| 501-1 | Wear of rudder control cables in the area of S-shaped guides of rudder pedals | | German | |
| 501-01-2 | Color coding scheme: affixing of different/additional colors. German registered sailplanes | | German | |
| 501-2 | Elevator linkage at base of the control stick | Latest 31/12/1980 | German | English |
| 501-3 | Replacement of rudder drive gimbal rear actuator arm | Latest 31/3/1987 | German | English |
| 501-4 | Replacement of "DIN" control cables with "LN" cables | Latest 1/6/1987 | German | English |
| 501-5 | Modification of Airspeed indcator limits. Reduction to VNE 200Km/h /108Kt/124mph | | German | English |
| 501-6 | Tow releases: Optional use of model E85 instead of E72/E75 | | German | English |
| 96-134 | 501-7 | Inspection of glass fiber laminate on spar stub fitting | | German | English |
| 96-140 | 501-8 | Weight and static moments of control surfaces after repainting and repair | | German | English |
| 501-9 | Installation of Mode-S-Transponder and Transponder Antennas | | German | English |
| EASA AD 2011-213 | 501-10 | Inspection / replacement of elevator control rod in vertical fin | | German | English |
| 501-10 | Authorised service facilities for TN 501-10 | | German | |
