The U.S. Air Force has pulled more than 100 C-130 Hercules aircraft that were constructed at Lockheed Martin’s Marietta plant after “atypical” cracks were found on one unit’s wing joint.
On Wednesday, Gen. Maryanne Miller, Air Mobility Command commander, ordered the temporary removal of 123 of 450 Total Force C-130 Hercules from service after cracks were found on one aircraft’s lower center wing joint or “rainbow fitting” during scheduled maintenance.
The discovery led to the ordering of inspections on affected C-130H and J-model aircraft that had not received extended service life center wing boxes and have more than 15,000 equivalent flight hours. Removal of the affected aircraft for inspections is not expected to impact overseas contingency operations, according to an Air Mobility Command Public Affairs news release.
“The Air Force takes the safety of its airmen and aircraft very seriously and is working diligently to identify and repair affected aircraft as soon as possible,” Air Mobility Command said in its release Wednesday.
The C-130 began production in 1954 and is the longest continuously running military production line in history, with every production C-130 having been built in Marietta. The company has built 2,600 such aircraft in four major models, including the C-130J, which is the current model.
“We are aware of this issue and are supporting the U.S. Air Force in identifying the root cause, which was discovered during a routine scheduled inspection. We also are advising similar inspections and support for customers who operate legacy C-130s/L-100s and C-130J aircraft,” the company said in a statement Friday,
More than 425 C-130Js have been delivered by Lockheed Martin as of Aug. 1, with the aircraft operated in 20 countries for a total of 2 million flight hours, according to a fact sheet provided by the company.
All new production C-130Js have the enhanced service life wing, which has been part of the production line since 2009; a smaller number of early C-130Js did not have the ESL wing as part of the aircraft upon initial production, the company added. The Air Force has installed ESL wings on some of these aircraft.
Through Thursday, the first full day of inspections, 23 of the pulled C-130s had been inspected and put back and service, according to Alexandra Soika of Air Mobility Command Public Affairs. An updated number through Friday afternoon was not made available by press time.
It is unknown how long it will take to inspect all the pulled aircraft.
“The inspections are occurring at the locations the aircraft were at when the (order) was issued and the overall timeline for completion is dependent on the capacity to inspect at those locations,” Soika said. “Operational requirements are also a consideration in this timeline.”
If cracking is found on an aircraft’s rainbow fitting during the eight-hour-long inspection process, a replacement of the damaged fitting will be required. Inspected aircraft that are determined to have no cracking will be immediately returned to service.