The U.S. Air Force is having another one of those quixotic debates, this one between backers of the F-35 joint strike fighter and those who fancy the F-15X Eagle, a souped-up version of the tried but non-stealthy fighter jet that has constituted a mainstay of U.S. air operations since the 1970s. Existing F-15s are outliving their service lives, having rendered good service for decades. Many are not slated for replacement by F-35s. Ergo, the Pentagon floated a request for eight F-15X airframes in its 2020 budget submission to Congress.
Budgeteers’ evident goal: to replace aged F-15s with the latest model over the next few years, potentially on a one-for-one basis. Seems straightforward, n’est-ce pas?
But as Clausewitz might say: everything in force planning and procurement is simple, but the simplest thing is difficult! The proposed F-15X acquisition found favor with some aviation enthusiasts while alarming others. To date the objections have dwelt mainly on cost and operational effectiveness. Set aside the cost differential for a minute. It remains unclear what the upfront price of a new F-15 airframe will be or how the cost to maintain and fly it will stack up compared to an F-35. How the numbers tally up matters. Spending about the same or more on a lesser capability would make little sense.
The debate over operational effectiveness is the quixotic part. It’s weirdly isolated from reality. F-15X detractors contend that non-stealthy warbirds stand little chance in a high-intensity threat environment populated by peer aircraft and state-of-the-art integrated air defenses. So what? F-15Xs might perish if air commanders hurl them into combat without support from other aircraft types—but what commander would do so? An air force is a composite organism. Its subsidiary parts—specialized parts of the aerial fleet—render mutual support to one another in battle. The organism survives, thrives, and attains its goals if each part performs its function in sync with the others.
Who cares whether one limb can do it all on its own?
Sea-power scribe Julian S. Corbett explains how military interconnectedness works in a saltwater setting. Three symbiotic parts constitute a navy: the battle fleet, made up of “capital ships,” brawny combatants that fight for, obtain, and defend “command” of waters where the navy must go to accomplish its goals; “cruisers,” lightly armed warships that are cheap enough to build in bulk to police the sea; and the “flotilla,” even lighter, more plentiful craft meant mainly for administrative duty. The battle fleet takes the brunt of the fighting, then stands guard over its humbler cousins while they exploit command.
But, says Corbett, capital ships—meaning armored battleships or battlecruisers in his day—cannot make up the entire navy. However desirable their hitting power and defensive strength may be, they are simply too big, too specialized, and too pricey to afford in large numbers. They wrest away command, then cruisers and flotilla craft exercise command under the battle fleet’s watchful gaze. Only if a defeated foe manages to regenerate combat power and mount a fresh challenge will heavy ships again lumber into action.
F-35s and kindred stealth aircraft represent the aerial counterparts to the battle fleet. They duel enemy air forces and ground defenses for command of important skies. Non-stealthy aircraft equate to Corbett’s cruisers and flotilla ships. They fan out once air superiority or supremacy is in hand, bombarding fixed sites or furnishing close air support under the protection of the air force’s heavy hitters. If the enemy regenerates combat power, then stealth aircraft must renew the fight for command. And on the symbiosis goes.
So it’s misleading to rip an individual airframe out of the setting in which it will actually do its duty and depict it as wanting. Declaring that a destroyer or torpedo boat of Corbett’s day couldn’t stand up to a hulking battleship would have been a trivial statement, so obvious and irrelevant it hardly needed saying. Whether such a craft could perform its duties within the context of the fleet represented the true measure of its fitness. So it was with steam-driven navies of yore, so it is with ultramodern air forces and the warplanes that comprise them.
Which brings us back to dollar signs. Suppose F-35 advocates are right. Suppose the F-15X proves as expensive as its stealthy brethren—or nearly so—and suppose aircraft manufacturers boast the capacity to build enough joint strike fighters to replenish the F-15 inventory. Then replacing worn-out planes with F-35s would make eminent good sense. One imagines Julian Corbett would have stocked the fleet entirely with capital ships if his Royal Navy could have outfitted and operated them for the same price, hull for hull, as cruisers and flotilla vessels. Why not procure excess combat power if it costs no more?
That was not reality for navies a century ago and likely never will be. It might be for the U.S. Air Force. Ultimately, then, this decision about force design, operations, and air strategy may fall to lawmakers and the green-eyeshade folk who advise them.
