FAA Orders Inspections of Fuel Tank Sealant on 60 US Boeing 787s Over Lightning Risk

WASHINGTON, D.C., 2 November 2026 – The US Federal Aviation Administration (FAA) has issued an airworthiness directive requiring airlines to inspect sealant inside the center wing fuel tank of certain Boeing 787 Dreamliners. The rule, AD 2026-22-05, was published in the Federal Register on Monday and takes effect on 7 December 2026.

It applies to some 787-8, 787-9 and 787-10 aircraft, as listed in a Boeing alert bulletin dated 5 November 2025. The FAA estimates that 60 US-registered jets are affected. AeroTime reported the directive on 3 November.

What went wrong in production

According to the directive, the FAA received a report that certain sealant installations within the center wing fuel tank did not get their required visual and adhesion inspections while the aircraft were being built. The sealant involved includes edge seals, fillet seals, seal caps and injection seals, the directive shows.

The FAA says the risk is that a defect could go unnoticed. If not addressed, it warns, the condition “could result in development of an ignition source within the fuel tank volume and a risk of a fuel tank explosion during a lightning strike event.” The directive does not report any lightning-related incident on a 787.

The rule covers only the aircraft where there is not enough evidence that the checks were done. The FAA says it has confirmed that the sealant inspections are now being carried out in production on 787s outside the scope of the directive.

What airlines must do

Operators must carry out a detailed inspection of the sealant in the left, right and center wing side-of-body areas, including the area between the side-of-body rib and rib 2, and test how well the sealant has stuck. Any defects must then be repaired. The work follows the timetable in Boeing’s bulletin, with the clock starting on the directive’s effective date.

The FAA estimates the inspection and adhesion test at 34 work-hours per aircraft, or $2,890 at $85 an hour, and $173,400 for the 60 US jets. It has no data to estimate the cost of any repairs. According to Boeing, some or all of the costs may be covered under warranty.

Changes after public comment

The FAA first proposed the rule on 24 February 2026 and took comments until 10 April. The Air Line Pilots Association, United Airlines and one individual supported it without changes. Boeing and American Airlines asked the FAA to let airlines repair sealant using existing Boeing procedures rather than seek separate approval for each repair.

The FAA agreed in part: sealant repairs that meet Boeing’s published airworthiness limitations for the fuel tank are now an accepted fix under the directive. It also clarified the inspection area for American and answered a question from the Foundation for Aviation Safety about whether the checks are now required in production.

What it means for passengers

Nothing changes for travelers. This is a routine maintenance order, not an emergency directive, and the affected 787s keep flying while airlines schedule the work. The FAA rule applies to US-registered aircraft; regulators in other countries decide for themselves whether to adopt FAA directives for the 787s they oversee.

Read how the three 787 versions compare in our 787-9 vs 787-10 guide, or see the full Boeing 787-9 review.

Read more

• Boeing 787-9 Dreamliner review: cabin, engines and safety
• Boeing 787-9 vs 787-10: size, seats and range
• Boeing 787-10 vs Airbus A350-900
• How dangerous is turbulence? What the data says

Sources: FAA, AD 2026-22-05, Federal Register (full text), 2 November 2026; FAA proposed rule, 24 February 2026; AeroTime, 3 November 2026.

Featured image: FlyingFuel graphic using a photo of American Airlines Boeing 787-9 N838AA on approach to Boston by 4300streetcar, CC BY 4.0, via Wikimedia Commons.