Five aviation authorities are trying to reduce duplicated AAM certification work through a joint roadmap. The objective is coordinated validation and convergence where practical—not automatic mutual recognition or a single global eVTOL rulebook.
5 — aviation authorities in the NAA Network (FAA, UK CAA, Transport Canada, CASA, CAA NZ) April 2025 — Roadmap for AAM Aircraft Type Certification, Edition 1.0 published January 2027 — target date for eliminating FAA/UK CAA airworthiness-requirement differences ~60% / ~40% — average existing-CFR vs. new-AAM-specific criteria split across 5 sampled US applications (DOT OIG, 2023 data)
The five-authority roadmap aims to reduce duplicated AAM compliance work through coordinated validation. It does not make a type certificate automatically valid across all five jurisdictions or replace existing bilateral responsibilities.
Concrete validation practice: which compliance findings are accepted across authorities, which differences trigger additional substantiation, and whether applicants actually avoid duplicated tests.
In April 2025, the FAA, UK CAA, Transport Canada, Australia's CASA and New Zealand's CAA published a joint Roadmap for Advanced Air Mobility Aircraft Type Certification. The practical problem is validation: once one authority certifies an aircraft, how much of that compliance work can another authority rely on rather than repeat?
A validating authority can rely on findings made by the authority that issued the original type certificate, subject to bilateral arrangements and identified regulatory differences. The NAA Network roadmap aims to make that reliance more predictable and coordinated for AAM aircraft.
It does not create automatic recognition. Each authority retains its legal responsibilities, and existing bilateral agreements still govern formal acceptance. “Portable certification” is therefore shorthand for reducing duplicated substantiation, not a certificate that is automatically valid in five countries.
The roadmap describes work to identify differences in airworthiness requirements, coordinate standards activity and develop more efficient validation. For manufacturers, the potential benefit is substantial: common compliance evidence can be prepared with multiple validating authorities in mind rather than repeatedly reformatted or regenerated after the primary certification campaign.
There is a technical limit to harmonization. Authorities can share safety objectives while expressing requirements differently or accepting different means of compliance. The useful outcome may therefore be a well-defined crosswalk rather than identical regulatory text.
Cross-border reuse of compliance findings requires authorities to exchange enough information to understand what was approved and how. Some means-of-compliance material contains applicant proprietary data, so information-sharing arrangements have to protect intellectual property while preserving regulatory confidence.
The roadmap includes forward work and milestones, including efforts to address identified FAA/UK CAA differences. Those dates should be reported as authority targets. A missed publication or working-group milestone does not by itself establish that the broader harmonization effort has failed, just as an announced target does not prove convergence has been achieved.
As of the public material underlying this article, the framework remains largely prospective because the first generation of piloted AAM aircraft is still moving through type certification. The evidence to watch is concrete validation practice: which findings are accepted, which differences trigger additional work, and whether applicants actually avoid duplicated tests.
This article is regulatory analysis, not a forecast of any manufacturer's certification date.
