From: Sky2high@aol.com
Message-ID: <e334763d.361ebaec@aol.com>
Date: Fri, 9 Oct 1998 21:39:56 EDT
To: lancair.list@olsusa.com, RTWM02A@prodigy.com
Subject: Old 320/360 fuel system drawbacks
Mime-Version: 1.0

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Stuart Seffern sends:

<<The old fuel system in the 360 has its drawbacks too.

1. Flying high above a solid 8000 ft cloud deck IFR over lake Erie 
last year I found that pushing the com transmit button dimmed the 
panel.  Arg!  Battery dead, alternator could not keep up, breaker 
out!  Reset, popped again 5 minutes later, shut down all unnecessary 
power.  Popped again in 2 minutes.  Fuel: 40 gals on board.  Usable: 
now 7 gallons!  9,500 ft. 40 miles from shore!!  Enough for one 
successful approach. 

It could happen to you... 

What about a parallel system that could get to the remaining fuel?  
One without giving up the simplicity of no fuel selector.  Ideas?  (..
. a small seperate 12 v.batt to another fuel pump? )>>

Stu:

You are discussing an electrical problem, not a fuel problem.  I will restate
-- My header tank is always full, giving me at least one hour.  

On the electrical side, I utilize all of the normal warnings to indicate an
electrical problem such as low voltage, high discharge, alternator out, etc.
I also have an essential bus system -- gear down lights, engine instruments,
Com1, Xpdr, GPS( it has it's own backup battery), panel flood, etc. -- that
bypasses the master relay to directly access the battery (like magnetos
generate their own electricity).  So, If I have a major electrical problem, I
can shut down the Master Switch and use whats left of the battery to find an
airport.  Essential bus systems are designed to provide protection for some
major electrical system problem that might not involve certain isolated
essential items, such as gear down lights, engine instruments, and a few
others.  Non-essential items are: fuel pumps, external lights, flaps, gear
motor, Com2, etc.

Scott Krueger
N92EX

P.S.  I also fly a Skymaster, a single engine with a spare in the back (or the
front, depending on which one is running), that has redundant systems for
almost everything electrical (two alternators, two voltage regulators, a
2-Dcell battery restart system for the alternators, etc.) except that ALL (yes
ALL) of the internal lights (dimmer circuits, switch lights, map light, flood
light, post light, instrument light and dome light) are on ONE (yes ONE)
circuit breaker.  At night, a short in a sub circuit of this system leaves you
with your flashlight in your mouth until you can find the ground.  Been there,
done that, one more reason to dislike type certified planes cause you can't do
much about their inadequacies.

P.P.S
I get about 25 miles per gallon.  I could get somewhere with 7 gallons.