The U.S. Air Force has ordered its entire fleet of KC-135 tankers to be grounded for inspection over concerns that their tails could fall off mid-flight if not properly fixed.
The USAF ordered the inspections on Tuesday for a "non-conforming part in the vertical tail assembly." Flight operations are restricted until the roughly 30-minute inspection is complete.
Tuesday’s order follows a Friday directive for each KC-135 tanker to be inspected for non-conforming vertical terminal fitting pins, or tail pins.
Friday’s requirement is to take place over the next two weeks, while the more recent directive requires inspections prior to the next flight.
"We're taking this action out of an abundance of caution, after consulting with our engineering experts," Col. Michael Kovalchek, Senior Materiel Leader with the Air Force Life Cycle Management Center's Legacy Tanker Division, said in a statement. "We are working closely with Air Mobility Command and all operational users and anticipate all potentially affected aircraft will be inspected."
As of Sunday, 90 aircraft had been inspected, with some two dozen found to have non-confirming pins, the USAF said. Planes that have already been inspected and found with proper pins have returned to flying status.
According to a memo shared online last week, more than 200 KC-135 aircraft could be impacted by this issue.
Efforts to replace the Air Force’s KC-135 fleet, which first rolled off the assembly line in the 1950s, have been underway for at least two decades. The aerial tankers refuel Air Force bombers and fighters in flight, extending their potential mission range to hotspots around the globe.
