Saturday ITAR-TASS printed an interesting update on the PAK FA engine story. It doesn’t really clarify anything (actually quite the opposite), but it’s part of the story.
Recall last spring the engine designers were saying developing a “second phase” engine for PAK-FA could take another 5-6 years, while Sukhoy was saying it might be 10-12 years. In what follows below, the engines aren’t specifically identified as “second phase,” but they are called “seriously distinct from the 117S.”
General Designer of the A. M. Lyulka Scientific-Technical Center (a Moscow subsidiary of NPO Saturn) Yevgeniy Marchukov claims the construction of an engine for the fifth generation fighter is going successfully, and it will go into serial production.
The second experimental T-50 reportedly took off with this engine on 3 March.
“The engines in the experimental prototypes of the future Russian fifth generation fighter are seriously distinct from the 117S engines intended for Su-35 aircraft, both in their parameters and in their fundamentally new automated control system. The T-50 aircraft with NPO Saturn engines fully corresponds to the tactical-technical requirements for the aircraft. And with these engines produced serially, the PAK FA will be supplied for the needs of the Russian Air Forces.”
For his part, Saturn managing director Ilya Fedorov noted that the enterprise “supported the takeoff of the aircraft in the necessary time,” just as it was ready for flight.
ITAR-TASS goes on to add that special stand tests and service life tests on the engine continue at the Lytkarinskiy Machinebuilding Plant (another Saturn subsidiary). Ground development is being conducted on the T-50-KNS model with aircraft systems from OKB Sukhoy at the Gromov Flight Test Institute. Flight tests are also ongoing. T-50-1 has more than 40 flights, the T-50-2 two flights, and the Su-27 flying laboratory has 32 flights.
This last story fits well with a release made about 6 months ago by one of the Senior people involved in the Engine Development for the Pak Fa. I can’t remember who?
In brief he said they now have 2 fifth generation engines more or less proven. The ultimate engine was still being developed. The type 117 used on the protoypes and  I think it was called the Type 30 with 10% better thrust than the 117 and had been tested on the Pak Fa. It read as if all it needed was more testing and proving up. [probably a further development of the 117]. The ultimate Type 129 mentioned would have about 15% more thrust again and probably would not be ready before 2018 being a new engine. Some say this will be a variable bypass engine and of similar size and weight to the 117. Maybe it will have better stealth cowlings etc. If they can get a variable bypass engine down to that size and weight it will be more like a 6th Gen Engine. If it is that advanced Sukoi is probably correct in being a bit pessimistic about when it will be ready.
The type 30 will be ready in 2015 he said – it should be if it has already been tested on the Pak Fa. I don’t think they would risk putting an experimental engine on a valuable prototype.
I think other readers will get a lot out of your comments. Your humble author doesn’t know a whole lot about the tech details; he just tries to unearth info and debates in the vernacular. Thanks for reading.