Hi! Nigel /All
I hear your concerns, Nigel, all very very real. I don't have the two pump
situation since my checklist for take off and landing includes switching on
the back up pump to the mechanical engine pump, anyway.
However whilst your proposal is well founded I would query how you know
which side of the tank your system is pulling from? (Could it be on reserve
and you be unaware?)
In the event of an approach to land with fuel levels "close" the reserve
should be switched on as part of your landing checks.
Further consideration is the fact that should contaminated fuel be
inadvertantly put into the main tank the most likely place for it to lay is
in the reserve side, so it is an absolute necessity to switch to the reserve
tank in advance of the port side of the "saddle" becoming empty. I would
recommend as a matter for regular procedure that periods of flight at a safe
height switched to the reserve /starboard side be conducted after filling
the tank
Just an observation for consideration by those following ....
Best regards
Bob Harrison G-PTAG Europa MKI 337 /Jabiru 3300
-----Original Message-----
From: forum-owner@europaclub.org.uk
Subject: Re: Gates fuel lines
Message text written by Fred Fillinger
>If ever in a minimum fuel situation, it would
appear to be wise to run the main down as low you dare, to stretch
potentially limited usability of the reserve. And prior thereto,
verifying fuel flow on the reserve side by temporarily switching.
<
This is one of the reasons I opted for a parallel fuel system. If you are
that short of fuel you may have other demands for your attention outside
the aircraft (ie sorting out somewhere to land expeditiously). Running the
main side low relying on manual changeover just before the engine coughs is
not my idea of fun. Much better to have a low pressure switch at the main
pump output to sense the lack of pressure and bring on the other pump
feeding from the other side for you. This way a main pump failure in the
cruise (or line blockage, leakage or vapour lock) will be automatically be
handled by the system preventing unnecessary engine shutdown.
Nigel Charles
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