The Federal Aviation Administration plans to require airlines to inspect 787 forward-pressure bulkheads to address a concern involving gaps caused by manufacturing defects.
Boeing says the issue, which has been known for several years, does not affect the safety of 787s.
Also, in October 2024 the company addressed the problem by issuing an Alert Requirements Bulletin that recommends the inspections that the FAA now plans to mandate.
“The FAA has received reports indicating multiple non-conformances, including excessive gaps and pull-up, were found during the assembly and installation of the [forward-pressure bulkhead],” says the FAA in a notice of proposed rulemaking released on 12 March. “These conditions are caused by insufficient clamp-up and non-conformance to the manufacturing process requirements.”
It says the gaps were “found between the Y-chords and attach angles”. They “can allow foreign object debris to become trapped between the parts, and burrs to be present around the holes after drilling”.
If not addressed, the problem can “result in undetected fatigue cracks that can grow to weaken the primarily structure”, the proposed rule says.
The requirement affects 135 US-registered 787s – seemingly the entire US fleet. The FAA will accept comments about the proposal for 45 days.
Issues with 787 aft-pressure bulkheads have been known since at least 2021, when Boeing said it was slowing 787 production to address gaps in forward-pressure bulkheads that did not meet Boeing’s specifications for the widebody jet.
At the time, Boeing said it would first rectify the defects on jets it had produced but not yet delivered, and that it was working to determine if in-service 787s might also need the fixes.
In 2024, Boeing functional chief engineer of mechanical and structural engineering Steve Chisholm said the bulkhead issue “had to do with a sub-supplier to one of our suppliers, and how they assembled parts”.
Spirit AeroSystems supplies Boeing with 787 forward fuselage sections, which contains forward-pressure bulkheads.
The FAA’s proposal would require operators to complete an “external detailed inspection” of 787 forward-pressure bulkheads.
“An inspector will have to get to the backside of the forward-pressure bulkhead, they’ll have to pull back insulation blankets, and they do a visual inspection around the circumference of the bulkhead,” Chisholm said last year.
The forward-pressure bulkhead problem is among numerous 787 manufacturing quality issues that arose in recent years. Gaps that failed to meet specifications, including those between fuselage barrel sections, were among the highest-profile defects.
Boeing has insisted that the gap defects do not affect the safety of 787s, saying a wealth of data indicates that affected 787 structures will maintain long-term integrity.
