EASA AD 26-114 — Engine – High Pressure Turbine Blades – Inspection

Summary

EASA Airworthiness Directive 26-114 is a proposed directive addressing inspection requirements for high pressure turbine (HPT) blades on Rolls-Royce Trent 1000 engines installed on Boeing 787 aircraft. It applies to specific Trent 1000 engine variants with serial numbers prior to ESN 11603 and focuses on detecting cracks in HPT blades part number KH64485. The directive updates inspection procedures and intervals to ensure continued airworthiness and safety.

What Changed

This proposed directive supersedes EASA AD 2025-0206R1 and introduces updated on-wing borescope inspection instructions from Rolls-Royce Alert Non-Modification Service Bulletin TRENT 1000 72-AK316 Revision 7. It refines inspection thresholds, removes previous life limits, and specifies follow-on inspection and replacement criteria based on crack size and location on the HPT blades. The directive also clarifies inspection requirements following engine in-flight shutdown events.

Why It Matters

The directive is critical for aviation professionals as it addresses a known unsafe condition that could lead to high pressure turbine blade failure and potential engine in-flight shutdown. Operators and maintenance organizations must adhere to the updated inspection intervals and criteria to detect blade deterioration early, thereby preventing engine failures and ensuring flight safety. Compliance with these requirements supports regulatory conformity and reduces operational risks.

What To Do

Operators of affected Trent 1000 engines must perform on-wing borescope inspections of HPT blades before exceeding specified flight cycle thresholds and continue inspections at intervals not exceeding 50 flight cycles. Inspections must also be conducted within 10 flight cycles following any engine in-flight shutdown. If cracks are detected, follow-on inspections or blade replacements must be completed within the specified compliance times based on crack severity. All actions must follow the instructions in Rolls-Royce Alert NMSB TRENT 1000 72-AK316 Revision 7.