It was recently revealed that in April a Russian Su-27 fighter buzzed an American RC-135 signals (electronic) reconnaissance aircraft off the Pacific coast of Russia. Without making radio contact the Su-27 flew within 30 meters (100 feet) of the RC-135 while both were in international airspace. After approaching the RC-135 several times the Su-27 flew off. The U.S. complained to Russia but got no response but those in the intelligence community saw what was going on.
The RC-135 is a flying vacuum cleaner of electronic signals. Built on the same airframe as the KC-135 tanker and Boeing 707 airliner, it carries two dozen people who operate all the electronic gear. Exactly what kind of electronic signals the RC-135 can pick up is classified but apparently includes any electronic device Russia, China or Islamic terrorists have.
Recon flights over international waters off the coasts of hostile (or potentially hostile) nations had been going on since the end of World War II. Early in the Cold War American recon aircraft were often attacked by the Russians and several were lost. But by the 1960s things had calmed down and in 1972, the U.S. and Russia signed an agreement to cover encounters at sea with the understanding that both sides would refrain from mischief in the air as well. Russian and Chinese electronic reconnaissance ships still cruise off American coats and the Americans, and several other countries reciprocate.
Until early 2001 there were no more serious problems with harassment of ships or airborne electronic reconnaissance operations. Then China began regularly violating that decades long “understanding”. The most blatant violation occurred during early 2001 when Chinese fighters regularly harassed U.S. reconnaissance aircraft off the coast of China. Then on April 1st 2001, a Chinese J-8 twin engine fighter clipped a U.S. EP-3 four engine turboprop aircraft. The J-8 crashed and the pilot ejected (but was never found.) The EP-3 limped away and made an emergency landing at a Chinese military airfield on nearby Hainan Island.
Suddenly buzzing foreign recon aircraft had ceased to be is a no-no. This caused all sorts of bad feelings. This was especially the case when nimble jet fighters harass slower and larger recon aircraft. International conventions stipulate that the smaller, faster aircraft must stay clear of larger slower planes. That doesn't prevent you from intercepting and escorting aircraft flying off your coasts outside your territory. What apparently happened between the J-8 and the EP-3 was a second rate pilot (the Chinese now have more modern Russian aircraft for their best pilots) coming up behind the EP-3 and finding out too late about how troublesome the air turbulence larger aircraft leave behind them can be. The J-8 is generally recognized as a pig of an aircraft and hard to control.
The Chinese also put themselves in an embarrassing position with the international aviation community by accusing the EP-3 of causing the accident. Aside from the physical impossibility of that, EP-3 pilots are selected for their calm demeanor, not suicidal tendencies. Moreover, the EP-3 pilot’s primary task is to fly the aircraft along a precisely defined route (to get the best reception and to make sure the aircraft stays in international air space), not play games with fighter jets.
One reason China and Russia want to keep American aircraft (especially the U.S. Navy EP-3 and the U.S. Air Force RC-135) away from their coasts is because these flights analyze air defense systems and any other electronic systems being used by nearby aircraft, ships or even ground units operating near the coast. By carefully studying these transmissions from international waters (at least 22 kilometers from the coast) vulnerabilities can be discovered that can be exploited in wartime, or in peacetime for further espionage.
As China and Russia develop more powerful electronic devices they are apparently determined to keep the details secret so their electronic wonders will not be easily defeated in wartime. To that end, China has requested that the United States eliminate the use of aircraft and ships to perform electronic surveillance along the Chinese coast, even in international air space. The U.S. recon operations always take place in international air and sea space but the Chinese know that this does not stop the Americans from picking up lots of useful information. China has implied that if the U.S. does not cease this snooping, there will be more confrontations with Chinese aircraft and ships. Russia is now resuming the aggression it demonstrated early in the Cold War until the “ceasefire” agreement was achieved in the early 1970s.
The EP-3 and RC-135 are getting old and will eventually be replaced by UAVs but for the moment they are the best tool the U.S. has for sniffing out things like gaps or vulnerabilities in a potential enemies electronic systems. The main reason for all that popularity is that the EP-3s and RC-135s are very good at what they do and have been much in demand since September 11, 2001. With the withdrawal of American forces from Iraq and Afghanistan more U.S. electronic recon aircraft are available for duty along the Chinese and Russian coasts.