming of that tab, while the gust lock was on, had the effect of winding a spring up tight, ready to suddenly release its pent up energy, whenever the gust lock might be moved back to the unlocked position.

And, that is precisely what happened when Captain Sisto finally decided his prank had gone far enough: He moved the gust lock lever back to the unlocked position, without telling the pilots what he had done.
That DC-4 responded immediately by plunging towards the New Mexico desert floor.
Because neither Captain Beck or Captain Sisto had their seat belts on, they were slammed into the cockpit ceiling with the force of that sudden and unexpected maneuver. Their heads collided with three of the four engine propeller feather buttons. The result was that the plane was spared a full-power dive, which would have undoubtedly led to the loss of the plane and all souls on board.
Had they not lost 75 % of the engine power, as the plane entered the dive towards the desert floor, that plane would probably have come apart before hitting the ground.
Fortunately, Captain Logan (flying the First Officer position) did have his seat belt fastened securely in place. As the plane reached the inverted portion of the unplanned outside loop, only about 400 feet above the desert floor, he rolled it upright with the ailerons and managed to regain control until they could slow below the redline speed and limp to an emergency landing, which saved all 54 lives on board.
"The aircraft was placed under lock and key in a hanger at El Paso until a complete and thorough examination could be made by the Board's investigators. The day following the accident the crew made preliminary statements which indicated that there might have been some difficulty with the automatic pilot, which all three pilots stated had been engaged just prior to the maneuver previously described. For this reason tests were made of the automatic pilot which included its operation in this aircraft in actual flight. No evidence was found of any structural failure or mechanical malfunctioning of the automatic pilot or any other component of the aircraft.
Supplemental statements made by the three pilots on October 15, 1947, indicated that the automatic pilot was not engaged at any time during the flight but that Captain Sisto, sitting on the jump seat, engaged the gust lock while the aircraft was in level flight. Captains Beck and Logan further stated they were not aware of his action at the time. The aircraft started to climb and when rolling the elevator trim tab control nose-down did not return the plane to level flight, Captain Beck turned to Captain Sisto and asked, "Is the automatic pilot on?" Upon receiving a negative reply, he thought of the possibility of the gust lock having become engaged in flight and reached for the trim tab control to neutralize it. Before this could be accomplished, however, Sisto released the gust lock lever, and it being spring loaded permitted the gust lock to return to the unlocked position. The elevator was then free to be moved by the trim tab which had been placed in an extreme upward or airplane nose-down position. The sudden and violent movement of the elevator surfaces to a down position, upon release of the gust lock, caused the aircraft to pitch down violently as previously described."
The passengers and stewardesses (yes, that was the correct nomenclature, in those days......), who did not have their seat belts fastened, were also thrown up against the ceiling. Fortunately, their injuries were only minor.
Of course that ended the pilot career of Captain Chuck Sisto----but only because American Airlines management and the CAB rejected the ludicrous defense of Sisto, by Dave Behncke, the President and founder of the Air Line Pilots Association (ALPA).
Dave Behncke defended Sisto to the bitter end, by arguing that
"This incident could have been averted had the DC-4 been equipped with a properly designed gust lock system."
There you have it in a nutshell, what the original purpose of ALPA----the purpose which the founder of ALPA, Dave Behncke, saw as more important than all other considerations in the airline industry. More important than the safety of the trusting passengers who purchased their tickets with the full confidence and trust that the pilots would operate their plane with the highest of standards. Trusting passengers who believed their pilots had the kind of sound and rational judgment, which could fairly be expected of anyone who even aspired to be an airline pilot.
It was clear, from this and other bizarre behaviors of Dave Behncke, that ALPA was founded by a mental case who was incapable of discerning what was rationally and morally required of any person who would be hired to pilot airliners full of trusting passengers. Behncke only cared about power----the power to deny airline managements the right and ability to get rid of dangerous pilots. ...