Originally Posted by
jimf671
No room left under the rug with this one since the same thing happened with the pilots and the aircraft behaviour. They were presented with what we now know was evidence of impending failure but in the circumstances they were able to assure themselves that the effect was typical of local air conditions.
Jim: all points taken and accepted. Our hindsight is 20-20, but your point on the human factors piece of the pilots diagnosing the yaw/controllability excursion as something else (since there were not other cockpit indications?) fits my general idea.
Regarding that thing ...
"huh, what's with the controls here, what just happened"
I am having a flashback to a 1982 SH-2F accident. A control position/controllability issue arose and the pilots landed. They tried to figure out what was wrong and reset the boost/flight control system, thinking it to be an electronic anomaly. (Occasional hiccups in the flight control system, electronic sub systems, wasn't that uncommon). They decided to take it back to the hangar to get it looked at.
As it happened, when they lifted up to air taxi there, the helicopter came apart. (A guy in my squadron saw it happen; he was at the other end of the airfield awaiting clearance to take off and happened to be facing so he had a front row seat).
It was later discovered that the azimuth (for an H-2 that's basically the swashplate) had come untorqued and when the load to pick up hit it, it separated. A novel failure, to say the least, but a nasty one. As you can imagine, parts went everywhere. One fatality, the crewman, trapped in the burning wreckage because the radar came off the rack and pinned him.
Some changes to various flight control malfunction/emergency procedures was made, and the Navy/OEM got together to make some improvements to the azimuth/swashplate to prevent that happening again. From memory, I don't recall that particular issue ever came up again.