I heard of John Denver's case and read some reports on the matter. As I recall he picked up the plane at the Seller's airport, judged he had sufficient fuel to make it to his home airport.  He was flying over the Pacific Ocean along the coastline; ran out of fuel.  The fuel selector switch was behind at 8:00 O'clock high.  He reached over with his right hand to turn it to the other tank and pushed on the right pedal and put the plane into a spiral dive into the ocean.  That is what I recall the report said. Sounds like pilot error to me.  the valvve was in the wrong location but then John Denver knew that or should have known that when he bought it. 

 

I surmized that his long exprience in flying could label him as a very experienced pilot. That would go agains them in court.

 

I don't see how Denver's family an get any damages out of a Pilot error situation to me but the Seller's still hve to defend and that is costly. Especially against deep pocket Plaintiffs.

The relatives did not sue the builder.  Extracted from a 2000 article:

 

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-- The relatives of singer John Denver, who died when his home-built plane plunged into Monterey Bay three years ago, have settled their lawsuit against the companies that manufactured and sold a fuel valve for Denver's doomed aircraft.

The settlement amount was not disclosed, and there was no admission of guilt by Gould Electronics Inc. and Aircraft Spruce & Specialty Co., which were named in the suit.

Denver's family had claimed that a faulty valve caused the do-it-yourself Long E-Z airplane to fail off the coast of California on October 12, 1997.

Federal investigators had concluded that Denver took off with too little fuel in one tank, had trouble switching to his backup tank and accidentally sent his plane into a roll as his attention was diverted.

The suit was filed in October 1998 by Denver's children Jesse Belle Denver, Zachary and Anna Kate Deutschendorf and his mother Erma Deutschendorf.

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