A member of my gliding club owned an ASW-12, so I've seen one up close, helped rig it (very heavy wings) and seen it flying many times.
The ASW-12 was one of the early production glass-fibre gliders and was developed from the earlier D-36.
https://en.wikipedia.org/wiki/Schleicher_ASW_12
https://en.wikipedia.org/wiki/Akafli...adt_D-36_Circe
It's a very elegant Open Class glider, 18 m span and a 46:1 glide ratio, which was very impressive for the 1960s. Hans-Werner Gross used an ASW-12 in 1972 to set an absolute World Free Distance Record, flying 1461 km flight from Lübeck to Biarritz. His record stood for thirty years.
What is not clear from the Wikipedia write-up is that performance was the primary design goal. Many other aspects of the design were compromised in pursuit of that goal. The low-cockpit height means that the pilot is almost lying flat; there is no suspension in the main gear; there are contour-changing flaps but no high drag setting for landing; there are no spoilers; the only high-drag landing aid is a tail parachute, which was prone to failing if it got wet during flight.
As a consequence of the design compromises, the ASW-12 was very difficult to land.Our club member, the owner of CF-ASW, did not use the tail parachute. Instead, he would fly downwind at about 300' and then on base-leg, to increase the drag,he would use a side-slip until just before landing. It was scary to watch. Just to add to the workload, when using a maximum sideslip, the rudder would aerodynamically lock at full travel, requiring a rudder-pedal push to re-centre it!
I read an article in Soaring many years ago, that stated that a large percentage of ASW-12 owners, crashed it on their first flight!
As I said, I never had any ambition to fly one.