Lockheed, the Pentagon’s No. 1 contractor, is developing and building three variants of the new F-35 fighter for the U.S. Air Force, Navy and Marine Corps and eight foreign countries that are helping to fund its development -- Britain, Australia, Canada, Norway, Denmark, Italy, the Netherlands and Turkey.

Lockheed officials say the program is making progress, but lawmakers, like the Pentagon, are unconvinced.

The Pentagon’s director of testing and evaluation insists that more testing is needed before the Air Force and Marines start training pilots.

Pentagon spokeswoman Cheryl Irwin declined comment on the closed-door meeting, except to say that it was aimed at providing a status update and no major decisions were made.

The Pentagon’s F-35 program office also declined comment, but said officials were keeping a close watch on the program.

“All the technical issues are known and engineering solutions are either in work or being developed to deliver the F-35 to the warfighter,” said Joe DellaVedova, program spokesman.

The Marine Corps’ Amos said the F-35 program was making progress, and he did not expect huge new problems like the bulkhead cracks that had cropped up in recent years.

The Pentagon’s Defense Contracts Management Agency also gave an update on its work monitoring Lockheed’s Earned Value Management System after announcing in June that it would withhold 5 percent of the price of the fifth lot of production planes due to continued shortcomings with the system.

“We’re not happy that they’re not certified. However, the data they provide is still useful for monitoring performance on the program,” DellaVedova said.