AD 2017-11-08 Airworthiness Directives; Diamond Aircraft Industries GmbH Airplanes

Makes named: diamond, technify. Models named: DA 42. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to Diamond Aircraft Industries GmbH Model DA 42 airplanes, serial numbers 42.004 through 42.427 and 42.AC001 through 42.AC151, certificated in any category, that have: (1) either a TAE 125-02-99 or TAE 125-02-114 engine installed; and (2) either DAI part number (P/N) D60-9078-06-01_01 or Technify P/N 52-7810-H0014 01 engine exhaust pipes installed.

Unless already done, do the following actions. (1) Before or upon accumulating 40 hours time-in-service (TIS) on the affected engine exhaust pipes or within the next 10 hours TIS after the effective date of this AD, whichever occurs later, and repetitively thereafter at intervals not to exceed 50 hours TIS, inspect each engine exhaust pipe following Diamond Aircraft Industries GmbH Mandatory Service Bulletin MSB-42-129, dated May 17, 2017. (2) If any crack(s) is/are found on any engine exhaust pipe during any inspection required by this AD, before further flight, replace the affected engine exhaust pipe(s) following Step 14 (page 8) of Diamond Aircraft Industries GmbH Work Instruction WI-OSB-42-122, Revision 2, dated June 24, 2016. (3) The replacement required by paragraph (f)(2) of this AD does not terminate the repetitive inspections required by paragraph (f)(1) of this AD when a DAI part number  (P/N) D60-9078-06-01_01 or Technify P/N 52-7810-H0014 01 engine exhaust pipe is installed.

The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, Standards Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Mike Kiesov, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4144; fax: (816) 329-4090; email: mike.kiesov@faa.gov. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (3) Reporting Requirements: For any reporting requirement in this AD, a federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.

This AD was prompted by cracks in the affected engine exhaust pipes, which could cause failure of the propeller regulating valve because of hot exhaust gases coming from the fractured pipes. We are issuing this AD to prevent an uncommanded engine in-flight shutdown or overheat damage, which could result in a forced landing, consequent damage, and occupant injury.

None.