(Bloomberg) -- On a historic day of four planned space launches, Lockheed Martin Corp. is betting that the first of its long-delayed, next-generation Global Positioning System satellites can do its job even though congressional investigators say it has suspect capacitors that could undermine its mission.

A GPS-III satellite scheduled to be sent into orbit by Elon Musk's SpaceX on Tuesday morning in Florida is the first of a new wave of spacecraft which promise greater accuracy and stronger signals to help guide everything from ride-sharing services to missiles.

But the satellite, launching four years late, contains about 600 suspect capacitors out of nearly 28,000 parts used on its navigation payload. The Air Force decided in 2016 not to replace them after the capacitors were discovered on the second and third satellites being built and pulled them out.

All sides agreed that the subcontractor at the time, Exelis Inc. and now Harris Corp. had failed to do required testing on the capacitors five years earlier, in 2011, with Lockheed saying it was responsible for maintaining oversight of its subcontractors. Despite the setback, the Air Force, Lockheed and Harris all expressed confidence that the satellite will operate as expected.

The Air Force decided that the risk in taking it apart and reassembling it "to remove and replace the capacitors was greater than the risk of launching the satellite 'as is,'" said Cristina Chaplain, director of space acquisition oversight for the independent Government Accountability Office, via email.

The $529 million satellite was already 28 months late at the time in 2016 when the service began investigating capacitor failures. But "rigorous" ground testing of the satellite gave the companies and the Air Force confidence they could go forward without opening up the satellite, Chaplain said.

Nevertheless, "by definition, this satellite has a greater level of risk built in," she added, saying "cost and schedule considerations also were at play, obviously," in the decision not to tamper with the first satellite.

The Air Force Space and Missile Systems Center said in an email that the satellite, which weighs 9,700 pounds when fueled, "has undergone more than 11,000 hours of testing without capacitor failures, giving further confidence" that it "will perform nominally."