AD 2006-03-14 Airworthiness Directives; Rolls-Royce plc RB211 Trent 500 Series Turbofan Engines

This AD applies to Rolls-Royce plc (RR) RB211 Trent 553-61, 553A2-61, 556B-61, 556A2-61, 556-61, 556B2-61, 560-61, and 560A2-61 turbofan engines. These engines are installed on, but not limited to, Airbus A340-500 and A340-600 series airplanes.

You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done. Initial Inspection (f) Using section 3, Parts A and B of the Accomplishment Instructions of RR Alert Service Bulletin (ASB) RB.211-72-AE836, Revision 1, dated October 5, 2005, perform an initial inspection of the high pressure-and-intermediate-pressure (HP-IP) turbine bearing oil vent tubes and bearing chambers as follows: (1) For IP Turbine modules (05 modules) with 9,600 hours time-since-new (TSN) or 1,200 cycles-since-new (CSN) or more on the effective date of this AD, carry out the inspection within 2,400 hours time-in-service (TIS) or 300 cycles-in-service (CIS) from the effective date of this AD, whichever occurs first. (2) For 05 modules that are below 9,600 hours TSN or 1,200 CSN on the effective date of this AD, carry out the inspection prior to 12,000 hours TSN or 1,500 CSN, whichever occurs first,. Repetitive Inspections (g) Repeat the inspection at intervals not to exceed 12,000 hours time-since-previous-inspection (TSPI) or 1,500 cycles-since-previous-inspection (CSPI), whichever occurs first, if at the previous inspection, any of the following conditions were observed: (1) There was no carbon buildup of a visible thickness. (2) The cleaning tool, HU82105, could pass along the full length of the internal vent tube into the bearing chamber. (3) The 8 mm diameter borescope could pass along the full length of the internal vent tube into the bearing chamber. (h) Repeat the inspection at intervals not to exceed 1,600 hours TSPI or 400 CSPI, whichever occurs first, if, at the previous inspection, the carbon restriction prevented the 8 mm diameter flexible borescope from passing through the internal vent tube, but the 6 mm diameter borescope could pass along the full length of the internal vent tube into the bearing chamber. (i) Remove the engine within 10 CSPI, if the carbon restriction prevented the 6 mm diameter borescope from passing through the full length of the internal vent tubes. 05 Modules in the Shop (j) For 05 modules in the shop on the effective date of this AD, inspect the vent tube for carbon buildup of a visible thickness and repair the vent tube as necessary prior to further flight. Information regarding the inspection and repair of vent tubes for 05 modules in the shop can be found in section B. of RR ASB RB.211-72-AE836, Revision 1, dated October 5, 2005. Alternative Methods of

This AD results from a report of an RB211 Trent 700 series engine that experienced a disk shaft separation, overspeed of the IP turbine rotor, and multiple blade release of IP turbine blades. We are issuing this AD to prevent internal oil fires caused by coking and carbon buildup, that could result in uncontained engine failure and damage to the airplane.