EVERETT — The Boeing Co. grounded an undisclosed number of KC-46 aerial-refueling tankers last week because tools and other items were found in airframes after they left the factory here.
Boeing confirmed the grounding, first reported by The Seattle Times, and said flights were expected to resume Thursday.
Years behind schedule, the company just recently began delivering the first of an expected 179 KC-46 tankers to the U.S. Air Force. The plane can refuel aircraft while airborne and can carry troops and cargo.
“KC-46 flights were temporarily paused at the Boeing Military Delivery Center this past week,” Boeing said in a written statement, referring to the delivery center at Boeing Field in Seattle. The company said it was working with the Defense Contract Management Agency “on a plan to resolve a foreign object debris issue.”
“Safety and quality are the highest priority at Boeing,” the company said. “We are working together with the USAF/DCMA and expect to resume flight operations to support training flights today. There is no change to the current tanker delivery plan.”
The Seattle Times quoted an internal memo from managers to employees in the Everett factory that cited foreign-object debris and “tool control” as the reason for the grounding. “We have USAF pilots here for flight training and they will not fly due to the FOD issues and the current confidence they have in our product that has been discovered throughout the aircraft,” the memo said, according to The Times.
Nicknamed Pegasus, the KC-46 is based on the commercial 767. The basic airframe is assembled in the Everett factory before being modified for military use at a separate facility at the south end of Paine Field. The planes then are flight-tested at Boeing Field.
Foreign object debris is anything that shouldn’t be there, whether it’s inside an airframe or on a runway. It’s known as FOD in the aviation business. FOD is a constant hazard in airplane factories, where hundreds of people using hundreds of tools assemble the most complicated mass-produced products in the world. Companies like Boeing typically have strict procedures intended to prevent FOD on the assembly line.
The tanker FOD problem arose only a month after the company delivered the first Pegasus tankers to the Air Force, an occasion marked by a ceremony at the Paine Field factory on Jan. 24. The KC-46 program was more than two years behind schedule, and Boeing was still working out some problems.
To date, Boeing has delivered six KC-46 tankers to the Air Force, spokesman Chick Ramey said Thursday. Four are at McConnell Air Force Base in Kansas and two are at Altus Air Force Base in Oklahoma. “We expect the next delivery to occur shortly,” Ramey said.