Originally Posted by
Ethel the Aardvark
biggest problem I have heard of was after maintenance the fuel selector knobs were not installed at the correct positions, there is no master spline and can be fitted in potentially 20 odd positions due to its design, if the control cable tubes are not lubed then the selector drives slip as well throwing it out. hope the new ones are better!
Thread drift from original subject of trims. Some years ago there were several Partenavias at Essendon. I recall trying to turn the fuel selectors to their various positions while teaching a student. They were all unacceptably stiff to operate and sometimes needed two hands. I went across the tarmac and tried the same with the other Partenavias. Same defect. I wrote the defects up in the MR much to the annoyance of one operator. I was told it was a well known characteristic with these aircraft and to accept it.
Later I read a UK accident report where a Partenavia was en-route from the Channel Islands to an airport in southern England when an engine failed. I forget the finer details but the female pilot went to use the cross-feed system but was unable to physically move one of the fuel selectors into the cross-feed position. The aircraft was ditched due inability to cross-feed and some passengers were drowned. The pilot survived to tell the tale. The Brits CAA issued an AD that warned of the danger of Partenavia defective fuel selectors.
I contacted BASIS in Canberra with a copy of the AD and evidence of my own experience with Partenavia fuel cock selectors. BASIS then issued a similar AD to Partenavia owners. In brief it required pilots to write up instances of difficult to move fuel selectors and maintenance organisations to check them on scheduled servicing cycles.
Then one day a Partenavia arrived for a 100 hourly. An LAME mate rang me and said come and have a look at this Partenavia which was undergoing other rectification. He said try to move the fuel selectors. They were jammed completely and had obviously been like that for yonks. In fact the problem was at the other end near the engines - not the selectors themselves. He suggested to his supervisor that DCA airworthiness people would be interested and should be advised as a standard procedure in view of the AD. The supervisor told him to forget that idea as the aircraft owner might get upset and go to somewhere else for future servicing.