The F-15 Eagle fighter, which first entered United States Air Force (USAF) service in 1976, will continue to be an essential element of America’s air superiority force into the 2040s.  Accordingly, the Department of Defense needs to procure the F-15X, the latest version of this fourth-generation fighter that will remain a vital weapons system even in an era of stealthy fifth-generation fighters like the scarce F-22.

The website Warzone has examined how a “quiet USAF inquiry” prompted the F-15X, not Boeing’s commercial interests (Secretary of Defense Patrick Shanahan, a former Boeing executive, has recused himself from F-15X decisions).  Previously USAF leaders like Air Force secretary Heather Wilson “had been adamant about only buying stealthy 5th generation fighters” and had “myopically focused on” USAF’s F-35.  The USAF procured its last fourth-generation fighters, F-15s and F-16s, in 2001.  

Warzone’s report contrasts that an “all stealth force sounds good, but in reality, it is fiscally unsustainable and not beneficial, and even a hindrance,” for many USAF missions.  In particular, the Air Force, which had 134 fighter squadrons in 1991 during the Gulf War, wants to expand a current strength of 55 fighter squadrons to 60.  USAF’s Air Combat Command General James “Mike” Holmes has therefore emphasized the cost-saving need for an appropriate procurement mix of fourth- and fifth-generation fighters.

Warzone’s article noted that the F-15X “could play a pivotal role in supporting many of the most buzz-worthy air combat concepts being discussed by USAF today.”  Already the “F-15 is the heavy lifter” among American fighters and the F-15X’s “crazy weapons hauling capabilities” could “carry a whopping 22 air-to-air missiles.”  By comparison, the USAF’s current single- and two-seater F-15C/Ds can carry eight air-to-air missiles, and F-15s recently ordered by Saudi Arabia 12, while the F-35 in stealth-mode has only six to eight weapons carried internally.

Therefore a Popular Mechanics article has noted that the F-15X could act as a “glorified missileer, launching missiles on cue from its stealthier cousins.”  The F-15X could also carry a range of large weapons systems like lasers or standoff tactical jammers to support stealth aircraft.  Additionally, the F-15’s combat radius of 1,150 miles versus 870 for the F-35 means that the F-15 “can fly long-range missions while the F-35 is much more a tactical aircraft optimized for relatively short-range missions.”

Concerning air superiority, analysts have noted that the “F-15 is designed for this mission.”  The F-15 has 50 percent greater maximum speed than the F-35 (Mach 2.5 compared to 1.6) and can fly 10,000 feet higher.  Among American planes, only the stealthy F-22 beats F-15s at dogfighting, but USAF has too few of these fighters with 186 units.

At the urging of President Barack Obama, who had threatened to use his veto, Congress made the controversial decision to cancel the F-22 program in 2009, even though USAF had called for a minimum of 381 F-22s.  Analysts have decried that the F-22 is “simply the best air superiority fighter the United States has ever produced and it was a foolish, shortsighted decision to end its production run prematurely.” However, others have noted that the F-22 is a “(highly effective) boutique aircraft” that saw no service during the Afghanistan and Iraq wars, with their emphasis on close air support, although F-22s recently have struck Islamic State targets in Syria.   

Obama and others like Senator John McCain had objected to the F-22’s high cost.  Unit costs had only dropped to $137 million per copy at production run’s end, although continued production would have decreased unit costs to about $90 million, and the F-22 has hourly operating costs of over $68,000.  Congress’ prohibition on F-22 export only increased costs by excluding international development partnerships.

Several factors preclude resumption of the F-22 program, whose origins date to the Cold War in the 1980s when USAF initially sought 750 F-22s, including the simple fact that tools and instructions for F-22 production have gone missing.  The F-22’s “technology is old -- stealth, propulsion, avionics and airframe design have come a long way since the F-22 was designed,” the National Interest has noted.  F-22 “computer architecture dates back to the early 1990s” and the “jet’s antique processors and other components haven’t been made in decades.”  Most F-22 “systems would be hopelessly obsolete” by the end of a projected service life in 2035.

Given such factors, the USAF had already planned to use its present inventory of F-15C/Ds (last built in 1986) until 2042 and the F-15E Strike Eagle, a multirole ground attack version, even longer.  Yet F-15s in service often are older than their pilots and many companies that built the F-15s original parts are now defunct.  Compared to the proposed modern F-15X with digital avionics, existing F-15s have a computer processor comparable to a 1980s Commodore 128 and their cockpits have been described as a “throwback to an analog age.”

While the USAF’s previously planned F-15C/D upgrades would have demanded many millions of dollars per jet, an F-15X modernization offers many savings.  The original F-15s intended to serve individually only 5,000 hours, but the F-15X’s 20,000-hour service life, some 80 service years, is about three times that of most fighters produced globally.   The F-15X’s hourly operating cost of about $27,000 seriously undercuts older F-15s at $45,000 as well as F-35s at about $50,000.  Thus Warzone has noted that the F-15Xs “will pay for themselves in about a decade's time based on operational cost savings over their F-15C/D brethren.”  The “plug-and-play” F-15X additionally uses preexisting F-15 base infrastructure, an enormous cost saving over newly developed fighters.

The F-15X, an advanced version of the Eagles Qatar ordered in 2017, would also benefit from about $5 billion spent by Saudi Arabia, Qatar, Singapore, and South Korea on new technology for their F-15 orders in the past 15 years.  In turn, the former four-star USAF general Frank Gorenc has noted, the F-15X “4^th gen++” or generation 4.5 fighter “can help build partnership capacity with allies and partners who do not need, want or cannot afford a 5thgen fighter.”  Meanwhile in America F-15X production will help sustain a diverse industrial base.

This prior international investment help refute concerns that the F-15X will cost more per unit than the F-35.  While F-35 unit costs are declining towards a targeted $85 million, an F-15X would most likely cost $50-$75 million.  Moreover, Boeing has offered the F-15X under a fixed-priced contract.

The F-15X thus validates the analysis of Dan Grazier, the Jack Shanahan Military Fellow at the Project on Government Oversight.  “Whenever the military possesses a proven basic design like the F-15, the Pentagon should focus its efforts on maintaining and improving it until the state of technology changes to the point where the basic design is no longer viable,” he has noted.  The United States Navy has followed this advice with recent purchases of F/A-18E/F Super Hornets to complement the navy’s F-35 inventory.

Israel likewise seeks a future F-15 and F-35 combination.  In contrast to the F-35, the F-15’s long range is particularly appropriate for targets in places like Iran.  Analysts have noted that for Israel “modern stealth fighters, particularly the F-35, are not a ‘one size fits all’ solution to aerial warfare.”

The F-15 family of fighters evokes the long-serving B-52 bomber, whose storied USAF service began in 1955 and continues today.  While developing new technologies, even beyond those of current fifth-generation aircraft like the F-22, America should not too soon abandon tried and true aircraft platforms.  The F-15 Eagle still has many years to soar.