ToR RMT.0180

Turbine engine endurance and initial maintenance inspection testing, and piston engine time between overhauls substantiation

This Rulemaking Task (RMT) addresses the following issues:

  1. The turbine engine endurance test conditions that are required by the Certification Spefications for Engines (CS-E) are very hard, if not impossible, to achieve with modern engines.
  2. An initial maintenance inspection (IMI) test for turbine engines is required by the Federal Aviation Administration (FAA) regulations for many years, but not by the European (Joint Aviation Authorities (JAA) and European Union Aviation Safety Agency (EASA)) certification specifications (CSs).
  3. CS-E does not contain a specification for applicants to demonstrate the time between overhauls (TBO) interval. A safety recommendation on this matter was addressed to EASA.

The specific objective of this RMT is to modernise the engine certification test requirements to:

  • upgrade the turbine engine endurance test specifications to take into account modern engine design characteristics;
  • improve the level of confidence in the robustness of turbine engine designs prior to entry into service, as well as, in some cases, the definition of initial maintenance inspection (IMI) intervals;
  • ensure that EASA exercises oversight of the IMI tests and benefits from the resulting knowledge;
  • ensure the robust and harmonised substantiation of the TBO and of the maintenance programmes for piston engines; and
  • ensure the greatest possible harmonisation with the related FAA regulations and certification policies.