I have been thinking about the advisability of buying a 50 year old Glider and several things came to mind. There were 3, first generation ships, Diamont, Phoebus and 301 Libelle. Two of them used balsa wood wing core and the other didn't use any core at all (Diamont 16.5 & 18) and one used a wooden box spar (Phoebus). The next generation of sailplanes didn't employ any of these construction methods! The next generation (ASW-20, etc.) was built about 40% stronger after the LBA changed the strength requirements for their sailplanes. As an example, the Phoebus uses 3 layers of 4 ounce cloth in their fuselage (and wings) while the 20 uses a minimum of 3 layers (or more) of 6 ounce cloth in their fuselage. The question becomes, Is the Phoebus built strong enough? Yes, but the integrity of the wooden based box spar must not be compromised! What could compromise the integrity of the box spar? A ground loop that resulted in a split seam for a few feet. Pilot probably got out and was relieved to see the T tail still standing proud. He probably made a careful inspection, looking for any cracks and decided all's well, that end's well, right? A split seam in the box-spar can't be seen from the outside! Something else that could weaken a box-spar is wood rot, can't see that from the outside either. We know the ship has been stored in the rafters for 15 years, but how was it flown and stored before that? The ship may not be a bargain at any price!
I've been remembering the tragic crash of BG-12, that a new pilots dad had perched for his son. The kid made a high speed pass, like he'd seen the big guys do, then pulled on the flaps (probably going too fast), the inboard hinge of one flap gave way and took out the drag spar! That allowed the wing to twist and one wing departed the aircraft! Wood rot was found in the drag spar!
Buyer be ware!
JJ