On Wed, 3 Oct 2007 17:50:35 -0400, "Morgans"
wrote:


"Peter Clark" wrote

AIUI, it's because they're bladders and folds on the bottom could
gather water. If it was a wet wing they wouldn't need as many, like
the older models.

But they are wet wings, in question, AFAIK. Did you see the picture that
someone posted in a link? Each rib was forming a little damn that could
possibly trap a small amount of water, so a drain was installed to drain any
trapped water, in each bay.

The airfraft in that link is a 1982 172P, not a new (post-restart)
172R/S, 182T, etc with bladders in the wings. It's been a while (and
the only older model 172 I've flown is an M model) but I thought the
pre-restart aircraft only had 2 sumps at the wing root and a stariner
drain pull-thingie in the oil door?

You have the same issue as that 172P with the Malibu. Since they're
wet wings, the only path water has to flow underneath the ribs is the
minute clearance between the ribs and the lower wing skin. At least
the Malibu has some pretty significant dihedral. But if the aircraft
hasn't been sitting for (I'm not going to try and test it) some large
number of hours, unless you're pumping in almost pure water I doubt a
significant sample of water would show up in the 1 sump at the wing
root from fueling during quick (1hr or less) refueling stops during
multi-leg flights.