The k2p blog

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/list/2010-16-07?OpenDocument

The Federal Aviation Administration issued an AD concerning the RR Trent 900 engine recently:

ACTION: Final rule; request for comments.

SUMMARY: We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Wear, beyond Engine Manual limits, has been identified on the abutment faces of the splines on the Trent 900 Intermediate Pressure (IP) shaft rigid coupling on several engines during strip. The shaft to coupling spline interface provides the means of controlling the turbine axial setting and wear through of the splines would permit the IP turbine to move rearwards.

Rearward movement of the IP turbine would enable contact with static turbine components and would result in loss of engine performance with potential for in-flight shut down, oil migration and oil fire below the LP turbine discs prior to sufficient indication resulting in loss of LP turbine disc integrity.
We are issuing this AD to detect rearward movement of the IP turbine, which could result in loss of disc integrity, an uncontained failure of the engine, and damage to the airplane.

DATES: This AD becomes effective September 17, 2010.

Of course it is far too early to say if this has anything to do with the Trent 900 engine failures experienced by Singapore Airlines and Qantas on their A 380’s but the AD does talk about the possibility of an “uncontained failure of the engine”.

Tags: A 380, Airworthiness Directive, Federal Aviation Administration, Qantas, Singapore Airlines

This entry was posted on November 4, 2010 at 10:08 am and is filed under Aviation, Engineering, Technology. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.