The Pentagon is trying to paper over serious problems with the F-35 joint strike fighter aircraft that could endanger troops, according to an investigation released Wednesday by the Project On Government Oversight.

An oversight board looking at development of the high-tech fighter made by Lockheed Martin decided in June to downgrade 19 of the aircraft’s most severe deficiencies without a plan for fixes, the watchdog group found.

The moves could help speed up the F-35 program, the most expensive in Pentagon history, as it moves into a critical phase of development, said Dan Grazier, a military fellow at POGO and long-time program watcher.

“They want to be able to go up to Capitol Hill and say, ‘Nope, we don’t have any more Category 1 deficiencies,’” Grazier said.

Those types of deficiencies can lead to death and injury, loss of the aircraft or a halt to the F-35 production line. The 19 Category 1 deficiencies downgraded by the F-35 Deficiency Review Board on June 4 included an emergency alert system for when pilots eject and a system for bombing coordinates that could protect troops on the ground from friendly fire.

The issues were moved to Category II status, which can impede a military mission, according to board meeting minutes obtained by POGO. Overall, the Government Accountability Office found the F-35 has 111 of the most severe Category 1 problems and 855 deficiencies classified as Category II.

“This is not how the development process is supposed to work,” according to the watchdog’s investigation.

The Pentagon’s F-35 Joint Program Office and Lockheed Martin did not immediately comment on the POGO investigation.

The next big hurdle for the F-35 comes on Sept. 15, which is the deadline for initial test and evaluation of the aircraft. The tri-service fighters are billed as the most advanced in the world and are chock full of new military technology. The Air Force and Marine Corps variants are already in operational use. The Navy's version is expected to be deemed ready to deploy next year.

“We are obviously just three weeks away from that, so the big rush to kind of clear up these paperwork issues is to try to meet that deadline,” Grazier said. “Having these deficiencies, it actually increases the likelihood that the program will not pass IOT&E.”