EASA AD No.: 2010-0160-E 

EASA Form 111 Page 1/3

EASA EMERGENCY AIRWORTHINESS 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 operate an 

aircraft to which an AD applies, except in accordance with the requirements of that AD, unless otherwise specified by the Agency [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Supersedure: This AD supersedes EASA AD 2010-0122-E which superseded EASA AD 2010-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, LET 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 revealed 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 necessary. 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AD 2010-0119-E, which is superseded, and extended the applicability to L-13 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 inspection method as described in Aircraft 

Industries a.s. Mandatory Bulletin No. L13/109a. EASA now concludes that the 

inspection method might not be sufficient for detecting the crack which means 

that the unsafe condition might still be present even if the sailplane has passed 

the inspection required by AD 2010-0122-E. Furthermore, the Type Certificate 
EASA 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 operated 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 (přemet), Stalled turn (souvrat), Immelmann turn 

(překrut), Half roll (zvrat), Inverted flight (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. Mandatory 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 immediate publication and notification. 

3. Enquiries regarding this AD should be referred to the Airworthiness 

Directives, Safety Management & Research Section, Certification 

Directorate, EASA. E-mail: ADs@easa.europa.eu. 

4. For any question concerning the technical 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