AIRWORTHINESS DIRECTIVE

CAA-AD-025/2001R1

Supersedes CAA-AD-025/2001

Date of issue: April 04, 2001

ENGINE - TIME TO OVERHAUL - CORRECTION

Applicability: All M332; M337, A, AK; M137A, AZ engines produced till June 30, 1991 on which till this time overhaul has not been performed or the latest overhaul was performed before January 1, 1999 and at the same time on which following Information Service Bulletins have not been performed:

M337/76b, M337A/10b, M337AK/5b, M137A/15b, M137AZ/8b

M337/78b, M337A/11b, M337AK/6b, M137A/16b, M137AZ/9b

M332/68b, M337/79b, M337A/13b, M337AK/8b, M137A/18b, M137AZ/11b

M337/87b, M337A/19b, M337AK/14b, M137A/24b, M137AZ/17b

Reason: This AD is issued for the TBO correction mentioned in the applicable Technical Specifications that have been issued by LOM Praha s.p., Černokostelecká 270, 100 38 Praha 10 – Malešice; IČO 00000515, Type Certificate No.: 92-08, 94-06, 96-02 holder. This TBO was not accurate because this time is right after performing Information Service Bulletins mentioned in part Applicability of this AD only.

After correction in Technical Specifications, the basic TBO is valid for mentioned engines:

- 800 flight hours during 15 years from the first installation on the aircraft under not exceeding of corrosion protection limits performed after finishing of production by producer (or service station for overhaul) of engine in case of using mineral oil mentioned in Technical Specifications.

- 1000 flight hours during 15 years from the first installation on the aircraft under not exceeding of corrosion protection limits performed after finishing of production by producer (or service station for overhaul) of engine in case of disperse ashes free (additive) oil mentioned in Technical Specifications.

Effective date: May 17, 2001.

Compliance: Operators or owners of all aircraft on which those engines are installed, or approved maintenance service stations, which can work on dismounted engines, will check if real operating time does not exceed those TBO. This inspection must be recorded into Aircraft Technical Documentation (Engine Logbook).

Remarks:. The compliance of this AD must be recorded in Engine Logbook, where applicable the requirements of this AD must be integrated into Aircraft Technical Documentation. Address inquiries concerning this AD to: Civil Aviation Authority, Airworthiness Division, Ruzyne Airport, 160 08 Prague 6, Czech Republic, tel: 420 2 33320922, fax: 420 2 20562270

Ing. Pavel MATOUŠEK
Director of Airworthiness Division
CAA CZ