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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
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