# FAA MCAI INFORMATION FORM To: Airworthiness Authority of EASA

**Aircraft Certification Service Federal Aviation Adm** **inistration In support of the FAA’s actions to**  **address your country’s**  **mandatory continued airworthiness inform ation (MCAI)**  **in the United States, please provide the item** **s highlighted below by , if not contained in the**  **referenced airworthiness directive (AD) or service inform** **ation.**
**Aircraft Manufacturer/Model ECAA AD/Revision No./Date**  **Service Bulletin/ Revision**  **No. /** **Date** EUROCOPTER AS350 AD 20 1 3
- 0 1 33 ASB 05.00. 74 B, BA, BB, B1, B2, and D Ju ne 28 , 201 3 Ju ne 25 , 201 3 EUROCOPTER AS355 AD 20 1 3
- 0 1 33 ASB 05.00. 65 E, F, F1, F2, N Ju ne 28, 2013 Ju ne 25, 2013 **1. Describe the unsafe condition, and its root cause. I**  **nclude description of how the problem could affect the safe operation of the airplane.**  Eurocopter have been informed of a case of crack detection on the yoke of a TRH pitch horn. The investigation of this occurrence is on
- going and the cause has not yet be en determined. This condition, if not detected and corrected, may eventually lead to the failure of the two horn yokes, resulting in the loss of the anti
- torque function, possibly resulting in loss of control of the helicopter. To address this condition, Eurocopter issued Emergency Alert Service Bulletin (ASB) No. 05.00.74 for AS 350 helicopters and ASB No. 05.00.65 for AS 355 helicopters. Shortly thereafter, these ASBs have been updated and reissued by Eurocopter at Revision 1 to clarify that the affecte d TRH pitch horns can be identified by means of either assembly P/N’s or part P/N’s marked thereon and to implement a documentary change to some of tail rotor blade assembly log cards. For the reasons described above, this AD requires repetitive visual in spections of the affected TRH pitch h orns to detect cracks and, depending on findings, replacement with a serviceable assembly. This AD is considered an interim action and further AD action may follow. **2. Provide the number and description of occurrences w**  **hich prompted the AD.** 1 case
. **3. What is the compliance time, and consequences if**  **extended ? What would be considered an**  **appropriate grace period for compliance.** According to the Airworthiness Directive (AD) **4. Cost of part and/or installation**  **work hours fo**  **r the ow**  **ner/operator (data from the manufacturer and their supplier, if**  **applicable) .** **5. If** 

**parts are required, are they available for all aircraft s**  **?** According to the Airworthiness Directive (AD) 6. **What category best describes the cause of the unsafe condition**  **:** unchanged **Design problem**  **quality control problem operational**  **Maintenance unapproved parts**  **other ( s**  **pecify** : not identified **7. Should a ferry flight be**  **permitted? If**  **no, why not?**  **Yes No**  **8. Number of aircraft affected, b**  **y model designation and serial number (U.S**  **. registered and worldwide)**  **.** US registered: approximately 695 AS350 World

-wide: approximately 2842 AS350 US registered: approximately 96 AS355 World

-wide: approximately 641 AS355 **9. Is further action**  **anticipated to**  **be necessary to correct this unsafe condition?**  **If so, please provide**  **description and recommended compliance time.**

**10. Other**