The GAO Summarizes The U.S. Military's Fleet Of "Tactical" Warplanes

From here.

Air Force Indecision

The F-35A was specifically designed to be the successor to the F-16, so I'm somewhat surprised by the languages saying that the replacement is "to be determined" perhaps alluding to the possibility of a two generation of fight aircraft skip to NGAD. It also isn't clear to me why the F-22 is grouped with the U.S. military's 4th generation aircraft, while the F-35 which we have purchased twice as many of, is considered a "replacement aircraft" rather than a "current aircraft" (which itself is something of a false dichotomy).

The F-35A Is Not A Close Air Support Fighter

The concept of the F-35A as a replacement for the A-10 was a bad one the day that it was conceived and remains a bad idea. Yes, 40 years is too old for a war plane. Technology relevant to military aircraft has improved since 1982 and even if the design was the best possible solution that could ever be designed, warplanes wear out in that time frame.

But by conceiving of the F-35A replacement the A-10, the Air Force basically abandoned its duty to provide close air support to ground troops in the Army, forcing the Army to transfer that mission mostly to its Apache AH-64 helicopter gunships, which are slower, less survivable, are harder to maintain than the A-10.

Close air support for ground troops is a mission that the F-35A is unsuitable for. The F-35A is an extremely expensive (ca. $135 million each), supersonic, stealth fighter designed to drop smart bombs undetected from high altitudes and to engage in air-to-air combat with advanced fighter jets in the kind of sparring we saw between Russia and Ukraine near Kyiv in the early days of the Ukraine War. 

Unlike the A-10, the F-35A isn't optimized to loiter in a small geographic area at low altitude, with line of sight views of the battlefield that help it distinguish friend from foe, within range of possible crude anti-aircraft fire, and to deploy and operate from primitive field airstrips near the front lines. In Afghanistan, the Air Force even tried to press the B-1B bomber into that role in lieu of the F-35A and that experiment was a failure.

As a result, the task of providing close air support to the Army's ground troops and hunting tanks has been primarily turned over to the Army's own AH-64 Apache helicopter gunships, which are slower, have a shorter range, are less survivable under fire from opposition ground troops, and are harder to maintain in the primitive conditions of the front lines of ground warfare. Armed drones like the MQ-1 Predator and MQ-9 Reaper have also picked up some of the slack.

The DOD's Concept Of Slots That Need 1-1 Replacement With New Models Is Thoughtless, Ill Informed, And Expensive

As the technologies surrounding war with aircraft has changed, and as we have learned from years of history since the nation's fleet of 4th generation fighters was devised in the 1970s and 1980s, the number of aircraft and mix of needs of our military has changes, but the GAO simply proceeds by rote, something particularly disappointing in the case of an agency whose mission is to identify unnecessarily expensive and ineffective federal spending programs.

What's changed?

* We've learned that fighters with extreme capabilities can be expensive overkill for some mission.

The U.S. should substitute expensive top of the line fighters for less expensive, less capable warplanes for missions that don't require 5th and 6th generation fighters. Even when 5th and 6th generation fighters can be used to fight and win against low end opponents, their extreme cost hurts the U.S. in the long run war of attrition against low end opponents.

We've learned that many of the missions that U.S. tactical warplanes need to fulfill don't require the capabilities like supersonic speed and stealth that made the F-22 and F-35 so expensive, and make even the F-15, F-16, and F-18 expensive overkill. Homeland defense and attack aircraft missions in secure airspace are two of those instances of overkill.

Homeland Defense

One of those missions is protecting U.S. airspace from errant civilian aircraft and warplanes improved by irregular insurgent military forces from civilian aircraft. This role is currently carried out mostly with a significant number of F-16 and F-35A aircraft when alternative "homeland defense interceptors" that lack stealth, bombing capabilities, supersonic speeds, and the capacity to maneuver in extreme "Top Gun" style dog fights could do the same job with much lower acquisition and operational costs and would be much easier to train Air National Guard and Air Force Reserve pilots to operate.

The Light Attack Aircraft Mission

Another mission for which the F-15, F-16, F-18, F-22 and F-35A are expensive overkill is the task of serving as a low capacity bomber or close air support aircraft in operations in which the U.S. has secured air superiority and our opponents do not have sophisticated anti-aircraft missiles or have only a few MANPADs (like the infantry carried and operated Stinger anti-aircraft missile). This was the situation in the later days of the wars in Iraq and Afghanistan, and has a decent probability of presenting itself in operations that the U.S. could become embroiled in at some future date in Latin America, Africa, or Southeast Asia.

An aircraft that only needs to drop smart bombs or launch guided missiles from altitudes sufficient to stay out of range of small arms fire that needs only minimal air to air combat capabilities, can be much less expensive to buy and operate, and much easier to train pilots to operate. Our allies in Iraq and Afghanistan, and many of the countries where these capabilities would be useful have procured inexpensive warplanes for this purpose and there is a place for these kinds of warplanes in the U.S. military.

Light attack aircraft aren't a perfect substitute for the A-10, but they are well suited to carrying out many of its roles.

The Transport Bomber Mission

Another mission that doesn't require sophisticated and expensive tactical fighters or ultra-expensive stealth bombers is launching long range guided missiles far from battlefields and dropping smart bombs from high altitudes that are beyond the range of our opponents, in uncontested airspace.

Given the fact that in all but a handful of conflicts since the 1980s, a short air to air combat phase of a conflict was followed by a long period of time where the more technologically sophisticated military had air superiority, this has proven itself to be a common military aircraft mission that can be performed perfectly adequately with less expensive and sophisticate aircraft, even when the bomber needs to deliver more ordinance in a sortie than a fighter or light attack aircraft can handle, or needs the range to operate from more distant airbases than fighters or light attack aircraft can manage.

This mission doesn't even require dedicated bomber aircraft. It can be met with simple  military and civilian cargo planes flying out of general aviation grade airports carrying palletized missiles with few design tweaks from their civilian versions.

* Pre-Smart Bomb Fleet Sizes No Longer Make Sense

The current size of the U.S. tactical aircraft fleet was designed around the large number of sorties required to destroy each target before U.S. warplane began to almost exclusively use smart bombs and guided missiles. But it has been the case for decades now that U.S. warplanes in bombing missions come very close to the ideal of one shot, one kill for almost all of their targets. It now takes less than a tenth the number of planes to destroy the same number of targets in hostile territory that it did when the number of 4th generation fighters that the U.S. military needed was determined.

The character of air-to-air combat has also changed dramatically. In the predominant case (which is itself very rare) air-to-air combat involves an aggressor warplane identifying the warplane it seeks to destroy and launching a guided missile that will usually destroy the target warplane on the first shot before the target even knows that the warplane trying to shoot it down is there. In a minority of cases, a near peer target warplane with an exceptionally capable pilot will realize that it is under attack before it is too late, will manage to escape the incoming guided missile and possibly return fire with a guided missile of its own (not infrequently downing the aggressor aircraft as a result). Prolonged air-to-air dogfights and slug throwing cannon fire in air-to-air dogfights have almost disappeared, in favor of a first to see, first to kill strategy with highly accurate and effective air-to-air guided missiles. Victory in the rare instances of air-to-air combat that still happen generally goes to the first warplane to identify an opponent within range.

Certainly, past experience does not guarantee future results. The most capable potential opponents that the U.S. could face in air-to-air combat are Russia and China. 

Russia's failure to utilize what was widely perceived to be its superior air forces in the Ukraine War to secure air superiority in that conflict, however, continues to be a mystery. This failure casts doubt on how serious a threat Russia's air forces would be in an effort by the U.S. and its allies to gain air superiority in a conventional war with Russia.

China's air forces also look impressive on paper and its military is unlikely to be as hollow as Russia's military has proven itself to be. 

The United States which has fought small wars continuously with only brief interruptions from the Korean War through the conclusion of the war in Afghanistan in 2021, demonstrating its military capabilities in ways that can't be hidden or faked. The world knows most of the U.S. military's strengths and weaknesses to a considerable degree of accuracy.

But China's military has fired shots in anger only vary rarely since the Communist regime came into power, and some of the few wars and battles it did participate like the border war in the Himalayas between China and India in the 1960s, and its occupation of Tibet, took place more than half a century ago and sheds little light on the state of its military forces today. 

Recent Chinese military exercise that have been part training and part P.R. and saber rattling, have provided a glimpse of China's military capabilities, but the truth of the matter is the no one, not even the Chinese, know for sure how the Chinese military would perform in actual combat against opponents with advanced military forces and a U.S. military ally, like Japan, South Korea, and Taiwan. The mission of defending these three East Asian allies of the U.S. against military threats from China, Russia, and North Korea is by far the most demanding driver of the U.S. military's need for advanced air and naval power.

But even in a notional conflict with China or North Korea or Russia or Iran, in East Asia or in Europe or in the Middle East, the U.S. mission is pretty much limited to defending countries which are U.S. allies from invasions or attacks from one of these handful of possible aggressors as part of a coalition of allied countries with advance military forces.

There is no reasonable or foreseeable scenario in which the U.S. military, with or without support from its allies, would seek to invade or occupy any significant part of China, Russia, North Korea, Iran, Libya, Myanmar, Vietnam, Cambodia, Laos, Cuba, Mexico, Brazil, Argentina, Peru, or Nigeria, to provide a few examples, for any longer than it took to destroy some critical military resource in one of those countries and leave, at least for any area larger than a tiny beachhead enclave like Hong Kong or Macau or Guantanamo Bay.

U.S. troops in a ground war with Russia in Europe would be fighting on the territory of allies like Lithuania, Finland, Poland, Germany, Ukraine, or Turkey as part of a coalition made up of most or all of the nations in NATO. This, of course, assumes that a large scale conventional war could be fought there at all, as it has been in Ukraine, without going nuclear.

U.S. troops in ground war in East Asia with China, North Korea and/or Russia would be fighting on the territory of Japan, South Korea, Taiwan, Guam, the Mariana Islands, the Philippines, Fiji, or Samoa, in a coalition that would, at a minimum, directly include the military forces of the defended nation and indirect logistic and regional sea and airspace support from the other U.S. allies in the region. Again, this assumes that a conventional warfare conflict like this could be fought without the U.S., China, or North Korea resorting to the use of nuclear arms. In the face of a nuclear attack, the U.S. and its allies might conceivably resort to occupying North Korea, but even in the face of a nuclear attack, the U.S. and its allies would probably not try to occupy any significant amount of territory in China.

It is also virtually unthinkable that Russia would try to make any deeper incursion than a quick strike and retreat against key military or economic targets in Alaska beyond the Aleutian Islands, or that either Russia or China would seek to occupy Hawaii even if one of those countries attempted to replay the Pearl Harbor scenario there. 

The losses Russia's Black Sea fleet has suffered at the hands of Ukraine which basically doesn't even have a navy of its own and hasn't deployed its warplanes against Russian naval forces and the mishaps its major warships have suffered through accidents in recent years, also suggests that Russia's Pacific naval fleet is highly vulnerable and hollow.

Similarly, North Korea has no meaningful ability to deploy ground troops even to China, South Korea, Japan, or Russia, despite the immense number of soldiers and reserve forces it has relative to its population, as its military (with the possible exception of its nuclear missile capabilities and perhaps its capacity to harry commercial and military ships with its submarines) is undoubtedly hollow. North Korea isn't strong enough militarily to invade anyone.

Considering the scope of the plausible wars that might be fought in these regions is relevant to determining what air power the U.S. military needs now. 

The right approach to determining how many and what kind of warplanes the U.S. military needs is to analyze the handful of plausible scenarios like the ones above one by one with reasonable assumptions about what kind of fight with what objectives it would be, who our allies would be and what their military resources are, and with whom we would be fighting in each conflict (considering also their allies) having what military capabilities, rather than simply seeking to replace legacy warplanes one for one with new warplanes of the same kind.

This needs analysis should also consider the extent to which these needs could be better met by helping to arm our allies with modern weapons.

This needs analysis should also consider any circumstances in which diplomacy could mitigate these needs. For example, a treaty might limit conventional arms that are expensive to counter like hypersonic missiles or submarines. 

Or, diplomatic arrangements could secure long term stable international arrangements between our allies and our potential adversaries that would eliminate the likelihood of one or more future military conflicts. For example, a mutually agreeable long term resolution of the conflict between the People's Republic of China and Taiwan.

Other Considerations

A determination of the right size and mix of aircraft for the U.S. military's fleet of aircraft should also consider some additional factors;

* Intense battles for air superiority in a theater are likely to last only for weeks or a few months, this part of any given regional war is unlikely to to be fought with full strength at the same time as another regional war, and air power can be relocated from one theater to another anywhere else in the world in a matter of a few days. Once air superiority is achieved in a theater, it needs far fewer warplanes at once there. The requirement that the U.S. military be able to fight two regional wars at full intensity at the same time is excessive for warplanes that can be swiftly relocated to any other theater of warfare in the world in a matter of hours or days.

* A large share of U.S. warplanes can and should be replaced with unmanned armed drones and/or cruise missiles. This is ready for prime time technology not just for aerial refueling, small counterinsurgency strikes, deploying bombs and missiles in preplanned strikes, and transport planes. Carrier and land based unmanned fighter planes with capabilities comparable to 5th generation fighters are viable now. It isn't necessary or appropriate to replace all or almost all warplanes with combat drones, but a lot of them can and should be replaced. They are smaller and cheaper for comparable capabilities, don't put U.S. warplane crews in harm's way, can take risks that would be unacceptable for manned warplanes, and can perform maneuvers that would leave human pilots overwhelmed by G-forces or too dizzy to operate their planes at full capacity.

* U.S. warplane fleets (such as the P-8 maritime patrol aircraft and long range bombers like the B-21) supported by aerial refueling, should assume tasks currently performed by U.S. warships, like strikes on enemy surface ships, strike on distant ground targets, and a significant share of anti-submarine warfare. In particular, many of the missions assigned to the U.S. Navy's guided missile destroyers could be done better by warplanes which have equally potent offensive capabilities, are much less vulnerable to various kinds of enemy attacks, put far fewer U.S. military service people in harm's way, and are less expensive and more easily shifted where needed on short notice. This, however, requires more searching examination of the U.S. air power logistics chain if degraded by enemy attacks to determine what warplane resources can deploy from ground bases possibly far from the places that the planes will strike, and what warplane resources are best suited to naval carrier based deployment.

* Some functions served by warplanes, however, can be better provided by ground based guided missiles that ground forces control, can be much less expensive than warplanes using guided bombs and missiles, are easier to train service members to use, and can continue to be useful even if air superiority is lost. 

The U.S. has slighted its high end surface to air missile capabilities against enemy aircraft for the reasonable reason that it has kept air superiority in all recent conflicts, but that isn't a situation that is guaranteed to recur every time and the existence of the capability can deter enemy forces from trying to use their warplanes in the first place.

Similarly, resources like HIMAR multiple rocket launcher batteries  and Switchblade "loitering munitions" and ground based anti-ship missiles, like the Naval Strike Missile batteries that the U.S. Marine Corps is planning to deploy, can eliminate the need to strike parts of enemy bases, artillery batteries, sensor resources, and warships that aircraft when this would have required attack aircraft sorties in the past.

Off Topic: The Submersible Special Forces Delivery Airplane That The U.S. Studied But Didn't Buy

Another interesting article examines warplanes that the U.S. seriously considered but didn't end up buying. 

Many were familiar but I hadn't heard about the "Flying SDV" which is something out of a James Bond movie (which actually did feature something similar in one case).

A declassified Navy program from 2010 shows a concerted effort to field flying submarines, or SEAL Delivery Vehicles (SDVs), for high-risk special operations.

The Navy’s 2010 study largely leveraged DARPA’s outlined requirements, or Concept of Operations, for a submersible aircraft aimed at transporting special operators. The first was obvious: that the flying submarine could be deployed from existing Navy or auxiliary platforms. The vehicle had to be able to land and take off unassisted from the surface of the water, with an in-flight range of 400 miles or more. It needed to be able to transit at least 12 miles once submerged, and loiter for up to 72 hours while hiding from detection. Perhaps most importantly of all, it also had to be able to traverse those same 12 miles beneath the waves and 400 in the sky on the way back, as well. Two designs were ultimately developed.

Both designs leverage multiple watertight compartments, with one keeping the two-person crew separate from a single personnel compartment capable of carrying six special operators, and the other using two smaller personnel compartments that could each hold three. In both designs, the wings would carry fuel in a membrane that would allow any unoccupied space in the wings to be flooded with seawater while submerged. Likewise, the personnel compartments were intended to be free-flooding when the vehicle was underwater.

Two turbofan motors would propel the vehicle while in flight and on the surface of the water, which would be sealed using torpedo-style doors while submerged to protect them from seawater. Submerged propulsion would be managed by a drop-down azimuthing pod with electric motor, capable of maintaining a speed of 6 knots.

Both variants of the flying submarine concept were to operate at depths of around 30 meters (98.4 feet) and be able to take off and land on specially designed inflatable floats.