Introduction

Following a major aircraft accident, attention normally focuses first on the airline. However, an aircraft accident is not necessarily caused exclusively by pilot error, adverse weather or operational negligence.

A defective aircraft design, manufacturing irregularity, faulty component, software problem, engine failure or inadequate warning by the manufacturer may cause the accident or materially increase the severity of its consequences.

This raises an important legal question:

Can passengers, survivors or the families of deceased passengers sue not only the airline but also Airbus, Boeing or another aircraft, engine or component manufacturer?

In principle, yes.

However, the legal basis of a claim against the manufacturer is fundamentally different from the claim against the airline.

International carrier liability is primarily governed by the Montreal Convention 1999, whereas claims against aircraft manufacturers will ordinarily arise under the applicable domestic law of product liability, negligence, strict liability or tort. Article 17 of the Montreal Convention principally establishes liability of the carrier for death or bodily injury caused by an accident taking place on board the aircraft or during embarking or disembarking operations.

This distinction is fundamental to international aviation litigation.

Airline Liability and Manufacturer Liability

Suppose an aircraft crashes because of a technical malfunction.

The accident may have resulted from:

a defective flight-control architecture;

an unreliable sensor;

an incorrectly manufactured component;

an engine component suffering premature failure;

a deficient fuel-system design;

or the manufacturer’s failure to communicate a known safety risk.

Two separate liability relationships may therefore arise.

The first is the contractual carriage relationship between the passenger and the airline. In international carriage, this relationship is substantially governed by the Montreal Convention. ICAO describes MC99 as the unified framework governing airline liability for passenger death and injury, delay, baggage and cargo in international carriage.

The second is the liability of a manufacturer for placing an allegedly defective product into circulation.

Airbus or Boeing is generally not the passenger’s “carrier” merely because it manufactured the aircraft. A manufacturer claim will therefore normally depend upon domestic product-liability or tort law rather than the carrier-liability provisions of MC99.

Design Defect

A design defect exists where the individual aircraft may have been manufactured exactly as intended, but the underlying design itself is alleged to be unreasonably unsafe under the governing legal standard.

Potential examples include inadequate crashworthiness of a fuel system, unsafe interaction between flight-control systems and sensor failures, insufficient redundancy, inadequate fire protection or another engineering architecture capable of creating an unreasonable accident risk.

The central question is therefore not:

“Was this aircraft manufactured according to its drawings?”

but:

“Was the approved design itself sufficiently safe?”

A useful aviation example can be found in the U.S. proceedings involving Riggs v. Airbus Helicopters. The plaintiffs asserted negligence and strict-liability claims against Airbus Helicopters and other defendants, alleging that the helicopter had been defectively designed because its fuel system was insufficiently crash-resistant. The Supreme Court docket demonstrates how an aviation manufacturer may directly become a defendant in a design-defect action.

Manufacturing Defect

A manufacturing defect is conceptually different.

Here, the design may be acceptable, but the specific aircraft or component deviated from the approved design or manufacturing specification.

Examples may include improper material composition, incorrect installation, defective bonding of composite structures, manufacturing contamination, incorrect torque or a component falling outside applicable production tolerances.

These cases often depend heavily upon production records, quality-control documentation, serial-number traceability, non-conformance reports and physical examination of the failed component.

The aviation certification structure itself distinguishes between design approval and production control. EASA type certification confirms that an aircraft type satisfies applicable safety and environmental requirements, while separate rules regulate approved production organisations.

Failure to Warn and Inadequate Instructions

Manufacturer liability is not necessarily confined to the physical aircraft.

A manufacturer may face allegations concerning inadequate:

warnings;

operating instructions;

maintenance procedures;

safety communications;

service bulletins;

or disclosure of previously identified technical risks.

The question may therefore become whether a manufacturer discovered a dangerous condition after entry into service but failed to communicate or mitigate that risk appropriately.

Modern continuing-airworthiness systems involve continuing interaction between aircraft design approval holders and operators. The FAA has expressly emphasized shared responsibilities concerning safety issues affecting an existing fleet and the importance of effective communication of safety information between design approval holders and operators.

Does FAA or EASA Certification Immunize a Manufacturer?

No automatic rule of that kind exists.

An FAA or EASA type certificate is highly important evidence of regulatory compliance. EASA explains that type certification confirms that the aircraft type satisfies the applicable EU safety and environmental requirements. FAA certification similarly assesses conformity with applicable airworthiness requirements.

However, regulatory compliance and civil liability are separate concepts.

Certification may constitute a powerful defence, but product-liability litigation may still examine issues such as information available to the manufacturer, known accident history, alternative designs, subsequent modifications and whether relevant risks were foreseeable.

U.S. aviation litigation has repeatedly considered the interaction between FAA regulation and state-law product claims. Proceedings involving Airbus Helicopters, for example, have addressed the manufacturer’s regulatory relationship with the FAA while simultaneously involving private-law allegations of defective design.

Potential Defendants Beyond Airbus or Boeing

A modern commercial aircraft is an integrated system composed of thousands of components.

Consequently, the manufacturer of the airframe may not always be the party primarily responsible for a technical failure.

Depending upon the accident, potential defendants may include the:

aircraft manufacturer;

engine manufacturer;

avionics manufacturer;

sensor or component manufacturer;

maintenance organisation;

MRO provider;

airline;

aircraft owner;

lessor;

or other operational actors.

Determining the correct defendant therefore requires a technical reconstruction of the causal chain.

Can the Airline and Manufacturer Both Be Liable?

Yes.

Aircraft accidents may result from several concurrent causes.

A component may have had a defective design while the airline also failed to comply with a maintenance requirement. A pilot may have responded incorrectly to an emergency, while inadequate cockpit warnings or deficient system architecture contributed to that response.

Manufacturer fault and operator negligence may therefore coexist.

Allocation of liability will depend upon the governing rules concerning comparative fault, contribution, joint liability and recourse.

A passenger’s claim against the airline under MC99 therefore does not necessarily eliminate a separate product-liability action against an aircraft manufacturer.

Turkish Law and Product Liability

Where Turkish substantive law is applicable, general tort principles and relevant product-liability rules must be examined.

Türkiye’s Product Safety and Technical Regulations Law No. 7223 forms an important part of the Turkish product-safety framework, and the Ministry of Trade identifies product-liability compensation among the significant mechanisms introduced by the legislation. The precise application of Law No. 7223 to aircraft and aviation products must nevertheless be assessed together with applicable sector-specific aviation regulation.

The conflict-of-laws question is particularly significant.

Article 36 of Turkish Private International Law Act No. 5718 establishes a specific rule concerning non-contractual liability arising from manufactured products. Subject to the statutory requirements, the injured party may choose between specified connecting laws, including the law of the habitual residence or place of business of the person causing the damage and the law of the country where the product was acquired.

Accordingly, Turkish nationality of a passenger does not by itself resolve the applicable-law issue.

International jurisdiction and applicable law must be analysed separately.

European Product Liability and Airbus

For claims connected with Airbus, the European product-liability regime may become particularly important.

The European Union replaced its historic Product Liability Directive framework with Directive (EU) 2024/2853, introducing significant reforms concerning technologically complex products, disclosure of evidence and evidentiary presumptions relating to defectiveness and causation in specified circumstances.

Timing is important.

Member States have until 9 December 2026 to transpose the new Directive. Its new regime principally applies to products placed on the market or put into service from that date, while earlier products remain subject to the previous framework. As of August 2026, this transitional issue must therefore be considered carefully for existing aircraft fleets.

For aviation cases, the disclosure provisions may be particularly important because much of the technical engineering information relevant to a potential design defect will ordinarily be within the manufacturer’s control.

Product Liability Claims Against Boeing in the United States

Claims against Boeing may raise significant questions under U.S. product-liability law.

Product liability in the United States is substantially governed by state law and may involve theories such as:

strict liability, negligence, design defect, manufacturing defect and failure to warn.

Because aviation is extensively regulated at federal level, however, disputes may also involve questions of federal preemption.

FAA certification therefore plays an important role, but it should not automatically be assumed that certification eliminates every possible state-law product-liability claim. U.S. litigation has repeatedly addressed the relationship between federal certification requirements and civil claims against aviation manufacturers.

Forum selection may be equally important. Personal jurisdiction, applicable state law, federal removal, forum non conveniens, discovery and limitation or repose periods may fundamentally affect the viability of the case.

Accident Investigation Reports and Civil Liability

The official aviation accident report will normally be one of the most important documents following a crash.

It must nevertheless be understood correctly.

ICAO Annex 13 expressly states that the sole objective of aircraft accident and incident investigation is the prevention of future accidents and incidents, rather than the apportionment of blame or legal liability.

An investigation report therefore does not necessarily answer the ultimate civil-law question.

The absence of a statement saying “Boeing was legally liable” does not prevent a manufacturer claim.

Conversely, identification of a technical failure in a safety report does not automatically establish legal liability.

Separate expert and judicial assessment remains necessary.

Evidence in an Aircraft Product-Liability Case

Critical evidence may include:

• flight data recorder information;
• cockpit voice recordings;
• wreckage and failed components;
• aircraft maintenance records;
• airworthiness directives;
• service bulletins;
• type-certification documentation;
• engineering and design records;
• software versions;
• manufacturing records;
• quality-control documentation;
• prior similar failures;
• internal safety assessments; and
• communications between the manufacturer and operator.

Access to such evidence can differ substantially between jurisdictions. The enhanced disclosure and evidentiary mechanisms contained in the new EU Product Liability Directive are particularly relevant to technically complex disputes where the claimant may face substantial information asymmetry.

Limitation Periods: A Critical Distinction

The distinction between airline and manufacturer liability is particularly important in relation to time limits.

Claims against an international carrier under the Montreal Convention are subject to the Convention’s two-year period under Article 35. ICAO guidance emphasizes that court proceedings must be brought within that period and that negotiations alone do not necessarily preserve the claim.

A separate product-liability claim against Boeing, Airbus or a component manufacturer may, however, be subject to an entirely different limitation or statute-of-repose regime under the applicable domestic law.

It is therefore dangerous to assume that the same deadline applies to all potential defendants.

Conclusion: Can Airbus or Boeing Be Sued After an Aircraft Accident?

Yes.

Where credible technical evidence indicates that an accident was caused or materially contributed to by a design defect, manufacturing defect, inadequate warning or another defect attributable to the aircraft or component manufacturer, a product-liability claim against Airbus, Boeing or another manufacturer may be legally possible.

Such a claim must nevertheless be distinguished from the claim against the airline.

A major international aircraft accident may therefore involve three parallel liability layers:

Carrier liability under the Montreal Convention or applicable aviation law;

manufacturer liability under product-liability and tort law; and

third-party liability involving maintenance organisations, component manufacturers, MRO companies and other actors.

The ultimate question is not merely whether a mechanical or software failure occurred.

The decisive legal inquiry is:

Why did the failure occur; was the risk foreseeable at the design or manufacturing stage; did the manufacturer know or reasonably have to know about the risk; was a safer design reasonably available; were adequate warnings issued; and did the alleged defect have a legally sufficient causal connection with the crash or the severity of the resulting harm?

Those questions lie at the core of modern aircraft manufacturer liability litigation.