Date: 202109
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: CLEAR; 15
Aircraft: Sail Plane
Operator: FBO
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Parked
Airspace: Class E ZZZ; Class G ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Aircraft Logbook(s)
Component problem: Improperly Operated
Reporter organization: FBO
Reporter function: Pilot Flying; Flight Engineer / Second Officer; Instructor
Reporter qualification: Flight Crew Flight Instructor; Flight Crew Glider; Flight Crew Multiengine; Flight Crew Instrument
Human factors: Communication Breakdown; Situational Awareness
Second reporter function: Instructor
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Routine Inspection
Result: General Maintenance Action
Contributing factors: Human Factors; Procedure; Aircraft
Primary problem: Procedure

Narrative: After glider Aircraft X was returned to service to our glider club after a new paint job and annual inspection; it's maintenance logbooks were secured in club safe and the glider was reassembled and marked OK for flight on our status board. As a result; the glider flew multiple times post annual inspection for glider club operations; including student pilot training operations.Without access to the maintenance logbooks; pilots; including myself; had no way of verifying first hand the maintenance status of the glider other than the club's maintenance status board which had the glider in a green status.This situation can be prevented by better communication between certified mechanic and club representative after completion of annual inspection or making making maintenance logbooks available to pilot's prior to flight.


Second narrative: At the most recent annual inspection; unbeknownst to me; the AI (Aircraft Inspector) had not signed off the glider for return to service; noting some discrepancies. Due to apparent miscommunication between the mechanic and the club; the club had since assembled the aircraft and returned it to service; marking it airworthy and ready for use on the club equipment status board. The aircraft airframe logs were locked in the club safe along with other documentation.Recently; this miscommunication was found out and it so happens that the glider was used for instruction by myself and other club instructors in the interim.The club has discussed ways to both mitigate the status of the aircraft and necessary actions to return it to airworthy status; as well as measures to prevent this from happening in the future. As one of the measures; the club has decided to include a copy of most recent inspection sign off in the aircraft flight binder so it is readily available for the PIC to determine airworthiness of the aircraft.


Synopsis: Instructors and a student pilot reported lack of access to maintenance logs caused an aircraft to be operated in a non airworthy condition and suggested changes to the club's procedures to mitigate this.