FAA AD 2026-15-01: Airbus A330 ETOPS-180 Crew Oxygen Limitation — Four-Crew Operations Restricted

Quick Answer

What does FAA AD 2026-15-01 require for Airbus A330 ETOPS-180 operators?

FAA AD 2026-15-01, effective September 3, 2026, requires revising the AFM Supplement on certain A330-200 and A330-300 aircraft modified by STC ST04038NY to limit ETOPS-180 operations to three flightcrew members. A single-cylinder oxygen system was found to be insufficient for four crew members during ETOPS-180 depressurization scenarios.

Quick Compliance Summary

Regulatory bodyFederal Aviation Administration (FAA)
AD number2026-15-01 — Amendment 39-23413
DocketFAA-2026-3873
Aircraft affectedCertain Airbus A330-200 and A330-300 series aircraft modified by STC ST04038NY
IssueSingle-cylinder flightcrew oxygen system insufficient for ETOPS-180 with four crew members
Required actionRevise AFM Supplement to limit ETOPS-180 to three crew members. Correct minimum oxygen dispatch pressure
Compliance deadlineSeptember 3, 2026
ATA Code35 — Oxygen
SourceFederal Register Vol. 91, No. 145, July 30, 2026 — FR Doc 2026-15455

Who Should Read This

This update is directly relevant to:

  • Directors of Operations for A330 operators conducting ETOPS-180 operations
  • Continuing Airworthiness Managers (CAMs)
  • ETOPS program managers
  • Flight crew scheduling and rostering teams
  • Dispatch and Operational Control departments

This AD applies only to A330 aircraft modified by a specific Supplemental Type Certificate. Not all A330 operators are affected. Check your fleet’s STC status against the applicability below.

At a Glance

ItemDetails
AD Number2026-15-01
Amendment39-23413
DocketFAA-2026-3873
ATA Code35 — Oxygen
AircraftCertain A330-200 and A330-300 series
STC requirementModified by FAA STC ST04038NY
Effective DateSeptember 3, 2026
Required Action 1Limit ETOPS-180 to three flightcrew members
Required Action 2Correct minimum oxygen dispatch pressure in AFM-S
Originating authorityEASA (MCAI referenced in AD)

What Changed

The FAA published AD 2026-15-01 on July 30, 2026. It is effective September 3, 2026.

The AD was prompted by a finding that certain A330 aircraft modified by STC ST04038NY have a flightcrew oxygen system supplied by a single oxygen cylinder. That single cylinder does not provide sufficient oxygen under all circumstances for ETOPS-180 operations with four flightcrew members.

The issue is specific to the STC modification, not to the base A330 aircraft design.

Why It Matters

ETOPS-180 operations permit an aircraft to fly routes where it may be up to 180 minutes from a suitable diversion airport. At that distance, crew oxygen endurance is a critical safety calculation. The oxygen supply must sustain all flightcrew members for the maximum diversion time in a depressurization event.

A single oxygen cylinder that is sufficient for three crew members may not be sufficient for four. The mathematics of oxygen consumption scales linearly with crew count. A fourth crew member on an augmented long-haul operation tips the calculation past the available supply.

If an in-flight depressurization occurs during an ETOPS-180 operation with four crew members and insufficient oxygen, the crew’s ability to maintain consciousness and control the aircraft through the diversion is compromised.

This is a direct life-safety issue.

Who Is Affected

This AD applies to Airbus A330 aircraft certificated in any category that have been modified by FAA Supplemental Type Certificate ST04038NY.

FamilyVariants
A330-200-201, -202, -203, -223, -243
A330-300-301, -302, -303, -321, -322, -323, -341, -342, -343

If your aircraft has not been modified by STC ST04038NY, this AD does not apply. Check your aircraft’s STC status in your supplemental type certificate records.

Required Action

Action 1 — Limit ETOPS-180 to three flightcrew members.

Revise the existing Airplane Flight Manual Supplement (AFM-S) to prohibit ETOPS-180 operations with more than three flightcrew members on aircraft modified by STC ST04038NY.

This means any flight planned as ETOPS-180 on an affected aircraft must operate with three crew, not four. If a four-crew-augmented operation is planned, the route must be replanned to reduce the ETOPS diversion time to below 180 minutes, or the aircraft must be operated on a route that does not require ETOPS-180 authority.

Action 2 — Correct minimum oxygen dispatch pressure.

Revise the AFM-S to correct the minimum oxygen dispatch pressure information. The current pressure values in the AFM-S are incorrect for the installed configuration.

Both revisions must be completed before September 3, 2026.

Operational Impact

The impact on crew scheduling is the most significant operational consequence. Airlines operating ETOPS-180 routes with augmented four-crew operations on affected A330 aircraft must either:

  • Reduce to three-crew operations on those routes
  • Replan routes to avoid ETOPS-180 diversion thresholds
  • Operate a different (unaffected) aircraft type on those routes

For airlines with a small number of STC-modified A330 aircraft in a larger fleet, the operational impact may be contained by reassigning affected aircraft to non-ETOPS-180 routes. For airlines with a large proportion of modified aircraft, the impact on crew scheduling and route planning could be substantial.

The AFM-S revision itself is a documentation task — straightforward and low-cost. The operational consequences of the limitation are the real burden.

Key Dates

EventDate
NPRM publishedApril 29, 2026
FAA AD 2026-15-01 publishedJuly 30, 2026
AD effective dateSeptember 3, 2026

Source Documents

  • Federal Register Vol. 91, No. 145, July 30, 2026 — FR Doc 2026-15455
  • AD Docket: regulations.gov, Docket No. FAA-2026-3873
  • FAA contact: Joseph Catanzaro — Joseph.Catanzaro@faa.gov, 516-228-7366

FAQ

Does this apply to all A330 aircraft?

No. Only A330-200 and A330-300 series aircraft modified by FAA Supplemental Type Certificate ST04038NY are in scope. Unmodified A330 aircraft are not affected.

Can we still fly ETOPS-180 with three crew on affected aircraft?

Yes. The limitation applies only to four-crew operations. Three-crew ETOPS-180 remains permitted on affected aircraft after the AFM-S revision.

What is STC ST04038NY?

It is a specific Supplemental Type Certificate that modifies the flightcrew oxygen system. Check your aircraft’s supplemental type certificate records to determine if this STC has been installed.

Why is the oxygen supply insufficient for four crew members?

The STC configuration uses a single oxygen cylinder. That cylinder provides sufficient oxygen for three crew members for the full ETOPS-180 diversion time. A fourth crew member increases oxygen consumption beyond the single cylinder’s capacity under all depressurization scenarios.

What is the compliance cost?

The AFM-S revision itself is a minimal documentation task. The operational cost — reassigning affected aircraft away from four-crew ETOPS-180 routes — depends on each airline’s fleet composition and route network.

Related Reading


aviationregwatch.com publishes regulatory intelligence for aviation compliance professionals. This article is an informational summary, not legal or airworthiness advice. Consult your aircraft manufacturer, CAMO, or legal counsel for compliance decisions.

About the Author
Raju KP  ·  Founder & Principal Analyst, Aviation Reg Watch

Raju founded Aviation Reg Watch, an independent publication covering aviation regulation, airline policy, airport governance, safety oversight and industry developments. His goal is to explain complex aviation regulations and policy changes in a clear, balanced, and practical way for aviation professionals, investors, and informed readers.

He brings more than 30 years of professional experience across banking, financial journalism, and management consulting. During more than nine years with a Big Four global advisory firm, he supported aviation-sector clients on research and consulting assignments involving airlines, airports, and aviation policy. Earlier in his career, he worked as a financial journalist covering macroeconomic data, financial markets, and policy developments.