The Pentagon and the world's biggest arms-dealer are hitting back at criticisms of their $400 billion stealth jet, the F-35 Joint Strike Fighter.

On Tuesday, Lockheed Martin, and the military’s F-35 Joint Program Office (JPO) condemned two Daily Beast reports highlighting issues with the jet’s currently inoperable 25mm cannon and sensor package—while confirming many of those stories’ central assertions.

“I’d like to help clear the air on some nameless/sourceless/baseless reporting you may have seen over the holidays that focused on two issues—the F-35 gun and EOTS,” wrote Joint Program Office spokesman Joe DellaVedova, using an acronym for the jet’s electro-optical targeting system.

Despite the strong language, however, the neither the JPO nor Lockheed could dispute a single fact in either Daily Beast report. And despite the “sourceless” accusations, more than half-a-dozen high-ranking military officials spoke to The Daily Beast during the compilation of its recent stories.

(DellaVedova, it should be noted, did not respond to previous requests for comment on about the jet’s cannon, which The Daily Beast reported would not be ready for action until 2019.)

In his Jan. 7 letter, he wrote that “contrary to recent media misreporting,” the F-35’s 25mm gun system “will be delivered” earlier, in 2017.

The statement is, at best, misleading. While the so-called “Block 3F” software that powers the gun will be in the hands of operational test pilots by 2017, everyday fighter pilots won’t get the new software until late 2018 at the very earliest, according to Air Force operational test and evaluation officials. The previous Daily Beast article specifically refers to the delivery of the Block 3F software to “frontline squadrons” flying “operational missions”—which is quite different from delivering the software to weapons testers.

According to Air Force operational testers, frontline squadrons won’t receive the new software until 2019. And that’s only if the software works properly, and is recommended for everyday use by frontline squadrons. Passing that test is not a foregone conclusion—the Air Force’s F-22 Raptor failed its operational evaluation the first couple of times. In fact, the F-35 cannot be cleared for full rate production until the end of operational testing—which runs through 2019, according to a Government Accountability Office report.

The JPO claims that the F-35 will be operational with the Block 3F software in 2018—one year earlier than the Air Force sources that spoke to the Daily Beast expect. “The U.S. Navy will attain IOC [initial operational capability] in 2018 with 3F software,” DellaVedova wrote. “This will provide all warfighters with multi-ship destruction of enemy air defense capability, advance air-to-ground and air-to-air capability and have full complement of internal and external ordnance—including use of the GAU-22 25mm gun.”

The JPO statement reflects its optimistic expectation that it will meet the Navy’s “objective” initial operational capability date of August 2018. Early Pentagon reports, delivered to Congress, weren’t nearly so sanguine.

“If the F-35 IMS Version 7 executes according to plan, Navy F-35C IOC criteria could be met between August 2018 (Objective) and February 2019 (Threshold),” reads one such report, delivered in June, 2013. “Should capability delivery experience additional changes, this estimate will be revised appropriately.”

And that’s a big if. Given that the F-35 program has suffered many delays and huge cost overruns over its long history, there is no reason that anyone should trust Lockheed Martin or the F-35 JPO, said Center for Defense Information analyst Winslow Wheeler, a long-time critic of the Joint Strike Fighter program.

“Why should anyone take anything they say seriously?” he asked.

“Lockheed Martin has a long history of misrepresenting facts,” Wheeler added. Further, “JPO and Lockheed Martin work hand in glove.”

The JPO statement also attacked a separate Daily Beast piece on the state of the F-35’s Lockheed Martin-built sensor system, known as EOTS. That article noted that the F-35 does not currently have the ability to down-link live video to ground troops,. In its attempt to discredit the story, the JPO inadvertently confirmed that fact. Nor does the jet have the ability to capture high-definition video, utilize an infra-red pointer. There isn’t even a solid plan in place to update the sensor—despite the fact that all of those missing capabilities are needed to support ground troops on the frontline.

“There are a range of potential upgrades and enhancements for EOTS that will be implemented by the Services and International Partners for inclusion in future Block upgrades,” DellaVedova said. “Some of the additional capabilities for consideration include items such as Higher Definition Video, longer range target detection and identification, Video Data Link, and Infrared (IR) Marker and Pointer.” (Emphasis mine.)

Of particular note—by DellaVedova’s own admission—these are potential upgrades. The program has not made a final selection on which upgrades will actually be included in future versions of the F-35.

In fact, according to F-35 program sources, the next software upgrades are not yet fully defined nor are they fully funded. Therefore, it is not possible for any F-35 schedule to include a video data link or infrared pointer at this point. Nor will the F-35 program know that it has the space to fit in an infrared point or high definition video capability until they actually have a plan in place to upgrade the new stealth fighter.

All of the missteps makes you wonder: if Lockheed and the Joint Strike Fighter’s program office can’t get a simple letter to reporters right, how successful will they be at building one of the most complex aircraft of all time?