Morgans wrote:
wrote

The Glastar's vents were also at the wingtips, and if the tanks
were full or nearly full, the fuel would run out of the low vent if the
airplane was the least bit off level. Fuel would crossflow through the
system from the higher tank into the low tank and a lot of fuel ended
up on the floor.
The lesson: copy a certified system.

It always seemed like the best place for a vent on a low wing would be up high
on the fin, with a T to supply both tanks equal pressure. Does anybody know of
a certified vent setup like that?
--
Jim in NC

In a high nose-up attitude the vent line might fill with fuel,
and the weight of it might act as a drag on the fuel trying to flow
through the outlet lines to the engine. Not good. There are some
systems with a vent at the wing root above the wing, but these tend to
ice up. Cessna sticks them behind the strut to prevent icing. Not that
we should be flying these tiny airplanes in ice, anyway. Cessna just
has to protect themselves from those who try it.
Designing a trouble-free venting system can be a real pain.

Dan