The U.S. Navy is still developing aggressor/adversary aircraft for their Top Gun adversary training program. This program requires aircraft and pilots who can accurately emulate the performance of hostile aircraft and their pilots. Currently the navy is upgrading 22 Swiss F-5E fighters recently acquired to serve as aggressor aircraft. The latest upgrade turns the aircraft into an F-5N and reflects upgrades in comparable enemy aircraft.
The latest F-5 acquisition is in addition to the initial 44 F-5E fighters obtained from Switzerland nearly two decades ago. The U.S. uses F-5s, a 12-ton fighter roughly similar to the MiG-21 (or Chinese J-7), for training American pilots to realistically deal with potential enemies. The F-5 is normally armed with two 20mm cannon, and three tons of missiles and bombs. The U.S. Navy modified and refurbished the Swiss F-5s so they performance of current MiG-21/J-7 models.
The Swiss once had a fleet of 110 F-5s, but have been selling them off since 2000. They have 56 left, and a recent opinion poll showed that 65 percent of the voters want to keep them, possibly because the government wants to buy $50 million aircraft to replace them. The U.S. paid the Swiss about $1.2 million for each of the F-5s, then spent a little more per aircraft to refurb them. Acquisition and upgrade cost for the latest 22 are about the same as for the first 44.
The MiG-21/J-7 is still widely used even though it is a 9.5 ton, 1950s design, that became the most widely produced post World War II fighter with over 10,000 built. It is cheap and easy to maintain but no longer effective. Many nations keep them in service because of their low cost, and because a wide range of avionics and weapons upgrades are available. The Chinese have long offered their copy of the MiG-21, the J-7 and produced and upgraded them even after Russian halted production in 1985. J-7 production ceased in 2013. Not really designed for ground attack, these aircraft can carry 1.5 tons of bombs. U.S. pilots are much better at killing MiG-21/J-7s once they have trained against an F-5 being flown like these similar aircraft.
The new batch of F-5Ns will be distributed in about ten smaller detachments to operate at air bases where fighters are stationed and want to provide all their pilots with some adversary training. Normally pilots do not have such access to the three aggressor squadrons (two navy, one marine) which are based at special training facilities where all the participants can be tracked electronically to provide a more accurate post-training commentary on how the pilots reacted and performed during the confrontations with the aggressor aircraft.
When acquiring aircraft to be used for adversary training there are sometimes unique problems. That was the case as the navy and air force began receiving F-35 stealth fighters. Air Force and Navy pilots faced a training problem, one they have encountered before when they encountered unexpected results with new aircraft and weapons going into combat for the first time. After American participation in the Vietnam War ended in 1972 Israel became the country that got to use new American aircraft and new weapons first. Th Israeli also benefited from the American development of adversarial training during the Vietnam war.
The first time the lack of adversarial training was during was during the 1960s when the air force and navy aviation suffered unexpectedly high combat losses because their aircraft and pilots were not prepared for the lower tech Russian aircraft used against them over Vietnam. The initial solution was for fighters to be again equipped with cannon because the new air-to-air missiles were not yet reliable enough to replace the “old fashioned” cannon. That did not change the situation a lot and that led to a solution that did work. This was the concept of using your own aircraft for "aggressor (or dissimilar or adversarial) training." This began in 1969 when the U.S. Navy established the original "Top Gun" fighter pilot school. As the years went by the air force and navy acquired more Russian warplanes to use for training in addition to using Western fighters equipped and flown in the same manner as the potential opposition.
In the 21st century the 1960s solution did not work as well. This is becoming a serious problem as more air force and navy pilots prepare to switch from F-18s, F-15s and F-16s to F-35s. These transition pilots are finding that Top Gun type training needs much better adversary aircraft because potential foes (China and Russia) have improved their tech considerably since the American stealth aircraft entered service in 1983 (F-117) and 2005 (F-22). Potential opponents hustled to deal with that and Russia and China had both adopted adversarial training and were working on solutions. The F-35 began entering service in 2015 and Israel was the first export customer to receive F-35s, in 2017, and put them to work against Iranian forces in Syria. Russia had their most modern air defense systems in Syria and found that their preparations to deal with the F-35 were inadequate. That had already been demonstrated when F-22s earlier flew missions over Syria.
For the Americans the F-35 success in Syria meant that adversarial training against new Chinese and Russian stealthy aircraft would have to do better than Russian efforts. U.S. Navy F-35s have since operated in the West Pacific and within range of Chinese air defenses but nothing has been made public yet about Chinese reactions. The Chinese have stealth aircraft operational but they have not yet been deployed against F-35s. That may change soon because South Korea and Japan have also received F-35s and two countries often get unwelcome visits by Chinese aircraft,
Given the prospect of stealth versus stealth aircraft, the old rules of adversarial training must adapt. That means adversary aircraft equipped with the advanced tech (like AESA radars and more complex electronics in general). One aspect of this problem is that the military uses commercial firms to supply aircraft and retired (and very experienced) military pilots to fly the dissimilar aircraft. Current laws prohibit the commercial firms from obtaining the high-tech fighters required to adequately challenge F-35 and F-22 pilots. Using the more advanced dissimilar aircraft is also more expensive and the senior air force and navy leadership now understand that this is an essential cost. But there is general agreement that these changes are needed. Apparently Israeli experience with their F-35s have reinforced the call for more realistic Top Gun opposition.
This is a relatively recent problem. The F-22 began development in the late 1980s, first flew in 1997, and entered service in 2005. The F-22 has performance that was (and still is) far superior to that of any other aircraft in service. The combination of speed, advanced electronics, and stealth technology has created such a decisive advantage that F-22s are often matched up against as many as six F-15s to ensure their pilots face a challenge during training. So why is the F-35, with somewhat lower performance, causing such a commotion? The problem is that because of high cost only 187 F-22s were built. But more than 20 times as many F-35s will enter service, many of them with allied air forces. For the dissimilar training to work the F-35 must face aircraft that can realistically mimic what the latest Russian and Chinese fighters are capable of. That led to some little-publicized innovations, like taking some F-117s out of retirement and putting them back to work as adversarial aircraft. The last of the 64 F-117s built was officially retired, but not destroyed, in 2008. As early as 2009 F-117s have been spotted in the air and more followed as they were needed for Top Gun and Red Flag.
Before dissimilar training, American pilots practiced against American pilots, with everyone flying American aircraft and using American tactics. It worked in World War II, because the enemy pilots were not getting a lot of practice and were using similar aircraft and tactics anyway. Most importantly, there was a lot of aerial combat going on, providing ample opportunity for on- the- job training and development of new tactics. Not so in Vietnam, where the quite different Russian trained North Vietnamese were giving U.S. aviators an awful time. The four-week Top Gun program solved the problem. The air force followed shortly with its Red Flag school. In the early 1980s, the Russians established a dissimilar air combat school and the Chinese followed in 1987 as did the Russians in the 1990s.
Since the 1970s the two American training programs have developed differently, and the entire concept of "dissimilar training" has changed. The navy kept Top Gun as a program to hone fighter pilot's combat skills. The air force made their Red Flag program more elaborate, bringing in the many different types of aircraft involved in combat missions (especially electronic warfare). But after the Cold War ended in 1991, it became increasingly obvious that none of our potential enemies was providing their fighter pilots with much training at all. In other words, the dissimilar training for U.S. fighter pilots was not as crucial as it had been during the Cold War. It had been noted that flying skills of Soviet pilots were declining in the 1980s, as economic problems in the Soviet Union caused cuts in flying time. During that period American pilots were increasing their flying time. Moreover, U.S. flight simulators were getting better. American pilots were finding that even the consumer grade combat flight simulators had some training value.
Because the Cold War was over and no similar opponent appeared, in the late 1990s Top Gun and Red Flag found their budgets cut. But the programs remain, as does the memory of why they were set up in the first place. In the 21st century China was rapidly improving its combat aviation and giving its fighter pilots more flying time. Chinese politicians maintain a bellicose attitude towards the U.S. and it is accepted that there is a need to increase American Top Gun training. Because of the new Chinese "dissimilar training" effort, the U.S. Top Gun and Red Flag schools were restored to their former prominence, sort of. The Chinese move is certainly a very meaningful one, as it shows that they are serious about preparing their pilots to fight and defeat Taiwanese and American pilots. Dissimilar training is how that is done.