Andrew;
If I were to do it over again I would form several brackets or pockets of formed
fiberglass to hold the tank in place but not be bonded to the tank. Look at
the corners of the tank by the tunnel. Brackets formed there would be very
stiff
because of the 90 degree angle. Forming a contour along the module at the
radiused edge of the tank would give lateral support. I also thought that
bonding
some aluminum angle to the module where the top of the tank's ledge would
rest on would be good to inhibit forward and back rocking movements. That foam
as a compliant surface is right on the mark where anything touches the tank.
All edges of any brackets should be radiused away from the tank so that the edge
is pointed away from the tank,
Steve Hagar
A143 Mesa AZ
-----Original Message-----
>From: Andrew Sarangan <asarangan@gmail.com>
>Sent: Dec 5, 2013 11:01 PM
>To: Europa List <europa-list@matronics.com>
>Subject: Europa-List: Alternative fuel tank mounting?
>
>I am hoping someone can comment on an alternative tank mounting
>strategy. A picture of what I am thinking is attached.
>
>To avoid any potential stresses developing due to tank expansion, I am
>thinking of horizontally bracing the fuel tank against the baggage
>bay wall using two fiberglass straps all the way around the tank - one
>strap below the tank ledge and the other just above the outlet bosses.
>These straps are for simply maintaining the fore/aft and lateral
>position of the tank. Vertically, the tank will simply sit on the
>fuselage floor. The tank bottom is nearly flush with the baggage bay
>floor, so it should sit nice and even on the fuselage. With this
>setup, I have satisfactory clearance between the spars, pitch tube and
>the tank outlets. I plan to add a thin neoprene pad around the tank
>bottom to make sure there are no hard points of contact between the
>tank and the fuselage. The neoprene is oil resistant, non-absorbent
>and has fire resistance.
>
>Since this is such an irreversible step, I want to make sure I am
>thinking this through correctly. Probably the larger questions are,
>will the fuselage floor be able to take the entire tank load? Is there
>any issue with letting the top portion of the tank (the ledge)
>floating with no vertical support?
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