May 21, 2007: Chinese J-10 fighters have been spotted porting a satellite antennae behind the cockpit. This could either be for satellite communication (SatCom) or, more likely, satellite navigation. Either way, it's possibly using the Chinese satellite navigation system called BeiDou. Think of this system as GPS light. BeiDou only covers East Asia, and not even all of China. But it covers the areas along the coast, and Taiwan. The BeiDou system is less accurate than GPS, slower, but it does allow two way traffic. This is useful for sending short messages (up to 120 Chinese characters so, about a hundred words). Sort of IM (Instant Messaging) class stuff. The system can only handle a few hundred thousand users, but that would be sufficient for the number of Chinese troops involved in any major operation. BeiDou also suffers some reliability problems, and is apparently very vulnerable to jamming and spoofing. Because of all that, it is believed that BeiDou is just a first generation system. A training system, one where China learns the ins and outs of building satellite navigation systems.

The J10 is also Chinese made. It looks something like the American F-16, and weighs about the same (19 tons). Like the F-16, and unlike the Su-27, the J10 has only one engine. Originally, the J10 used a Russian AL-31FN engine, but China has been working for a decade to manufacture their own version of this, the WS10A. It's no accident that the J10 resembles the F-16, because Israel apparently sold them technology for the Israeli Lavi jet fighter. Israel abandoned the Lavi project, because of the high cost and availability of cheaper alternatives (buying F-16s and F-15s from the United States.) But the Lavi was meant to be a super F-16, and incorporated a lot of design ideas from the F-16 (which the Israelis were very familiar with, as they used them, and had developed new components for them.)