EASA AD No.: 2010-0160-E

EASA Form 111 Page 1/3 

## EASA EMERGENCY AIRW ORTHINESS DIRECTIVE

AD No.: 2010-0160-E

Date: 30 July 2010

Note: This Airworthiness Directive (AD) is issued by EASA, acting in accordance with Regulation (EC) No 216/2008 on behalf of the European Community, its Member States and of the European third countries that participate in the activities of EASA under Article 66 of that Regulation.
This AD is issued in accordance with EC 1702/2003, Part 21A.3B. In accordance with EC 2042/2003 Annex I, Part M.A.301, the continuing airworthiness of an aircraft shall be ensured by accomplishing any applicable ADs. Consequently, no person may opera te an aircraft to which an AD applies, except in accordance with the requirements of that AD, unless otherwise specified by the Agenc y [EC 2042/2003 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, Article 14(4) exemption]. 

### Type Approval Holder’s Name :
Aircraft Industries, a.s. Type/Model designation(s) : L-13 and L-13 A BLANÍK sailplanes

TCDS Number: EASA.A.024

Foreign AD: Not applicable
Supersedure: This AD su persedes EASA AD 2010-0122-E which superseded EASA AD 2010- 0119-E dated 18 June 2010.



### ATA 57 Wing – Wing Main Spar – Inspection / Operational Limitation / Operational Records Check

Manufacturer(s): Aircraft Industries, a.s, LE T k.p., LET a.s. and LETECKÉ ZÁVODY a.s.
Applicability: L-13 and L-13 A BLANÍK sailplanes, all serial numbers.

Reason: A fatal accident occurred to a L-13 BLANÍK sailplane, in which the main spar of the right wing failed near the root due to positive load. The right wing detached from the aircraft and the pilots lost control of the sailplane. The preliminary investigation has reveal ed that the fracture may have been due to fatigue. The AD 2010-0119-E required immediate inspection of the main spar at the root of the wing to detect fatigue cracking and the accomplishment of the relevant corrective actions as necess ary. In addition, this AD 2010-0119-E imposed operational limitations. AD 2010 -0122-E retained the requirements of AD 2010-0119-E, which is superseded, and extended the applicability to L-13 A BLANÍK sailplanes. The requirements of AD 2010-0122-E were considered as interim action to immediately address the unsafe condition. Since issuance of AD 2010-0122-E, based on further information provided by the Austrian Accident Investigation Board, EASA has re-assessed the inspecti on method as described in Aircraft Industries a.s. Mandatory Bulletin No. L13/109a. EASA now co ncludes that the inspection method might not be sufficient for detecting the crack which means that the unsafe condition might still be pr esent even if the sailplane has passed the inspection required by AD 2010-0122- E. Furthermore, the Type CertificateEASA AD No.: 2010-0160-E

EASA Form 111 Page 2/3 Holder indicates that it is extremely important to remain within the flight limitations specified in the Aircraft Industries a.s. Mandatory Bulletin No. L13/109a. For this reason, this AD further requires a record checking for determining if the sailplane has been op erated within the flight limitations.

For all the reasons stated above, as a precautionary measure, this AD is prohibiting operations when a sailplane does not pass the requirements of this AD. For those sailplanes, EASA is currently working with the Type Certificate Holder. When, as a result of the on-going investigation, a solution is later identified, further mandatory action is likely to follow.

Effective Date: 01 August 2010

Required Action(s) and Compliance Time(s): Required as indicated unless previously accomplished: (1) After 18 June 2010 [the effective date of AD 2010-0119-E] for L-13 BLANÍK sailplanes or after 23 June 2010 [the effective date of AD 2010- 0122-E] for L-13 A BLANÍK sailplanes, all aerobatics manoeuvres (ie. Roll (Výkrut), Loop (p ř emet), Stalled turn (souvrat), Immelmann turn (p ř ekrut), Half roll (zvrat), Inverted fli ght (let na zádech)) are prohibited. The chapter “aerobatics” in Flight Manuals listed below is invalid. - Do-L13.1111.1 (In Czech language) - Do-L13.1111.3 (In English language) - Do-L13.1111.2 (In German language) - Do-L13.1111.4 (In Spanish language) - Do-L13.1111.5 (In Russian language) Before next flight after the effective of this AD, take the following actions: (2) Insert this AD in the sailplane ́s Flight Manual and inform the pilots accordingly. (3) Carry out an inspection of the wing critical areas in accordance with Aircraft Industries a.s. Mandatory Bulletin No. L13/109a “Checking of the connection of the bottom wing suspension with spar cap – review of the operation conditions”. (4) An inspection that has been accomplished prior to the effective of this AD in accordance with Aircraft Industries a.s. Mandatory Bulletin No. L13/109a “Checking of the connection of the bottom wing suspension with spar cap – review of the operation conditions” is acceptable to comply with the requirement of paragraph (3) of this AD. (5) If any cracks are detected during the inspection required by paragraph (3) of this AD, no further flights are permitted. (6) Check the sailplane record and determine the following:

To be determined Ratio
Ratio between Aerobatics Flight Hours (FH) and total accumulated FH since new. 2%

Ratio between Total number of winch launches (WL) and total accumulated FH since new. 5 WL/FH

Ratio between Dual FH and total accumulated FH since new 50%
If any ratio is exceeded, no further flights are permitted. (7) If the sailplane records are missing or incomplete, no further flights are permitted.EASA AD No.: 2010-0160-E

EASA Form 111 Page 3/3 (8) Submit the information requested by Mandatory Bulletin No. L13/109a to Aircraft Industries a.s. for further assessment.

Ref. Publications: Aircraft Industries a.s. Ma ndatory Bulletin No. L13/109a “Checking of the connection of the bottom wing suspension with spar cap – review of the operation conditions”, issue 1 dated 18 June 2010 The use of later approved revisions of this document is acceptable for compliance with the requirements of this AD.

Remarks : 1. If requested and appropriately substantiated, EASA can approve Alternative Methods of Compliance for this AD. 2. The safety assessment has requested not to implement the full consultation process and an immedi ate publication and notification. 3. Enquiries regarding this AD should be referred to the Airworthiness Directives, Safety Management & Re search Section, Certification Directorate, EASA. E-mail: ADs@easa.europa.eu

. 4. For any question concerning the tec hnical content of the requirements in this AD, please contact: Aircraft Industries, a.s. - Na záhonech 1177, 686 04 Kunovice, Czech Republic Telephone: +420 572 817 660, Fax: +420 572 816 112 Email: ots@let.cz