S10/12 EASA AD 12AK Clutch

August 11, 2022 | 2021-0278R1

Occurrences have been reported of unintended slipping of the freewheel clutch (P/N 12AK) during operation and, subsequently, overheating (burnishing) of the friction pads inside of the clutch. This condition, if not corrected, could lead to total loss of thrust, possibly resulting in loss of control of the powered sailplane. Even after a successful implementation of the recommendations for safe operation of the clutch, published in Stemme AG Service Information P064-8900057/01, it has been determined that loss of thrust could occur without signs in advance.