Drain holes under Schleicher seatpans

I suppoose it depends on what you take as a baseline to measure
improvement from. *

What I believe Schleicher was trying to improve was the shrinkage
problem, by allowing the operator to remove the root rib panels
between long intervals of unballasted flight, as well as the ballast
capacity, needed to get the wing loading up in 18M configuration.

The only problems with the 28 are the rather long dump time even with
the improved double vents of the later models, and the fact that water
drains from the vents if the tips are low. *

The 28 has no shrinkage issues like the 27?

Does the 29 fix both those issues?

Nope. Still drains from the tip, and a dump of 28 gallons required
just under 3 minutes at 75 knots indicated. A full ballast dump would
require between 5 and 6.

I wonder if a one-way flap valve would work in those wingtip vents ...
allow air in but not water out?

I don't know why they didn't put a decent size vent at the root which
I think is what the LS-8 has.

Good question.

-ted