Boeing Says New 787 Issue Affects Vertical Fins

Boeing 787 family
Credit: Boeing

Boeing confirmed that it uncovered a manufacturing problem with 787 vertical fins—the fourth production-quality issue linked to the widebody twinjet program in recent weeks.

The newest issue, like two others, involves non-conforming shims, or spacers used to fill gaps and ensure structures meet tolerances specified in their designs. Boeing said it discovered the issue in late 2019.

“The issue has been contained for all airplanes in production,” Boeing said. “We are working with the FAA to finalize guidance for the in-service fleet. Our expectation is that this will require a one-time inspection during regularly scheduled maintenance.”

The vertical fin issue was first reported by Seattle, Washington’s KOMO Newsradio. The news comes on the heels of Boeing acknowledging three other production issues with its 787s: two involving fuselage barrels and one involving horizontal stabilizers. One fuselage issue and the stabilizer issue also involve improper shimming. The other fuselage issue relates to smoothness of composite skin on the underside of the structure.

None of the four issues on its own poses an immediate safety-of-flight issue. But Boeing determined the two fuselage issues combined in the same location render affected aircraft unairworthy because their load-bearing capabilities are compromised. 

Instances of the two fuselage issues in the same location—where two rear sections join—have been found on eight in-service aircraft, which Boeing recommended be grounded for immediate inspections.

Boeing said it informed FAA of each issue when it was discovered. Boeing plans to order fleet-wide inspections to determine how many aircraft are affected by at least one of the four issues and will determine what actions are necessary.

Sean Broderick

Senior Air Transport & Safety Editor Sean Broderick covers aviation safety, MRO, and the airline business from Aviation Week Network's Washington, D.C. office.