• Frank Kendall, the Air Force Secretary, hit back on Elon Musk's comments slamming the F-35.
• While Kendall said he respects the billionaire, he said Musk is "not a warfighter."
• Musk has trashed the F-35 as obsolete compared to drones, but Kendall said that reality is decades away.

Air Force Secretary Frank Kendall said Elon Musk should learn more about air combat tech before publicly slamming crewed fighter jets as obsolete.

"I have a lot of respect for Elon Musk as an engineer," Kendall said on Thursday at the Mitchell Institute for Aerospace Studies.

"He's not a warfighter, and he needs to learn a little bit more about the business, I think, before he makes such grand announcements as he did," Kendall said.

Musk recently drew public attention for posting on X that crewed fighters, such as the F-35 Lightning II Joint Strike Fighter, were inefficient compared to drones and have a "shit design."

Calling the makers of the F-35 "idiots," Musk posted videos of drone swarms and wrote that crewed fighters would be shot down easily by modern surface-to-air missile defenses and enemy drones.

Kendall, who oversees the US Air Force's budget, said Musk's vision of drone superiority is many years away.

"It's provocative, it's interesting," he said of Musk's statements. "I can imagine at some point; I don't think it's centuries, by the way; I think it's more like decades when something like he imagines can occur."

"But we're not there," Kendall added. "And it's going to be a little while before we get there."

Musk did not respond to a request for comment sent outside regular business hours by Business Insider.

Kendall said he pushed the Air Force on a "key decision" to field drones that work in tandem with crewed fighters.

Still, he added the US may eventually reduce its planned purchases of the F-35, a fifth-generation fighter that Lockheed Martin manufactures, depending on how quickly other tech advances.

"Our inventory objective for the F-35 is 1,700 and some. I don't know what we'll end up buying, and nobody can predict that right now," the secretary said.

But he also doesn't think the F-35 will be replaced anytime soon, and said the US is still buying more of the aircraft for now and in the near future.

"It is dominant over fourth-generation aircraft. Period. And in a very, very serious way. It's not even close. And there's no alternative to that in the near term," he said.

The US has been looking into a sixth-generation fighter, also known as the next-generation air dominance program, that will focus on crewed jets that work collaboratively with drones.

Kendall said that if the NGAD program continues, it will still take years to produce that fighter in quantity, and it will be initially "very expensive" to manufacture.

It's unclear how Musk's views on the F-35 and drones may materially affect US defense spending. The billionaire has been made the cohead of a new Department of Government Efficiency, which aims to reduce what it sees as excess federal expenses.

Musk is in President-elect Donald Trump's close orbit and showed this week that he can wield considerable influence in Congress when Republican lawmakers followed his lead on trashing a bipartisan bill that sought to avoid a government shutdown.

Meanwhile, Kendall is expected to step down as Air Force Secretary when President Joe Biden, who appointed him, leaves office in January. The secretary expressed a desire in September to remain in his post as the Trump administration takes over.