Message-ID: <19981231012347.14783.qmail@www04.netaddress.usa.net>
Date: Thu, 31 Dec 1998 01:23:46
From: Dan Schaefer <dfschaefer@usa.net>
To: lancair.list@olsusa.com
Subject: Facet pumps
Mime-Version: 1.0

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In regard to the comment (question?) about the literature that comes
with the Facet pumps and the warning that it's not for aircraft use. 

The number one reason for that statement is CYA by the company. 
Secondarily, they know that their pumps have not been certified for
any "regular" airplane - these people probably never heard of a homebuilt
- and it's Lawyer Speak in that regard.

I have three of these on N235SP and have had one failure. I can't really
put the onus on Facet as the failure came right on the heels of an
inadvertant shut-down of the battery contactor while the alternator stayed
powered up. The system voltage, without the filtering effects of the
battery (even for the three or four seconds before I realized my error
and turned the battery back on), must have spiked to destructive levels.
So, I don't blame the pump, it just can't take that kind of abuse.

The three Facets in my airplane are used as follows: One on the firewall
as the boost pump in series with the mechanical pump on the engine; Two
pumps in series under my seat following the Left-Right selector valve.
I'm not sure I'd rely on any non-certified pump as the only source of
fuel pressure, i.e., without the mechanical pump, but as the back-up to
the engine driven pump, I feel pretty safe. Two serial failures in the
same system on the same flight has a very low probabliity. The two in
series for transfer are there to provide the required (by me) redundancy -
again, two simultaneous failures, etc, etc.

I gave some thought to what it would be like to have one xfer pump for
each wing and have one fail. I'd be flying around with a full wing tank
and couldn't get at it, and to make things more interesting, you'd have
one heavy and one light wing pretty quickly. With the two pumps *following*
the selector valve, I can get all my fuel in both wings even with a single
xfer pump failure.

And as far as those warnings that come with the product, Facet is trying
to forestall any liability claims should some smart-aleck use one of
their pumps in an airplane. They aren't the first ond only manufacturers
to do so. As far as I'm concerned, I'd provide the same level of
redundancy in my fuel system no matter Who's pump I used.

Get it flying!

Dan Schaefer
N235SP
(A real gas!)