The balance of air superiority over the island of Taiwan is slowly shifting. Once assured by a fleet of sleek, modern Republic of China Air Force fighters, the rise of China—and the decline of Taiwan’s defense budget—has gradually changed the equation in favor of China.

Following the end of the Chinese Civil War, the government of the Republic of China evacuated to the island of Taiwan. Less than two hundred miles separate the island from a hostile Chinese mainland. Yet as long as Taiwan maintained a strong navy and air force, and more importantly, as long as China remained poor, Taiwan might as well have been on the far side of the moon.

But China is no longer poor, and it is building a military that matches its newfound wealth. China is able to build more combat aircraft than Taiwan can support, and has embarked on a two simultaneous fifth generation fighter programs.

The Chengdu J-20 “Soaring Dragon”—which is currently in development—will be one of the most dangerous threats ever posed to Taiwan’s national security. A large, twin engine aircraft with stealthy characteristics and long range, a version of  the J-20 (and there may indeed be more than one) might be configured as a long-range air superiority fighter.

Previous Chinese fighters were hobbled by relatively short ranges that limited the amount of time they could spend over Taiwan. The J-20, with its long, wide fuselage has plenty of room for internal fuel storage. The J-20 will be able to sortie from mainland bases and have the fuel to conduct fighter sweeps over the island, hunting Taiwan’s air force. If the J-20’s stealthy design is effective as its might designers intend, Taiwanese radars could have difficulty tracking the fifth generation fighter.

The J-20’s suite of sensors probably include a new nose-mounted active electronically scanned array AESA radar—currently thought to be under development—and an infra-red search and track (IRST) system, which would allow it to passively track and shoot down aircraft enemy planes.

Once over the island, the J-20 might be able dish out a formidable amount of firepower. The Soaring Dragon has three internal weapons bays—two for short-range missiles and one for medium to long-range missiles. A normal payload for the air superiority mission might be four PL-9 infrared short range missiles and four PL-15 radar-guided long-range missiles. Powered by a ramjet engine, the PL-15 might have a range anywhere between ninety-five to 125 miles.

The J-20’s primary Taiwanese opponent, the F-16 Fighting Falcon, is a different beast altogether. Originally a lightweight, day-only fighter design to complement the U.S. Air Force’s F-15 Eagle, the F-16 has evolved into an all-weather multi-role aircraft. Relatively inexpensive and capable of a wide variety of missions, the F-16 was a good fit for Taiwan.

Taiwan’s 150 F-16A Block 20 aircraft were ordered in 1992 and delivered between 1997 and 2001, making the oldest nearly twenty years old. The Block 20 version included an AN/APG-66(V)3 radar capable of guiding AIM-7 Sparrow and AIM-120C7 AMRAAM medium-range radar-guided missiles, Raytheon electronic countermeasures pods and a Pratt & Whitney F-100-PW-220 turbofan engine.

In 2011, an order for sixty-six new F-16s fell through. Subsequently, the United States and Taiwan concentrated on upgrading the island nation’s existing F-16 fleet. Most of the improvements will be “under the hood”, consisting of sensor, navigation and armament upgrades. Each will be equipped with the APG-83 Scalable Agile Beam Radar (SABR), a new radar system with hardware and software derived from the F-22 and F-35 radars.

Taiwan is also considering equipping F-16s with the SNIPER pod, an air-to-ground precision targeting pod that is also useful in an air-to-air infrared search and track role. In addition to the pod, the Taiwanese would buy the AIM-9X Sidewinder—the most advanced dogfighting missile—in the U.S. inventory as part of the package.

Loaded for the air superiority mission, a Taiwanese F-16 might be equipped with four AIM-9X Sidewinders and two AIM-120 AMRAAM missiles.

So, in a duel, who would win? Again, like other comparisons, we have to differentiate between the beyond visual range battle and the visual range battle.

In the beyond visual range battle, the J-20 will probably outshoot the F-16. The J-20—at least if the designers are successful—will probably have a formidable combination of stealth, decent radar and very long range missiles. There is a possibility that the F-16’s SABR might be able to detect the J-20 at a fair distance—but the Taiwanese fighter will be hobbled by the AMRAAM missile’s performance in a jamming environment. Armed with PL-15 missiles and cloaked by its stealth, J-20 could theoretically be able to engage the F-16 before the Taiwanese pilot even knows the Soaring Dragon is there.

In the short-range battle the J-20 will probably be less maneuverable. The single-engine F-16 will be more maneuverable, and will have the benefit of AIM-9X Sidewinder missiles. But with the advent of high off-boresight missiles, visual range fights are increasingly becoming mutually assured destruction scenarios.

All of this means that the Republic of China Air Force will have a very difficult time dealing with the J-20. The J-20 will be difficult to detect and would probably be able to engage Taiwanese fighters first. One possible tactic the Republic of China Air Force could use is to use the island’s mountainous terrain to hide their low-flying fighters—potentially denying the J-20 the beyond visual range fight. That’s assuming Chinese look-down shoot-down capabilities are not quite as well developed as Western radars. If Taiwanese low-frequency ground-based radars or if its E-2T Hawkeyes’ UHF-band radar could detect the J-20, they might be able vector F-16s into ambushing the larger mainland planes in more advantageous close-range fights where they might have a chance.

The advanced capabilities of the J-20, concentrated in a single package is a real threat to Taiwan. In the face of a large and increasingly powerful Chinese Air Force, Taiwan will find it increasingly difficult to maintain air superiority over the island. It might be worth it to adopt a bastion-style defensive posture—two can play at the anti-access/area denial game.

Kyle Mizokami is a defense and national security writer based in San Francisco who has appeared in The Diplomat, Foreign Policy, War is Boring and The Daily Beast. In 2009 he cofounded the defense and security blog Japan Security Watch. You can follow him on Twitter:@KyleMizokami.

Image:Flickr/Buddy8d