Inspections to identify incorrectly made parts on fittings that connect Boeing 787 floor beams to the fuselage will be required for more than 40% of the in-service fleet within 48 months, a Boeing bulletin related to the issue shows.
The requirements bulletin (RB), issued in December 2023 and recently made public, forms the basis of a draft FAA directive issued May 17. Boeing developed the RB after learning that some 787-9 and -10 fittings supplied by Leonardo do not contain the specified material, Ti-6AI-4V, a grade 5 titanium alloy.
Boeing has flagged 468 aircraft for inspections, the RB revealed. All affected aircraft are 787-9s and -10s built from August 2016 through October 2020, an analysis of the affected line numbers shows. The affected population is 64% of the 731 787-9s and -10s delivered through April 30, and 42% of the 1,127 787s delivered.
The fittings flagged for inspections are installed at 16 positions, or body stations, where the floor meets the fuselage. The affected body stations, 1233 through 1593, are in fuselage section 46, aft of the wings.
Boeing publicly acknowledged the problem in October 2021, citing a notice from Leonardo, which manufactures 787 section 46, that some parts installed in the fuselage subassemblies do not conform with the manufacturer’s specifications. The Italian supplier said a vendor it contracted, Manufacturing Processes Specification S.r.l., made the parts in question. The 787-8 does not use the same parts.
The agency plans to adopt Boeing’s recommended deadline of 48 months for addressing the issue and reliance on x-ray fluorescence spectrometer inspection to determine if fittings comply with Boeing’s design. But input from 787 operator Air Canada suggests Boeing is developing an alternative inspection procedure to help identify problem parts.
“Boeing is working on eddy current inspection as a second method for identifying titanium material compositions and actively shared with the operators that it will be included in” an upcoming bulletin, Air Canada told the FAA in a formal comment on the draft rule. “The second inspection [method] is critical as it is more readily available in the industry,” the airline added.
Fittings identified as being made from the correct material require no further work. All other fittings must be replaced. Alternatively, operators can skip the inspections and elect to replace all fittings.
When fittings are swapped, related fastener holes must be inspected.
The FAA calculates that replacing every fitting on an affected airframe will require 530 labor hr.
“The extent of damage found during the inspection done when the fittings are replaced could vary significantly from airplane to airplane,” the agency said. “The FAA has no way of determining how much damage may be found on each airplane, the cost to repair damaged parts on each airplane, or the number of airplanes that may require repair.”
