China is upset with the extent that American ELINT (Electric Intelligence) aircraft, especially the RC-135W, E-8C, and a growing number of UAVs, are operating over the South China Sea and near Chinese naval bases and coastal airbases to monitor Chinese military electronics on land and aboard warships and naval aircraft. The American ELINT aircraft operate outside Chinese territorial waters (22 kilometers from the coast) but within the EEZ (Exclusive Economic Zone) which extends 360 kilometers from the coast.
The Chinse tried to deal with this by shutting down sensitive electronic broadcasts if the Americans were around. The U.S. ELINT aircraft could be tracked via the transponder all large aircraft are supposed to carry and use. The U.S. ELINT responded by using transponder codes for nearby civilian rather than military ones. With this change of code the ELINT aircraft could use airline routes to get close to the Chinese bases, ships or aircraft without risking the Chinese switching off electronics the ELINT aircraft wanted to monitor and analyze.
China now claims that this might be a violation of EEZ use. EEZ rules are covered by an international treaty that China signed but ignores when it is inconvenient. The most glaring example of this is the China claim to ownership of the South China Sea because China has claimed portions of the South China Sea by ignoring existing EEZ portions belonging to the Philippines, Vietnam, Taiwan and several other states. The Chinese claims are invented and the best China can come up with is activities by Chinese fishing boats in centuries past. In addition, China fabricated ancient documents to reinforce their case. An international tribunal examined these claims and declared them false and illegal, at least in the case of the Philippines, which went to court over the matter. China declared the ruling irrelevant but is now threatening to go to the same court to try and declare American use of civilian transponder codes illegal (it isn’t). China also does not want to try and use force because that would risk retaliation and the elimination of its illegal artificial island bases in the South China Sea.
China had, until recently used dangerous aerial harassment by sending fighters to fly dangerously close to American ELINT aircraft. That caused one collision, in 2001, when the Chinese fighter clipped a U.S. Navy EP-3 ELINT aircraft off southern China. The fighter crashed, killing the pilot. The crippled EP-3 made an emergency landing on Hainan where the Chinese took it apart before returning the aircraft and its crew. China accused the EP-3 of causing the collision. The EP-3 is a P-3 ASW (anti-submarine warfare) based on a 1950s four engine turboprop airliner. The lost Chinese jet was faster, more agile and reckless. After this incident Chinese pilots were given secret orders to cut out that sort of recklessness or else.
Since 2001 P-3C has been getting replaced by the P-8 Poseidon, which entered service in 2013 and is based on the widely used Boeing 737 airliner. The Boeing 737 based P-8A is a two-engine jet that has proved superior to the P-3 and there will eventually be an EP-8. The most frequently used ELINT aircraft operating off China are the RC-135W and E-8C that are based on the Boeing 707-200 four-jet airliner. The EP-3 has a harder time trying to pass as an airliner.
China is also having trouble operating its new military aircraft from its illegal South China Sea bases and that is probably a major reason for the current media-based propaganda campaign to justify using aerial harassment or force against foreign ELINT aircraft. The Chinese propaganda also mentions Cold War era Russian use of force against military ELINT aircraft and, in a 1983 incident, a South Korean commercial 747. In all these cases the Russians shot down aircraft and the loss of the 747 was a great embarrassment to Russia. The Russians later claimed that they mistook the 747 for an American 707-based ELINT aircraft that had apparently crossed the flight path of the 747. Blaming the Americans didn’t do much good because after the Soviet Union collapsed in 1991 more details of the 1983 747 loss were revealed. The problem was not a smaller American ELINT aircraft being in the vicinity but Russian ground controllers who feared punishment if they did not order the intruder shot down, even when the fighter pilot reported that the target (747) was too big for an ELINT aircraft. The ground controller persisted and the 747 went down. The Russians began manufacturing excuses because the ground controller wanted to avoid a reprimand for sending interceptors to shoot down, and not just inspect a possible intruder. In the last decade of the Cold War Russian air defenses got sloppy, made a lot of mistakes and word came down from the high command that additional incidents would be punished. That led to incidents of small Western civilian aircraft flying deep into Russia as pranks.
The situation developing in the South China Sea has been going on for over three decades. One of the first Chinese South China Sea military facilities was the Fiery Cross Reef airbase, which occupies most of an artificial South China Sea island that did not exist until the Chinese showed up in the 1980s. The reef was claimed by China in 1987 as China offered to create a small artificial island for a UN program that encouraged the construction and operation of a Marine Observation Station. Taiwan, Vietnam and the Philippines had overlapping EEZ claims on the reef while China did not. Within two decades the Marine Observation Station had expanded into a much larger artificial island and eventually a military base. That base eventually had twelve reinforced concrete hangars for combat aircraft and four larger hangars for aircraft like the Y-8, which is similar to the American C-130 and used for a wide variety of special tasks, like EW (Electronic Warfare), ELINT (Electronic Intelligence Collection), AWACS (aerial warning and control), AEW (early warning) and ASW (anti-submarine warfare). Most of the 150 Y-8s (and slightly longer Y-9s) are still used as transports but over the years at least a third of the Y-8s have been converted to other uses.
In 2017 China stationed four new Y-8Qs, the most advanced model of its ASW (anti-submarine warfare) aircraft, in the south (Hainan Island). This is where China stations warships and naval aircraft that operate throughout the South China Sea. Because of the importance of the sea routes via the South China Sea to the Persian Gulf to the Middle East, Africa and Europe, the Southern Fleet has been growing in size and importance relative to the Northern Fleet and the new Central Fleet up north.
The Y-8Q/FQ is China’s answer to the American P-3C maritime patrol and anti-submarine aircraft. Both aircraft are similar in shape and equipment. While outfitted in a similar fashion it is still unclear how close the Y-8Q is to the P-3C in capability. The first flight of a fully equipped Y-8Q took place in 2012, and apparently the design was being rushed into service. This was when the Americans introduced their jet-powered P-8.
Chinese intelligence specialists warn that using the new ASW and ELINT aircraft around or from South China Sea bases risks having their operational secrets analyzed by the American ELINT aircraft. China is trying to generate some international opposition to the American ELINT efforts. Because China is seen as threat by far more nations than is the United States, that is not working and is making China look bad as they usually use this “justification propaganda” as a prelude to some new misbehavior they are planning.