Craig,
That is a very interesting solution, if I understand you correctly:
- You have the original Europa tank inside the CM
- You cut the head rests off
- On top of the CM you then place the independant reserve tank
- On top of this (probably bonded to the CM) comes low head rests,
height adjusted for good angle of the shoulder belts
- The independant top tank feeds the engine (via suction side of
electric fuel pump), so that if you should experience a crack in the
original tank you still have 28 litres of fuel
- Topping off the independant tank by the fuel return is ingenious - you
then avoid dumping unused fuel at the rate of about 9 litres per hour
(that's how much goes through the return line even with the very narrow
orifice in the line) through a cracked original tank
Questions:
- How will you fill up the top tank before flight - through the standard
filler neck somehow, or through a filler opening on its top?
- Wrapping of the alloy tank by vinyl ester resin: I assume this is how
you will build the extension of the seat back and the CM back/sides and
the new top, plus the new headrests. Will you wrap it closely to the
alloy tank to add strength, and make this new "box" tight so that you
have an extra barrier in case the alloy tank should spring a leak
somehow (I assume so, since you will use vinyl ester which should stand
up well agains gasoline)?
- How does vinyl ester bond to the epoxy used in the original CM
structure (I am totally ignorant on this, so I am not implying any
doubt)?
- Have you done the design of the alloy tank and its fuel in/out
connections yet, and figured out how to make the new headrests, etc.?
I think your solution is much better than tearing out a working original
tank before it cracks (if it ever does), and would be a nice winter
project (when are we ever declaring our airplanes "completed"?!).
Best regards,
Svein
----- Original Message -----
From: craig bastin
To: europa-list@matronics.com
Sent: Thursday, June 19, 2008 10:48 AM
Subject: RE: Europa-List: Fuel tank dimensions
I am doing the same as you suggest Svein, and have allowed for it when
building the CM and the fuel system. Now that the top of the fusealage
is bonded on, the top of the seats is coming off and i am lifting it
up 110mm, one reason is to fix the seat belt issue, the other is to
allow for a second tank sitting on top of the main tank, total volume
is 28 litres, giving almost 100litres total, it fills from the return
line
on the engine and is set up to be an independant reserve tank, so any
fuel in there has already been filtered by the main gascolator. and is
then
run through a second gascolator between the reserve tank and the fuel
selector. When the reserve tank is full it overflows back into the main
tank. Tank is 1.5mm alloy wrapped in glass using vinyl ester resin,
which is what the glasair's are made from and they run wet wings with no
lining
(according to a builder I visited)
craig
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