[MarkSheppard]

Adding a footnote:

Only about 68 x KTs-20 gliders were built 1942-43; and many were destroyed immediately upon completion of their missions:

"The gliders worked the most, helping the partisan detachments. Sometimes up to fifteen heavy gliders were immediately sent at night for the front line to the partisan airfields. They did not return back - the partisans burned them."
-- Pavel Tsybin, chief designer of the KTs-20 and Ts-25.