WASHINGTON Nov 1 (Reuters) - The Pentagon halted shipments of Lockheed Martin Corp's F-35 fighter jets for 30 days this fall after it discovered corrosion around fasteners and a fix was devised, people familiar with the situation said.
During maintenance, the Air Force detected corrosion where the carbon fiber exterior panel is fastened to the airframe. A lack of protective coating at the fastening point that would have prevented corrosion was identified as the primary problem, the sources said.
The fastener issue on the current F-35 fleet is not affecting flights, nor is it a safety concern, the people said. Lockheed is investigating the extent of the corrosion issue across the fleet of more than 250 jets deployed to the U.S. military and its allies.
Production was not stopped and deliveries for the fighter jet recently resumed after the 30-day pause this fall, the people said on condition of anonymity because they were not authorized to speak about the matter publicly.
The delivery pause was not expected to derail the Pentagon's target of accepting 66 jets in 2017, the people said. Lockheed, the Maryland-based weapons maker, delivered 46 jets in 2016.
Representatives for Lockheed and the F-35 joint program office at the Pentagon could not immediately comment.
This is the latest of several production issues that have arisen in the 17-year history of the Pentagon's most expensive weapons program. In 2016, a fix for insulation problems in the fuel tanks and lines of the jets caused a slowdown in deliveries.
The F-35 business accounts for about a quarter of Lockheed's total revenue. During the third quarter, sales at Lockheed's aeronautics business increased 14 percent to $4.7 billion, led by higher sales of the F-35 highlighting the program's importance to Lockheed's profitability.
In February, the Pentagon agreed to a deal for the tenth batch of the fighter aircraft and agreed to pay below $95 million per jet for the first time, compared with $102 million in the previous purchase, the lowest price up until that point. Around that time, the Pentagon said the price of a jet could fall 16 percent to around $80 million in future purchases.
(Reporting by Mike Stone in Washington; Editing by Chris Sanders and Nick Zieminski)