Friday, August 13, 2010

West bound again

Once again, we were singing that Willie Nelson song, On the road again. All packed and ready to head west.  Unfortunately, just before leaving,  I received word, that Jerry Getz, had an accident while flying a helicopter on one of their contract pipeline patrols. His passenger, a good friend, Mac Minor was killed and Jerry had near fatal injuries and was in critical condition.  The cause of the accident was not know at the time, but early reports, possibly, that before they crashed, he experience an engine overspeed and a sudden loss of rotor RPM.  Jerry Getz had flown in two wars both in Korea and Vietnam and was one of the few successful operators to fly the Cessna Skyhook helicopter for a couple of years. Probably one of the best helicopter pilots in the country.  A pioneer in helicopter aviation and was extremely safety conscious.  The Hughes 269A had a very low inertia rotor system which meant it did not have a lot of energy in a non powered state.  If the engine fails or if for some reason power is not being transferred to the main rotor shaft that turns the rotor, rotor RPM decays very quickly.  In normal autorotation, the helicopter will descend at a very high rate of descent.  When operating at  low altitudes, which would be typical for this type of flight activity, this does not give you much time to take any kind of emergency action to land the helicopter safely.  Also, when you do all the right things, then it is necessary for you to have a suitable place to land.  It does not have to be a large space, but a reasonable level, hard surface, would be preferred.
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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