Rolls May Have Known Of Trent Failure Risk

As the Australian Transport Safety Bureau investigation progresses into the Nov. 4 inflight uncontained failure of a Trent 900 on a Qantas Airbus A380, it has emerged that Rolls-Royce may have known about deficiencies well before the incident. Rolls, which has said very little publicly, revealed a week after the incident that a component failure in the engine caused an oil fire that led to “the release of the intermediate pressure turbine disc.” It says that it will address the issue through inspections and by “the replacement of the relevant module according to an agreed program.” However, Aviation Week has learned that 15 of the 16 engines of Lufthansa’s four Airbus A380s already incorporate an upgrade that addresses the risk of oil leakages. According to industry sources, the Lufthansa engines are equipped with new casings around a bearing that is strongly suspected as the source of the oil leak. Earlier versions of the Trent 900 did not have that casing. Three of the four Lufthansa A380s were delivered well before Nov. 4, and only one of the engines on D-AIMA (its first A380, which was delivered in May) does not comply with the latest standards and needs replacing. Qantas CEO Alan Joyce expects to have to replace up to 14 of the Trent 900 engines powering the airline’s six grounded A380s. Citing Rolls, Joyce says the total replacements for all operators could reach about 40 engines. Another hint that the problem may have been identified much earlier is that Rolls is pulling engines from A380s in final assembly to help Qantas in particular to replace earlier versions. Given that A380 engines spend a long period on wing before delivery, as aircraft must be ferried for cabin furnishing, it would suggest that the enhancements were introduced at least several months ago. It is not clear so far, however, why Rolls did not order the replacement of earlier versions on in-service aircraft. One industry official believes that the manufacturer seriously underestimated the extent of the problem.