Later on, it was thought that the cause of the accident was thought to be a problem with the fixed metal lock for the clutch lever. I had thousands of flight hours in this type of helicopter and never had any problems with this system, but I could see how it could be one of those one in a million conditions.
CLUTCH CONTROL LEVER click to enlarge |
Looking at the picture above, you see a clutch lever that has a small black knob on the end of it. After the engine is started and at the proper time, the pilot pushes this lever forward and down and locks it into the fixed metal tab (Lever Lock) at the forward side of the seat box. This keeps tension on the belt drive system and also drives the main rotor transmission, which in turn, rotates the main drive shaft that is connected to the main rotor. Now picture this. Take your right hand and hold it out with two fingers spread apart and pointing down. Now take your left hand and place the index finger between the two fingers that are spread apart on the right hand. Simply, this is how this system works. Your left hand index finger being the clutch lever, and the two fingers of the right hand being the lever lock. Now their is a tremendous amount of tension on the clutch lever cable which is between the lever and the belt drive system. Now just suppose that when you engaged the lever, that instead of the lever going between your fingers and it was accidental placed to make contact with the bottom of one of your fingers. Then later on, the lever which is not secured, because it is not locked between your fingers. It slips to one side and then the lever snaps back and the tension on the belt drive system is released. This would cause the engine to overspeed and the rotor RPM to decrease rapidly. Later on, an A.D.(Airworthiness Directive) came out to modify this lever lock, so this could never happen again. Sorry to bore you with all the nuts and bolts, but it's sometimes interesting to find out that a very simple thing could cause a very bad accident.
I drove on to Kansas City and visited Jerry Getz at the hospital. His back was broken in three places and he had several ribs broken. He made a full recovery but was permanently grounded due to medical reasons caused by his injuries. I really thought maybe this would change in time, but it didn't. I know Jerry felt bad about Mac, but I can't see that his death was caused by anything he did. Accidents do happen. I did not stay in Kansas City very long as I was on a very tight schedule..........................
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