That being said, Russia, China and others are developing advanced UHF and VHF band early warning radars that use even longer wavelengths in an effort to cue their other sensors and give their fighters some idea of where an adversary stealth aircraft might be coming from. But the problem with VHF and UHF band radars is that with long wavelengths come large radar resolution cells. That means that contacts are not tracked with the required level of fidelity to guide a weapon onto a target.
As one U.S. Navy officer rhetorically asked, “Does the mission require a cloaking device or is it OK if the threat sees it but can’t do anything about it?”
http://warisboring.com/articles/how-to-detect-a-stealth-figh...
Depends on the mission. And if full stealth is not necessary after all, why have such an expensive stealth system in the first place?
F-117 and B-2 were attempts at making an actual stealth fighter (completely radar neutral) and even an F-117 was shot down by a Isayev S-125 in 1999. I'd imagine China has at least access to that level of technology.
There's also work on infrared detection and optical detection which weren't possible way-back-when, but with access it inexpensive compute power, might now be a viable way to track even a radar neutral aircraft.
All I am saying it, I believe them, but I am also unsurprised. Against a nation like China I wouldn't even trust the B-2 Spirit to remain immune from interceptors, let alone the F-22, and frankly if China and the US ever went to war drones and missiles would likely play a greater role than manned fighters.
Please pardon my bit of chuckling, but in the past Chinese Air Force pilots can't even intercept a prop-plane without hitting the thing. An F-22? Going to need a lot of practice.
It's nice they can see the F-22 though. It didn't really help in the Middle East that much[1] years ago with the SR-71. But it's something to feed the press!
[1] http://www.airlinepilotforums.com/cargo/19456-fantastic-sr-7...
Meh.
Plus, its a plane, with a big ass engine, flying through the sky at hundreds of miles per hour. There should be other ways to detect the damn things.