wow, a few things:
601 - SAC
611 - CAC
1. In the past, I read plenty of reports that 601 won the competition to be the developer of J-XX. And, I even showed the JDW article that stated J-XX went into wind tunnel testing. From that, I calculated using J-10's experience that J-XX will be flying by 2008 and in service by 2015.
Many of the Chinese sites had sections like this:
An F-22 style wind turrel model of XXJ was showned briefly in an AVIC I promotional video at the 2002 Zhuhai Airshow. First disclosed by US Office of Naval Intellegence (ONI) in 1997, XXJ is a 4th generation fighter to enter the service around 2015. Both CAC/611 Institute and SAC/601 Institute are working their own designs for a twin-engine multi-role fighter with enhanced stealth capability and maneuverability comparable to American F/A-22. It was speculated that 601 Institute has been working on designs based on conventional layout (J-13?) while 611 Institute has been working on designs based on canard/tailless delta wing (J-12?) plus belly air intake layout since early 90s.
According to the reports of the Jane's Defence Weekly, China has already launched its next generation stealthy fighter aircraft programme, and Shenyang Aircraft Industry Co. (SAC) has been selected to head research and development of a new fighter for the PLA Air Force (PLAAF).
2. Now, a couple of things happened recently. The most important of which seems to be that the original news regarding 601 winning the contract for J-XX seems to not be entirely true. The Chinese boards mentionned that the 5th generation proposals are only being decided in April. This post here was a Q&A with Yang Wei (president of 611) in March
He basically answered in the last quesiton that both 601 and 611 have forwarded their proposals. Maybe, the proposals have been decided, maybe not. So, they are basically doing something like the Americans with F-22 and YF-23 by competing firms. (or X-32 and X-35 for JSF)
Also, J-XX might not be just one plane. China could easily create a hi-lo combination like F-22/F-35. It has long been speculated that 601 will get the project to develop something in the F-22 class due to its experience with heavy fighters (su-27). At the same time, 611's experience with J-10 means that it will be more suitable for the medium sized fighter. The question is whether or not the medium sized fighter by 611 is a highly upgraded version of J-10 or a new design using experience from J-10/FC-1.
If you look at the JSF project:
1. 1993-1995, seems to be the initial phase of the project
2. 1996, decided that Boeing and LM are asked to submit competing proposals, basically they are to compete for JSF
3. 2001, LM is selected for JSF
4. 2006, the first prototype rolls out and expected to fly in the fall
5. 2011, expected to be in service
That's 5 years from when the selection is done to the flight and then another 5 years to enter service.
If CAC and SAC really did just submit their proposals at the beginning of this year for the hi and lo 5th generation planes and the selections are done this month, I don't see why the first prototype can take off in 5 years and why it can't join service 5 years from then.
Let's face it, China is no longer at the level it was in 1986 when CAC was selected for J-10. Back then, projects were getting cancelled left, right and center. Then, it had to leap 2 generations with J-10 from J-7. At the same time, it got help from the Israelis, but then found out the engine wasn't available, so it had to redesign. And then, a lot of the technologies like FBW, glass cockpit and such just weren't ready. Even with that, you still went from the first flight in 1998 to getting certified in 2003/4.
From the above, that's how I got the assessment that Yang Wei's reference to J-10's next generation fighter is actually the medium sized 5th generation plane. Also, you may have read that J-10B was started in 2000, first flied in 2003 and got certified in 2005. I'm pretty sure the modified J-10 project started a while back, so I would think it's developmental timeframe should be similar to that of J-10B. I mean, you just need to take a look at how long it took CAC to go from prototype 01 to 04 of JF-17 (pushed IOC back by 2 years?). I would expect similar level of change in the modified J-10, so I find it extremely unlikely that it will take another 5 years before modified J-10 can fly off.
As for the issue of single/twin engine, it seems like pla has decided that the Chinese/Russian engine are just not reliable enough for the 5th generation. When J-10 started, you have to remember that China was not under any kind of embargo and it basically got a lot of help from the Lavi project. So, it's natural that it would follow the Lavi design of using one engine.
