Airworthiness Directive · Amendment 39-22339 · Drag control system
Schempp-Hirth Flugzeugbau GmbH Gliders
This AD applies to Schempp-Hirth Flugzeugbau GmbH (Schempp-Hirth) Model Duo Discus and Duo Discus T gliders, all serial numbers, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for all Schempp-Hirth Flugzeugbau GmbH Model Duo Discus and Duo Discus T gliders. This AD was prompted by mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI identifies the unsafe condition as the airbrake becoming blocked or jammed in an extended position during high airspeed due to an incorrect adjustment on the airbrake system. This AD requires repetitively inspecting the airbrake system and taking corrective action as necessary. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 12 months after the effective date of this AD and thereafter at intervals not to exceed 12 months, inspect the airbrake system for smooth operation, for sufficient airbrake panel overlap, and for proper cockpit control adjustment in accordance with Section I, and either II or III, depending on your glider configuration, of Schempp-Hirth Flugzeugbau GmbH Maintenance Information SHK-M-01-22 for the Duo Discus and Duo Discus T airbrake system, dated January 26, 2022.
Note 1 to paragraph (g)(1): Schempp-Hirth Flugzeugbau GmbH Technical Note 396-21, dated January 26, 2022; and Schempp-Hirth Flugzeugbau GmbH Technical Note 890-17, dated January 26, 2022, contain information related to this subject.
(2) If, during any inspection as required by paragraph (g)(1) of this AD, any part of the airbrake system is not properly adjusted, before further flight, adjust the airbrake system in accordance with a method approved by the FAA; the European Union Aviation Safety Agency (EASA); or Schempp-Hirth's Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
