London - The Boeing 787 operators are not only required to have their Trent 1000 engines inspected more frequently but also to accept a reduction in ETOPS limits. Several hundred Dreamliners are affected by new regulations from the leading regulators FAA and EASA.

Due to persistent quality problems in compressor blades, the European Aviation Safety Agency EASA issued an airworthiness directive on April 20. Thus, all Trent 1000 Package C engines with more than 2000 cycles must be inspected every 200 cycles.

In addition, the Standard Package C borescope examinations must be carried out more frequently than usual. The shortened maintenance intervals affect around 400 engines.

The problems also have consequences for the ETOPS approval of the Trent 1000 engines. The US aviation authority FAA also issued an airworthiness directive last week for the Boeing 787-8 and 787-9 with Trent 1000-A2, -AE2, -C2, -CE2, -D2, -E2, -G2, -H2, -J2, -K2 and -L2 series.

ETOPS (extended-range, twin-engine operations) indicates the maximum flight time to the nearest airport in the event of an engine failure. The engine variants mentioned are downgraded from 330 minutes to 140 minutes.

The blades of the medium-pressure compressor have a shorter life than expected. They can break under high thrust, at certain temperatures and high altitude conditions, resulting in engine failure.