Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Mon, 23 Dec 2002 18:05:14 -0500
Message-ID: <redirect-1933499@logan.com>
Reply-To: "Dan Schaefer" <dfs155@earthlink.net>
From: "Dan Schaefer" <dfs155@earthlink.net>
Subject: Re: LCN2 fuel system
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Bad idea, Angier.

As noted elsewhere, The two wing tanks will not feed evenly (and you won't
have any control over that) and sooner or later, one will empty faster than
the other. When that happens, your pumps can/will preferentially draw air
from the empty tank - not a good thing! I'm not sure but I don't think a
fuel system as you describe could pass muster in a certified airplane for
the reasons mentioned above.

If you must have two pumps (not a bad idea as I've had two fail in about 700
hours) put in a tank selector valve that connects directly to each tank and
put the pumps between the selector and the header. Connect the pumps in
series, as long as they are the Facet style "pump-thru" type, so that should
one fail, the other will be continue to be available. You could merely wire
them in parallel (as I did, since I didn't want to add another switch to the
panel) or wire them so you can select one or the other in case of failure.

With this set-up, you will have full control over fuel useage from each side
plus eliminate the chance of sucking air - which is, IMHO, a good thing. Of
course, it adds the task of managing your fuel, but in balance, that's not
such a big deal.

Cheers,

Dan Schaefer