WASHINGTON — With Secretary of Defense Jim Mattis issuing new guidance demanding readiness for tactical air assets increase in just one year, the Pentagon is openly acknowledging that older planes will have to be retired and cannibalized for parts to make it happen.

The department will also look to overhaul how it handles its supply chain, according to the department’s No. 2 official.

In a September memo, first reported by Defense News, Mattis ordered the Air Force, Navy and Marines to get the Pentagon’s fleets of F-16, F-18, F-22 and F-35 fighters to a minimum of 80 percent mission ready. That would represent a major jump in readiness over a short period of time, raising skepticism amongst analysts.

From a pure numbers-on-paper standpoint, the easiest way for getting readiness rates up on the fleet would involve retiring older, less ready aircraft — essentially increasing the percentage of good-to-go planes by reducing the overall size of the fleets.

Such a move may not be popular on the Hill, which routinely complains about the size of the military compared with previous eras. But it’s a logical step being endorsed by both Deputy Secretary of Defense Patrick Shanahan and Gen. Robert Neller, top officer in the Marine Corps.

“You gotta get rid of airplanes. At some point, you gotta get rid of the old ones,” Neller told reporters Wednesday at a Defense Writer’s Group event, when asked how he would hit that 80 percent mark.

Neller added that such a move has to be part of a broader spectrum of moves, including better quality parts from vendors, being more efficient with maintainers, and adjusting the flying hours for pilots to make sure the wings aren’t being worn off on jets.

“It’s not going to be a single thing, so we’ve got to do our part,” he added.

Speaking to reporters at the AUSA conference the same day, Shanahan seemed to zero in on the oldest Navy jets as ones that could be retired.

“Well, when you look at the size of the fleet of the F-18s, you got [F-18A models] out there, then you look at what it would take to restore them to a certain level of readiness, you might say it’s much easier just to retire those,” he said. “So, I mean, there’s a mix of answers.”

“It probably doesn’t make sense to generate a lot of activity to make something that is older more reliable, but when you think about the joint strike fighter and the hundreds of those that we’re going to take, 80 percent should be the minimum, OK? It shouldn’t be some aspirational goal, it should be the minimum.”

However, he pushed back at the idea that anyone will “game the system” to get those readiness percentages up.

Commercial practices

In the memo, Mattis specifically notes the commercial aviation industry is able to maintain higher readiness rates and directs the service to look that way for inspiration.

“I am confident in our department’s ability to generate additional capacity from our current aircraft inventory, alongside the commercial aviation industry’s sustainment of high availability rates,” Mattis wrote. “As we seek to achieve our goals, we can learn from industry’s benchmarks for measuring speed, cost and mission capability, as well as its best practices for implementing a sustainable, Department-wide system.”

Shanahan, who will be the overall leader of the readiness rate improvement efforts, is a longtime Boeing executive who worked directly on a number of commercial jet production programs. And to him, there are absolutely lessons that can be drawn from passenger aviation.

“A jet engine is a jet engine; no one will convince me otherwise,” he said. “I’ve lived in both worlds, I’ve been on more airplanes than anybody in the United States, I know these things, OK?”

The deputy said his focus was on helping the service develop “methods, systems and practices” that will lead to systemic changes in how maintenance is done and provide dividends for years to come.

“When you look at the F-18s, this is the same size of fleet as Southwest has. It’s not a super-large fleet, they’re all basically the same,” Shanahan noted. “So how do we put in place, you know, the support practices and the parts so that people aren’t working as hard?”

The need to keep part quality and quantity up were on display just a day after Shanahan and Neller’s comments. On Thursday, the Pentagon ordered a temporary stop to flying the F-35 as it investigated a fuel tube inside the engines of the fleet. That same day, an F-22 crashed on its side following a landing gear malfunction.

During his talk with reporters, the Navy was singled out as already having committed to improving their methodologies. And he called out the need to “restructure” how both the Navy and Air Force handle their supply chains — something he said will ultimately bleed over into maintenance beyond the four selected jet fleets.

“The real end game to me is as a department, how do we end up with a single sustainment system? And what was good about this is that once you get the F-18 right, it spills over into the P-8, because they're side-by-side, so [the P-8 maintainers] going to be like, ‘Those guys, they're working a lot less hard than we are and they're getting much better results, why don't we just do it that way?’

“And then as people see the methods they apply to shipbuilding or ship maintenance,” he added.

Shawn Snow of Marine Corps Times contributed to this report.