The Navy's aging F/A-18 Hornet fleet will remain as is still on the books as the bulk of the Navy's service's strike fighter power into the next two decades, forcing the service to extend the every airframe's aircrafts' life from its initial 6,000 hours to 10,000 and possibly beyond.

About 40 F/A-18 A-D Hornets went through upgrades at Fleet Readiness Center Southwest in San Diego in the last fiscal year, according to Naval Air Systems Command statistics, and 50 more are scheduled for the current fiscal year. fiscal year 2015.

Those revamped Hornets will stay in service as the Navy transitions to the F-35C Lightning II joint strike fighter in the next decade, with F/A-18 E/F Super Hornets remaining in squadrons online to complete the transition through the 2030s, the Navy's air boss said in his first sit-down interview with Navy Times. told Navy Times Feb. 26.

"[The extended Legacy Hornets] are kind of — I don't want to say gap-fillers — but they will be the biggest chunk of our carrier fleet through the middle to the end of the next decade," said Vice Adm. Mike Shoemaker, who took over Naval Air Forces Jan. 22 said. "So as we have used those legacy Hornets, we have had to extend their life to get through to when we can introduce JSF."

In 2014, the head of Navy Fleet Readiness Centers told Seapower magazine that plans were in the works to start extending Super Hornets to 10,000 hours as well during fiscal '15, to keep them in service when the last of the legacy Hornets is retired finish phasing out in 2022.

Originally, Rear Adm. Paul Sohl said, the Navy "had an acquisition strategy to replace old F/A-18s with newer ones, and replace those with F-35s," but the strategy "got messed up."

The Navy has been the F-35's smallest customer so far, ordering two new aircraft for 2015, which lawmakers doubled to four. In the first seven years of production, the Navy has ordered 30 F-35s. The Navy has ordered four of the stealth fighters for fiscal 2016. which would bring the grand total to 28 in the first seven years of production, according to inventories cited in the most recent Congressional Research Service Report on the JSF program.

The Marine Corps, by contrast, requested six F-35Bs and the Air Force requested 26 F-35As, bringing their totals to 66 and 130, respectively.

Some experts, including Teal Group analystis executive Richard Aboulafia,have said the Navy's low buy-in is a symptom of ambivalenceindifference toward the F-35's high-tech advancements, including stealth capabilities.

Stealth has been a key selling point of the F-35, but the chief of naval operations doesn't appear to be overly enamored with it. Speaking recently about the yet-to-be designed, next generation carrier-based fighterat the Naval Future Force Science and Technology Expo in February, Adm. Jon Greenert argued that it must have a full spectrum of weapons, but "stealth might be overrated."

Chief of Naval Operations Adm. Jon Greenert has cautioned that against a yet to be designed future carrier-based fighter to include stealth — a key selling point of the F-35. echoed that sentiment in remarks at the Naval Future Force Science and Technology Expo in February, saying that while the next generation fighter must have a spectrum of weapons, "stealth might be overrated."

For his part, Shoemaker, however, said he is eager to introduce F-35s. The Navy's fiscal year 2016 budget proposal doesn't include any more Super Hornets, though it does fund the legacy version's life extension.

"I am very excited about introducing the Lightning II into the fleet. I would like to do it sooner rather than later," said Shoemaker, an F/A-18C Hornet pilot. "I mean, this is not my choice to extend legacy Hornets. We are there because ... there have been some Navy-wide decisions on the procurement rate of JSF."

Budget constraints have limited the Navy's orders of both F-35s and Super Hornets, he added, prompting the Hornet overhauls to bridge the gapforcing the life extensions.

"But now we want to keep the current buy rates, and if there is a possibility to increase those a little bit, we will do that," he said.

Like a 'classic car'

The Hornet and Super Hornet, introduced to the fleet in the early 80s and mid-90s, respectively, can theoretically fly past their 10,000-hour life extension, but it's unlikely to happen, an FRCSW spokesman said.

"They were originally designed for 6,000 hours, they tested them for 12[,000], so going past 10,000 is probably not something they're going to do," Mike Furlano said.

FRCSW's commanding officer, Capt. Tim Pfannenstein, described the life extensions as inventory management, to make sure the Navy has enough strike fighters online to get it through the next two decades as F-35s trickle in.

"There's a requirement on the flight line," he told Navy Times on Feb. 25. "So if some aren't coming on time, we need to keep others in service."

Complicating the process, Pfannenstein said, is the fact that each aircraft is totally unique, and its parts are no longer available because the legacy Hornet is out of production.

"You can compare it to a classic car," he said.

Once engineers open up the hood, so to speak, each repair needs a custom solution.

One jet, Furlano said, had a crack in one of its bulkheads. Rather than manufacture an entirely new panel and spend the time taking the aircraft apart to install it, he said, the engineers created a brace in-house to cover the crack and support the structure.

According to Navy statistics, about three dozen squadrons are flying Hornets and Super Hornets, with Hornets slated due to keep flying until about 2022.

"I would like, obviously, to get out of those as quick as we can, but the reality is we are going to manage that inventory to get through to current buy rates," Shoemaker said.

Super Hornets will leave service around 32035.