AD NUMBER: 2011-11-03

MANUFACTURER: Various Aircraft Equipped With Rotax Aircraft Engines 912 A Series Engine
SUBJECT: Airworthiness Directive 2011-11-03

SUMMARY: This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

During a production process review, a deviation in hardening of certain Part Number (P/N) 944072 washers has been detected, which exceeds the hardness of the design specification.
The affected washers are part of the magneto ring flywheel hub installation and have been installed on a limited number of engines. No defective washers have been shipped as spare parts.

This condition, if not corrected, could lead to cracks in the washer, loosening of the magneto flywheel hub and consequent ignition failure, possibly resulting in damage to the engine, in-flight engine shutdown and forced landing, damage to the aeroplane and injury to occupants.

This AD requires actions that are intended to address the unsafe condition described in the MCAI.

FMI: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/BB37B2E14756DD1F862578A2004F2DC9?OpenDocument