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The UK Civil Aviation Authority (CAA) and the Federal Aviation Administration (FAA) have agreed to a revised version of the Maintenance Implementation Procedures for the approval and monitoring of maintenance and alteration or modification facilities.

The UK and US aviation regulators updated the arrangement to include a transition period for US-based organisations until 31 December 2024​.

This means both parties can continue to provide maintenance services and maintain aircraft parts for installation on UK-registered aircraft using a FAA/ European Union Aviation Safety Agency (EASA) dual release during the transition period.

The Maintenance Implementation Procedures address the approval and monitoring of maintenance facilities, enabling both countries to cooperate and provide technical support in evaluating and accepting each other's approved maintenance organisation systems.

The UK CAA and the FAA will also update the Maintenance Agreement Guidance (MAG), relating to the certification of Repair Stations/Approved Maintenance Organisations that perform maintenance and alterations of modifications on civil aeronautical products.

Both arrangements were first signed in 2020, following the UK’s exit from the European Union, under the existing Bilateral Safety Agreement from 1995.

An initial transition period of two years had been introduced in which the UK CAA continued to accept EASA maintenance releases from US-based organisations until a maintenance approval is obtained in the UK.

The updated arrangements were signed in the UK and US following the ongoing bilateral cooperation between the UK Civil Aviation Authority and the Federal Aviation Administration, working together to build and maintain close working relations and confidence in each other’s systems.

Notes to editors

  • The UK Civil Aviation Authority recommends that US-based organisations apply for and obtain a UK CAA approval when they renew their EASA Part 145 approval, but in any case prior to 31 December 2024. This will allow for FAA to perform one evaluation exercise to renew the EASA approval and issue the CAA approval​. Maintenance releases from organisations using the FAA/EASA agreement will not be acceptable for UK-registered aircraft after 31 December 2024.
  • The Special Conditions in the Maintenance Implementation Procedures (MIP) have also been revised to include new requirements for organisations based in the US. For UK-based organisation there is no change under the revised arrangements.
  • The Maintenance Agreement Guidance has been updated to reflect the changes in the MIP and to provide the processes for the FAA, UK CAA and US-based Repair Stations to follow to obtain UK Part 145 approval.
  • For more information, please see here.