Recently Chinese Chengdu J-10 fighters tailed  two Japanese Boeing F-15 that were trailing a Shaanxi Y-8 patrolling near what Tokyo calls the Senkaku and Beijing the Diaoyu islands.

Contrary to popular perception Japan has a stronger air force, despite significant strides of Chinese air force recently managed to achieve. Currently China has 500 advanced fighters, that include 200 single-engined J-10s and about 270 Shenyang J-11s and Sukhoi Su-27s. China also has some older aircrafts like 400 J-7s: a license-built version of the Mikoyan-Gurevich MiG-21. Apart from this according to unconfirmed reports J-7s can be remotely controlled, making them into cruise missiles of sorts.

Against this though the Japanese Air Self-Defence Force operates fewer aircrafts, includeing 153 F-15J fighters, 63 Mitsubishi F-2As, apart from about 80 McDonnell Douglas F-4 Phantoms, given the untested and relatively less advanced Chinese technology would find it hard to maintain its aerial superiority, over the disputed area.

Japan’s Air Self Defense Force has formed a monitoring network, comprised of scouts, satellites, early warning aircraft and ground-based radar.

The air self-defense force has the largest number of airborne early warning aircraft in Asia. This includes thirteen E-2C hawkeyes and four E-676 early warning aircraft bought from the US. Their main aircraft are the US F15 fighter and F2 fighter.

Meanwhile, it also has four KC-767 tanker airplanes, with a maximum oil supply volume of nearly 100 tons. According to Japan’s defense ministry, it will buy eight F-35A aircraft from the US before March 2015.

“In short, Japan has a significant edge,” says Oriana Mastro, a fellow at the Center for a New American Security think tank. “But the Chinese can create challenges for Japan to maintain aerial superiority.”

One challenge facing Japan, she feels, is its ability to provide constant surveillance of the disputed islands. As Chinese naval and aircraft activities become more routine, it will become harder for Tokyo to determine Beijing’s intentions.

Indeed, Tokyo has identified persistent surveillance as a priority area. “The current mid-term defence programme [from March 2011 to March 2015] takes drones into consideration as part of the study on warning and surveillance posture around our country,” Japan’s defence ministry said in an email to Flightglobal.

“We will further study the efficiency and operational role of drones, the comparison of the cost-effectiveness with existing equipment [and] offsettability, and take into account technological trends.”

Although Tokyo declines to mention specific programmes, unsourced media reports have suggested that it is interested in the Northrop Grumman RQ-4N Broad Area Maritime Surveillance variant of the Global Hawk, being developed for the US Navy.

Another regional defence expert feels that Beijing would be at a significant disadvantage in any shooting war over the islands.

“They can fly a few J-10s out and perhaps fly alongside Japanese F-15s, but could they sustainably project power that far out from the mainland over an extended period?” he asks. “China only has limited experience using its [Xian] H-6 as tankers.” Tokyo, by contrast, can call on a four-strong fleet of Boeing KC-767s.

Another area where Beijing is weak is in airborne early warning and control (AEW&C). Its new force of Y-8-based KJ-200 and adapted Ilyushin Il-76 KJ-2000 platforms are untested, while Japan has four recently upgraded E-767 AEW&C aircraft (below) and 13 Northrop E-2C Hawkeyes.

“In a conflict Japan would have far better situational awareness,” the source says. “Also, Japanese pilots are able to operate autonomously of ground control, but Chinese fighters would likely operate under GCI [ground controlled interception].”

Mastro feels that the current tensions will not greatly change long-term procurement trends, with both China and Japan to continue to build their air power capabilities. The key is for the USA and its Pacific ally to make the right procurement choices now, she says, so as to offer a capable deterrent to China 20 years from now.

“The trajectory is what concerns the USA,” Mastro says. “China can create challenges without catching up, and they don’t need to catch up to achieve political victories. With air power tipping in China’s favour, [Beijing] may be more inclined to use force.”