The Federal Aviation Administration (FAA) has issued a proposed airworthiness directive (AD) following a report from Boeing indicating that certain inspections of the Boeing 787 main landing gear (MLG) were not conducted during production. This oversight, attributed to human error, was discovered during the manufacturing process of four drag brace lower link assemblies of the MLG, where a required fluorescent penetrant inspection was omitted.

Due to a human error

The FAA, in its notice of proposed rulemaking (NPRM), detailed the situation where Boeing reported the inspection lapse. An investigation determined that the quality escape was due to human error isolated to a single technician. The potential risk of undetected cracks leading to a fracture in the drag brace lower lock link assembly was highlighted. Such a fracture could result in the collapse of the MLG, compromising the aircraft’s directional control on the ground, potentially leading to runway excursions or penetration of the wing box fuel tank.

The proposed directive is based on Boeing’s Alert Requirements Bulletin (RB) B787-81205-SB320048-00 RB Issue 001, issued on November 20, 2023. While the bulletin initially identified affected aircraft as line numbers (LN) 6 to 1168, the FAA extended the directive to include all Boeing 787-8, 787-9, and 787-10 aircraft. The rationale is that the affected drag brace lower lock link assemblies are rotable parts, which could be installed on other aircraft initially delivered with compliant assemblies, thus exposing them to the same risk.

Impact on U.S. Aircraft

The FAA estimates that 156 Boeing 787 aircraft in the United States will be affected by this directive. Data from ch-aviation indicates that Boeing has delivered 132 787s to U.S.-based operators. Brian West, Boeing’s Chief Financial Officer (CFO) and Executive Vice President of Finance, mentioned during the company’s Q2 earnings call on July 31 that Boeing still has 787s in its inventory, which are expected to be delivered as production performance improves.

Stakeholder Engagement and Final Rule

The FAA has opened the NPRM for comments from stakeholders until September 16. Following the review of comments, the regulator will publish the final rule AD. This directive follows a recent disclosure by Boeing in May, where it was revealed that an employee had falsified inspection records at the North Charleston, South Carolina facility. Despite this, Scott Stocker, Vice President and General Manager of the 787 program, assured that this misconduct did not pose an immediate safety issue.

According to Simple Flying, in response to the proposed directive, a Boeing spokesperson reiterated that the NPRM was issued after the November 2023 bulletin, and no in-service incidents have resulted from the flagged condition.