Disclaimer. These files have been provided from various sources and no warranty as to their accuracy is given. Pilots should not rely on this information and should satisfy themselves as to the usefulness of the information.
RTFM! Manufacturers send out Airworthiness notes and directives whenever required and these notes do not necessarily contain the latest information.
Club briefing notes are no substitute for the flight manual, but are sometimes more succinct or written in something passing for English.
Many glider manuals are depressingly thin and combine breathless hyperbole from the marketing department ("Pilot fatigue...has been virtually eliminated because of the semi-reclining adjustable seat...") with blinding glimpses of the obvious (we learn that the Pegasus "tail is a T type").
Machines from non-English-speaking countries have novel features described in equally novel English (when flying the L-23 you should "reckon with the mild sailplane emerging in the case of the higher approaching speed").
Persevere: buried in amongst all these distractions will be nuggets of hard data that you actually need to know.
For instance, have you ever wondered why the yellow "minimum approach speed" bug on the Blanik L-23 air speed indicator is at an infeasibly low 41 knot indicated air speed? Page 4.14 of the flight manual reveals all: this is apparently the minimum approach speed with the air brakes closed. If you're one of those peverse and demanding pilots who actually uses air brakes, stay with that 50 knot indicated air speed still-air minimum approach speed your instructor told you about.