Santiago-based LATAM has added a fifth leased aircraft—a Boeing 747-400—to fill in for grounded 787s as they are taken out of service for newly mandated Rolls-Royce Trent 1000 inspections.

The 747-400 joins four Airbus A330-200s flying for LATAM—all of them on short-term leases from Spain’s Wamos Air. LATAM is using them to operate several long-range routes, including Guayaquil-Madrid, Santiago-Bogotá, and Guayaquil-New York, in place of 787s.

LATAM is one of about 15 operators dealing with reliability issues on their 787 Trent 1000 Package C engines. The carrier, the first in the Americas to operate the Boeing widebody twin, has been hit harder than most.

A LATAM spokesman confirms that about a quarter of the carrier’s 24-aircraft 787 fleet is out of service, and it could get worse, depending on the outcome of the latest inspections.

“The carrier is taking additional measures to maintain its schedules, including the reassignment of aircraft on selected long-haul routes and the lease of an additional Boeing 747 from Wamos Air,” the spokesperson said. “Further details about service changes will be communicated to passengers in due course.”

LATAM finalized the 747-400 lease as European and US regulators were preparing to order the latest round of inspections and operational restrictions on Trent 1000 Package C-powered 787s. Affected aircraft also face extended operations (ETOPS) restrictions that limit how far they can fly from the nearest suitable airport.

The latest inspections and ETOPS limits are tied specifically to findings of cracked intermediate pressure compressor (IPC) stage two blades, leading to unscheduled engine removals. The issue, one of several that have plagued the Trent 1000 and disrupted airline operations in the last two years, has not been linked to any inflight shutdowns.

The restrictions are expected to hit some carriers harder than others, with airlines that fly long transoceanic flights facing the biggest challenges. Among those that expect the newest restrictions to affect operations are Air New Zealand and Scoot. LATAM is one of several carriers that leased aircraft fill in for grounded 787s before the latest issues emerged, and the number of leased aircraft filling in for grounded 787s is expected to increase.

One reason for the lease activity: Even operators unaffected by the ETOPS limitations are likely to face disruptions if, as expected, many engines fail the latest mandated checks. Engines with cracked blades must be removed and repaired, and Rolls-Royce is struggling to keep up with demand for parts and MRO capacity.

The new Package C mandates affect about 200 787s. Industry estimates suggest the new inspections and expected groundings could leave about 25% of the affected fleet out of service, including aircraft already down because of the ongoing reliability issues.

Rolls-Royce is designing new IPC parts to eliminate the issue, but they are not expected to be available until early 2019. In the meantime, the OEM is ramping up MRO capacity and stockpiling airworthy blades, including from out-of-service engines. It is also analyzing the failure modes to demonstrate that cracked blades will not lead to failures—a move that could see the ETOPS restrictions eased.

The new Trent 1000 TEN engine, which has only about 25% parts commonality with the Trent 1000 Package C, is not affected by the IPC issues.

(Sean Broderick - Aviation Week / ATWOnline News)