|
|
Bill,
Thank you for that clarification. When I read Perry's
comments, I was wondering "why?" - because the system I'm
building has the functions: Left, Right, Both, None.
Now I'm not so worried, because each high pressure fuel
pump draws from it's own tank and the only point of inter-
connection is where the lines join at the fuel rail(s).
I borrowed the basis of my setup from Marc and Nadine
Parmalee's COZY:
http://www.marcnadine.com/fuelvalve.html
Dale R.
> From: "BillDube@killacycle.com" <billdube@killacycle.com>
> Date: 2005/05/29 Sun AM 02:03:31 EDT
> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> Subject: [FlyRotary] Re: Paul's Fuel System Error
>
> About a year ago I did a little "Google" research on the John
> Denver fatal crash. The bottom line appeared to be that one tank was empty,
> and the fuel selector was not fully turned to the other tank. (It was in a
> very awkward position to reach, and this may have also caused the pilot to
> auger in while attempting to reach it.) Thus, it was in the equivalent of a
> "both" position. This caused air to be drawn in to the fuel supply line
> from the dry tank. This, in turn, caused the pump to lose its prime and
> stop pumping fuel to the engine.
>
> As Perry mentions in his post, only a gravity feed fuel system can
> have a "both" type fuel selector. Low-wing aircraft that have negative
> pressure in the fuel lines from the tanks must NOT have a "both" position
> on the fuel selector, otherwise the pump (or the sump) will suck air if one
> tank runs dry (or if there is a leak in a fuel line.)
>
> This kind of makes you want to put a pump in each tank.
>
>
>
> At 06:56 PM 5/28/2005, you wrote:
> >Rotary Enthusiasts:
> >
> >I have not had time to keep up with the message traffic on this list in
> >real time. But I did take some time this weekend to search the archives
> >for clues to Paul Conner's accident. I found he made a major mistake in
> >his fuel system. It does not mean this was the cause of the accident, but
> >it's possible. I want to make sure no other Canarders out there do
> >something similar.
> >
> >Attached are two pictures from the Long-EZ plans. You see the fuel system
> >is a low-wing fuel system, like a Piper. Pipers and other low wing
> >aircraft do not use a L-R-BOTH-OFF fuel selector valve, they only use
> >L-R-OFF. Only high wing Cessna's use the L-R-BOTH-OFF system.
> >
> >Here is the link to the message where Paul says he uses a L-R-BOTH and
> >normally runs on BOTH. He says he did that on his previous Long-EZ as
> >well, but that also was an error.
>
> Bill Dube <LED@Killacycle.com>
> http://www.killacycle.com/Lights.htm
|
|