* Pentagon working with Lockheed to improve quality
* Company said rate to improve as program matures
* Senate committee had raised concerns
By Andrea Shalal-Esa
WASHINGTON, June 8 (Reuters) - The rate of scrap, rework and repair on production of Lockheed Martin Corp's F-35 fighter jet is currently around 16 percent, higher than on other military aircraft programs at similar stages of production, the Pentagon said on Friday.
Both the Pentagon's F-35 program office and Lockheed Martin Corp "recognize this is an area that needs improvement, and are working together to achieve world-class levels of quality," said
Navy Commander Kyra Hawn, a spokeswoman for the program office.
Hawn said the other military programs had scrap, rework and repair rates in the mid to high single digits when they reached a production level of 100 aircraft. The F-35 is nearing production of its 100th jet.
Lockheed spokesman Michael Rein said the company's scrap, rework and repair rate was "commensurate with historical programs at the same stage of production" and should continue to improve as the program continues to mature.
The Senate Armed Services Committee said this week it was troubled by the quality of production on the $396 billion F-35 Joint Strike Fighter program, but did not provide any details.
The committee questioned the overall quality of production on the program and cited a "potentially serious issue" with the plane's electronic warfare capability.
Questions over the quality of production of the F-35 will compound the mounting woes of the program, which has already been restructured three times to extend the development phase and slow production.
The quality concerns are being raised as a strike by 3,300 union workers at the company's Fort Worth, Texas, plant over pension and healthcare benefits is moving into an eighth week.
Lockheed has hired about 200 temporary workers to keep production of its F-35 and F-16 fighters on track at the plant.
Lockheed says the new workers are being carefully trained, but union officials have questioned whether the quality of production - already an issue - would be maintained by workers with less experience on the complex weapons system.
Lockheed is building the new radar-evading fighters for the U.S. military and eight foreign countries helping to fund its development: Britain, Norway, Canada, Denmark, the Netherlands, Turkey, Australia and Italy.
Japan and Israel have also ordered the fighters for their militaries. The U.S. government expects to finalize the sale with Japan this month.
Lockheed also will soon submit a proposal to sell the aircraft to South Korea, with Seoul officials due to visit the United States this summer for F-35 simulator flight testing and visits to various production, flight test and training sites.
The Senate committee noted in a report accompanying its fiscal 2013 budget bill that a potentially serious issue had been discovered with an aperture on the aircraft that was critical to its electronic warfare capability.
The committee said the full extent of the problem was not known, but it underscored the need for the Pentagon and Lockheed to "rigorously manage production quality," it said.
Sources familiar with the program said the issue centered on the placement of a sensor at the tip of the plane's wing and was a design matter and nothing to do with production quality.
They said the previous placement had reduced the sensitivity of a small part of the electronic warfare sensor, but affected only jets in the first three production batches and had already been resolved in jets now under production.
Retrofits would be done as needed, but only a small number of aircraft would be affected, the sources added.