Message-ID: <004201bfb0d4$ecd80a80$0200005a@csc.com>
From: "Denis Conkey" <dconkey@itcreators.com>
To: <lancair.list@olsusa.com>
References: <20000428041914.AAA21269@ns1.olsusa.com>
Subject: Header Tank Fuel
Date: Thu, 27 Apr 2000 22:45:12 -0700
Mime-Version: 1.0

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I've been watching the discussion regarding the pros and cons of having a
header tank and finally have to add my comments if you are not to sick of it
by now.  It seems to me (I may be wrong on this) that most of the negative
comments are from folks that have little or no time flying with the header
tank system.  I have over 400 hours flying with my Lancair 235 (IO-320) and
have never once had a problem where I have had too little fuel in the header
tank and have rarely overfilled it (happened a few times early on, but now
it's just part of my second nature scan to check the level...as you would
your fuel gauge for your wings).  We (I have a partner in the airplane) have
installed a low fuel switch which lights a very bright amber light that
can't be missed when the header tank gets down to about 7 gallons.  This is
more than enough fuel to get me to even a distant field.

However, the best thing I like about this system is even if I have a failure
of one or even both wing pumps (hopefully never happen) I would know exactly
how much fuel I have.  In addition, when I'm trying to stretch my legs and
need to know near the end of the flight exactly what fuel I have, it's nice
to see it in the header tank, rather than relying on some gauge in the wing
tank being accurate.  On more than a few long flights that I have flown, I
have exhausted both of my wing tanks and was left with only the fuel in the
header tank, and it was great knowing exactly how much fuel I had to work
with.  I'm not sure you can count on that and have the safety margin with
just monitoring the gauges for the wing fuel.  Trust the gauges all you
want, but I like seeing the fuel.  This is certainly my opinion, which I'm
sure won't be shared by all, but certainly some that have experience with
the system.  As for work load, I really feel that this does not add
appreciably to my load at all.  As I'm nearing my destination, I've already
made sure that header is topped and there is really nothing to monitor past
that point with regard to fuel.

> attention grabbers, can get burned.  Tony Bingelis got it right when he
said
> the best fuel
> system is the one where the pilot is not involved and so it is with many
> fighter jets.  "Kick
> the tires, light the fires and the first one to the runway leads", is the
> humored statement of
> many fighter jocks.  I just seems to me,  a fuel system allowing that kind
> of freedom of
> operation can be created without a lot of high tech stuff.

As for Fighters, I have over 2,200 hours in an F-14 Tomcat and yes you can
push the throttles and just go, but don't be fooled that it is even close to
a simple system that is hands off.  On more than a few occasions, there have
been F-14s that have flamed out with useable fuel in the aircraft.  It is a
fairly complex system with some built in overrides and numerous cross feed
and vent valves and a number of override switches in the cockpit, not to
mention the problems that occur with the tanks if those were being carried.
It was possible to run out of fuel to the engine with more than 4,000 pounds
of fuel still in the airplane.  While not common, it did happen.

...Denis
N235WC (Over 650 hours on the airplane now and going strong)


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