Hi Udo,

Interesting ... seems like most hard integrated tanks fill from the top
and dump through a separate valve controlled exit out the wing bottom
or through the root through the fuselage. The top mounted cap is
vented to let air out of partially filled tanks as you gain altitude
.... or let air in as you dump. On 27Bs we increase the vent
openings/capacity to support quicker dumping. The top vent is a
problem unless you keep the wings level when you have water. Having a
root vent could eliminate this ...

Lte's see ... soft tanks use a tube vent that is held well above the
tank ... typically to an external outlet ... probably needed as water
sloshing in the bladder can create hydralic pressure ... squirting the
water out of the tank. The vent tubes are typically small ID. Since
the soft tank just collapses when you empty, you don't have to worry
about moving any air back through the vent into the tank to reduce the
vacuum.

So, will a hard tank with a vent potentially have a slow dump rate?
Probably not if your vent tubes/system is large enough. And do you
nave a potential to have air trapped at one end of the tank creating a
high PSI bubble as you gain altitude?

I know you have already figured this stuff out ... :-)

Happy new Year ...

KK






Udo Rumpf wrote:
Has anybody experience with central venting like an ASW 24 but with a
hard
tank. I am preparing the internals of the wings and I would like to
vent
three tanks in on wing independently and join the three vents lines
at a manifold at the root rip and then with a single line up to the
deck.
Comments please.
Regards
Udo

BEGIN:VCARD
VERSION:2.1
N:Rumpf;Udo
FN:Udo Rumpf

REV:20050103T195453Z
END:VCARD