The F-15X: The Air Force’s Next Super Fighter or Waste of Time?

The worthwhileness of the F-15X concept comes down to whether you believe the Air Force should pay to maintain a lower-tier force of cost-efficient fighters to handle missions that don’t require the F-35’s special capabilities, namely air defense of coastlines, munition hauling, and ground support in semi-permissive environments.

bySebastien Roblin

The aviation world is abuzz with rumors that the U.S. Air Force is evaluating the purchase of a brand-new F-15X model of the legendary 45-year-old F-15 Eagle twin-engine fighter. Marcus Weisgerber first reportedthis possibility for Defense One, then expanded upon in an article by Tyler Rogoway at The Drive.

Were a contract to materialize, the F-15X could become the Air Force’s first new fighter that wasn’t a stealth jet since 2001—paralleling a recent decision by the U.S. Navy to procure Super Hornet jets to serve alongside its F-35C stealth fighters, rather than allowing the F-35 to replace them. But just how significant are the upgrades, and do they justify purchasing more of the Air Force’s oldest active fighter plane?

Replacing the F-15C/D:

The F-15X is specifically intended to replace a fleet of 235 F-15C and two-seat F-15D fighters deployed for air defense of the coastal United States, Japan and England. These air-superiority fighters are fast (Mach 2.5), maneuverable and boast long-range APG-63(V)3 radars. However, the F-15C/Ds date back to the mid-1980s and are quite likely to be retired early, as they would otherwise require expensive upgrades to remain airworthy.

Boeing proposes to manufacture new multi-role F-15Xs based on an advanced F-15QA Strike Eagle variant currently in production for Qatar. Because the factory line will remain open through 2022 and the technologies have all already been developed, Boeing could skip over the development phase and plans to offer the F-15X at a (presumably low) fixed cost—rare in an industry known for gigantic cost-overruns. The USAF, for its part, could inexpensively adopt a plane for which it already has existing infrastructure and familiarity.

Many F-15X improvements are sensible rather than slick, trading out the F-15C’s 90s-era hybrid avionics for full fly-by-wire systems, modern digital displays and helmet-mounted sights. New strengthened wings and more fuel-efficient F110 turbofan engines would give the F-15X a remarkable 20,000-hour flight life, enough to last many decades of service. The new engines, which can be more cheaply maintained, also decrease the cost of operating an F-15X to $27,000 per flight hour from roughly $42,000. Rogoway claims this means replacing F-15C/Ds with Xs would pay for itself in ten years.