Originally Posted by
Mick Cullen
Does anyone have any first or second hand knowledge of a jammed control event? What happened and how was the helicopter recovered?
Then there were the BO105 hydraulic pack issues. Here's two. The mis-matched SYS1/SYS2 switch-over links and the infamous "SYS1 spool valve jam due to FOD in the fluid". Both caused a hydraulic lock of the flight controls. The 1st aircraft was performing a "block test" when it jammed. Fortunately the aircraft was on the ground. Had it been flying and a microswitch had caused the switchover, who knows what would have happened. On the 2nd jam, the aircraft returned fine after a lawn dart dive toward the ground, but the look on the their faces was much more "interesting" than in the 1st case. I believe, the Hyd Pack switch-over inspection came from this incident as well, but could be mistaken.