AD Details
My first post so hope this is as easy as it appears.
Interesting that the EAD issued on the Trent 900 is not engine serial number specific. If there is a new configuration out there that eliminates this problem then I would have expected the EAD to be written against specific ESN's and that the newer ESN's would not require inspection thus lessening the burden on these affected airlines.
Also for the question about oil scavenging, the Trent 900 like all large turbine engines employ scavenging. The most modern engines incorporate bearing compartment technology that results in very low, like 0.01 quarts per hour of consumption.