AD 2017-11-10 Airworthiness Directives; Lycoming Engines Reciprocating Engines

Makes named: lycoming. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to all Lycoming TIO-540-AJ1A reciprocating engines.

Comply with this AD within the compliance times specified, unless already done.

(1) For all engines, perform an initial exhaust system inspection within 10 hours time in service (TIS) after the effective date of this AD as follows: (i) Use the Required Action, paragraph 1. of Lycoming Engines Mandatory Service Bulletin (MSB) No. 627C, dated November 17, 2016, to do the inspection. (ii) For any part that fails the inspection required by paragraph (g)(1)(i) of this AD, before further flight, replace the failed part with a part eligible for installation. (iii) Use the Required Action, paragraph 3. of Lycoming MSB No. 627C, dated November 17, 2016, to submit a survey to Lycoming Engines within 10 days of performing the inspection. (2) For all engines, perform an initial torque check of the exhaust system flange nuts within 10 hours TIS after the effective date of this AD, or within 100 hours TIS after the last exhaust system maintenance (ESM), whichever occurs later, as follows: (i) Use the Required Action, paragraph 2. of Lycoming Engines MSB No. 627C, dated November 17, 2016 to torque check the flange nuts. (ii) For any part that fails the check required by paragraph (g)(2)(i) of this AD, before further flight, replace the failed part with a part eligible for installation. (iii) Use the Required Action, paragraph 3. of Lycoming MSB No. 627C, dated November 17, 2016, to submit a survey to Lycoming Engines within 10 days of performing the check. (3) For all engines with 1,000 hours TIS or less since the last ESM: (i) Repeat the actions required by paragraphs (g)(1)(i) through (iii) of this AD inclusive, every 25 hours TIS since the last ESM, or exhaust system inspection, whichever occurs later. (ii) Repeat the actions required by paragraphs (g)(2)(i) through (iii) of this AD inclusive, every 100 hours TIS after the last ESM, or torque check of the exhaust system flange nuts, whichever occurs later. (4) For all engines with more than 1,000 hours TIS since the last ESM: (i) Repeat the actions required by paragraphs (g)(1)(i) through (iii) of this AD inclusive, every 50 hours TIS since the last ESM, or exhaust system inspection, whichever occurs later. (ii) Repeat the actions required by paragraphs (g)(2)(i) through (iii) of this AD inclusive, every 100 hours TIS since the last ESM, or torque check of the exhaust system flange nuts, whichever occurs later.

This AD was prompted by several reports of engine exhaust leaks. We are issuing this AD to prevent engine exhaust leaks, which could lead to uncontrolled engine fire, harmful exhaust gases entering the cabin resulting in crew incapacitation, and damage to the airplane.

None.