Regulatory Change | EASA Airworthiness | May 2026 Published: May 15, 2026 | Last Updated: June 2026 | Source: EASA ED Decision 2026/003/R
Quick Summary
EASA published updated certification standards for normal-category aeroplanes — CS-23 Amendment 6 and AMC & GM to CS-23 Issue 5 — on May 5, 2026.
The update incorporates revised ASTM International F44 consensus standards as acceptable means of compliance, improves harmonization with FAA certification practices, and delivers a new, improved online version via the eRules platform.
It applies to all manufacturers, design organizations, and type certificate holders in the normal-category segment.
Quick Facts
| Item | Details |
|---|---|
| Authority | EASA |
| Document | ED Decision 2026/003/R |
| Published | May 5, 2026 |
| Regulation Updated | CS-23 — Normal-Category Aeroplanes |
| New Version | CS-23 Amendment 6 / AMC & GM Issue 5 |
| Key Change | Updated ASTM International F44 consensus standards |
| FAA Harmonisation | Yes — explicit objective |
| Applies To | Manufacturers, DOAs, type certificate holders |
| Format Available | PDF, XML, online (eRules platform) |
What Changed
The May 2026 revision updates the Acceptable Means of Compliance (AMC) and Guidance Material (GM) to CS-23, moving from Issue 4 to Issue 5.
Key changes include:
- Updated ASTM F44 consensus standards incorporated into AMC1 to CS-23 — reflecting the latest methods for demonstrating compliance with normal-category certification requirements
- Improved FAA harmonization — reducing the need for certification review items (CRIs) and special conditions in parallel EU/US programs
- New eRules online publication with optimized navigation, permalinks for each rule article, improved filters, and mobile compatibility
- Machine-readable XML format added for integration with compliance management systems
The underlying CS-23 Amendment 6 structure is unchanged. The update targets the AMC and GM layer — the practical compliance guidance layer — not the core certification specifications themselves.
Why It Was Updated
EASA’s CS-23 framework is performance-based. It relies on ASTM International F44 committee consensus standards as its primary acceptable means of compliance.
ASTM F44 updates these standards regularly to reflect advances in:
- Materials and structural design
- Avionics and digital systems
- Electric and hybrid propulsion — increasingly relevant to the normal-category segment
- Software assurance and cybersecurity integration
When ASTM updates its standards, EASA must refresh its AMC/GM to keep the compliance pathway current. Without this, manufacturers face growing gaps between available technology and regulatory approval routes.
Who Is Affected
Aircraft Manufacturers and Type Certificate Applicants: Any manufacturer with an active CS-23 type certificate application must assess whether updated ASTM standards affect existing compliance demonstrations.
Design Organizations (DOAs): EU-approved design organizations must review their compliance matrices and update references from Issue 4 to Issue 5 where applicable.
Type Certificate Holders: Existing TC holders are not required to retrofit compliance — but should assess whether Issue 5 updates create opportunities to simplify ongoing CRI management.
National Aviation Authorities (EU Member State CAAs) Oversight teams must update audit frameworks to reflect Issue 5 guidance material.
MRO Organizations: Maintenance programs that reference AMC/GM to CS-23 should be reviewed for compatibility with updated guidance.
Compliance Timeline
| Milestone | Date |
|---|---|
| ED Decision 2026/003/R published | April 15, 2026 |
| CS-23 Amendment 6 / Issue 5 file replaced (eRules) | May 5, 2026 |
| Online publication (new eRules platform) | May 2026 |
| Applicable to ongoing certification programmes | Immediately |
Operational Impact
Reduced Certification Friction: Incorporating updated ASTM standards directly reduces the number of CRIs needed in parallel FAA/EASA certification programs. This cuts time and cost for manufacturers seeking bilateral approval.
Electric and Hybrid Airplane Programs: Updated ASTM F44 standards increasingly reflect compliance pathways for electric propulsion. For manufacturers working on certified electric or hybrid normal-category aircraft, Issue 5 may materially expand available compliance routes.
eRules Platform Improvement: The new online version delivers permalinks to specific rule articles — a practical improvement that reduces the risk of compliance teams referencing superseded guidance. XML format supports direct integration into compliance management platforms.
Industry Response
EASA framed the update as part of its ongoing commitment to maintaining state-of-the-art certification pathways and supporting global harmonization.
The ASTM F44 process is a joint EU-US standards development activity — making its incorporation into CS-23 a direct expression of the bilateral aviation safety agreement between EASA and the FAA.
No adverse industry comment has been published. The update is consistent with EASA’s established regulatory update cycle for CS-23.
Official Sources
- EASA — ED Decision 2026/003/R
- EASA — CS-23 Amendment 6 / AMC & GM Issue 5 (eRules)
- EASA — CS-23 Document Library
Action Steps
Manufacturers, design organizations, and certification teams should:
- Review Issue 5 AMC/GM against current compliance matrices for active programs
- Identify which ASTM F44 standards have been revised and assess impact on existing CRIs
- Update internal compliance documentation to reference AMC & GM Issue 5
- CAAs: update oversight audit checklists to reflect new guidance material
- MRO quality teams: check maintenance program references for CS-23 AMC/GM applicability
Frequently Asked Questions
What is EASA CS-23? CS-23 is EASA’s Certification Specifications for Normal-Category Aeroplanes — the primary airworthiness standard for certifying small fixed-wing aircraft up to 19 seats and 8,618 kg MTOW in the EU.
What is the difference between CS-23 and AMC & GM to CS-23? CS-23 sets the performance-based requirements. The AMC and GM provide acceptable means of demonstrating compliance. ASTM International consensus standards sit within the AMC layer as approved compliance tools.
Does Amendment 6 / Issue 5 require recertification of existing aircraft? No. The update applies prospectively to new certification applications and ongoing programs. Existing type certificates are not affected unless the holder voluntarily seeks to use updated AMC material.
What is the ASTM F44 committee? ASTM F44 is the American Society for Testing and Materials International committee that develops consensus standards for general aviation aircraft. Its standards are incorporated into both EASA CS-23 and FAA Part 23 as acceptable means of compliance — making them the primary tool for bilateral EU-US certification harmonization.
How does this affect FAA bilateral certification programs? By aligning CS-23 AMC/GM with the latest ASTM F44 standards — which also underpin FAA Part 23 compliance — the update reduces the number of certification review items needed for parallel FAA/EASA programs. This directly cuts cost and timeline for manufacturers with bilateral programmes.
Where can I access the updated CS-23 documentation? The CS-23 Amendment 6 / AMC & GM Issue 5 is available free of charge on the EASA eRules platform in PDF, XML, and online formats at easa.europa.eu.
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Editorial Note: This article is based on EASA’s official ED Decision 2026/003/R and the updated CS-23 eRules publication. Compliance implications for specific programs should be assessed by qualified certification engineers and legal advisors. Researched and reviewed using official EASA regulatory publications.