State of Aerospace Engine for China’s PLA

The issue of finding adequate and reliable engine has always been an
issue for china’s PLA. The navy seems to be getting by with license building
advanced diesel engines, which are not under embargo, for most of its
ships and some copied or home developed gas turbines for shipping class
that need them. The air force has always seen delays due to problems in
local production of engines for a series or waiting for Russian engine
options. Shenyang AC has been quite unfortunate in having 2 of its
recent aircraft programs (J-8F and J-11B) delayed due to issues with
production of a new class domestic engine. I’ve talked in the past about
the state of engine production in China, but was overly optimistic over
the program in those cases. So, this entry will attempt to look at
some of the domestic engine programs and their import programs.

FWS-10 Turbofan Engine

First, the FWS-10 program is probably the most relevant to the current
well being of PLA. We are at a point where all the recent J-11Bs have
been produced with FWS-10 along with J-15S and J-16. I’m sure they are
still working through problems with a new engine like FWS-10, but it’s
no longer problematic like early 2011, when SAC had many J-11Bs without
engine seating out in its airfields. At that time, the Chinese air
force simply refused to take those aircraft because issues with FWS-10.
By this point, Russians were more careful about making sure their
AL-31F
did not end up on J-11B, so the project was basically on hold
after that first regiment of J-11B join service with AL-31F. By now, we
have seen 4 more J-11B regiments with PLAAF and 3 more J-11B regiments
with PLANAF. Assuming that all of these regiments become full at some
point this year, that would be approximately 7 x 24 = 168 J-11B/BS in
service with FWS-10. Including the J-15/16 prototypes that SAC is
building every year, I would guess easily 30 to 40 flankers are produced
every year using FWS-10 as power plant. Assuming that a spare is
produced for every 2 engines, the yearly production of FWS-10 could be
over 100 at this point. So the question is why they are still using
AL-31FN on J-10B and AL-31F on J-15. I think at this point they are
developing a naval version of FWS-10 to last through the wear and tear
of naval operation. At the same time, a higher thrust version is
required to support the added take-off weight on J-16. Future flankers
will continue to use WS-10 series. A J-10B prototype with FWS-10A is
probably still being tested, but it would probably have to match the
performance of AL-31FN series 3 (1000 ton more thrust than base layer)
in order to be equipped on J-10B production batches. Also, the current
J-20 prototypes are also most likely using AL-31FN series 3 engines. As
we move forward, this version of AL-31FN is certainly not a viable
option for production version of J-20. China can choose a later AL-31FN
series that would be equivalent to AL-31FM2 or FM3, which would have
comparable or more power than 117S engine that are used on Su-35 right
now. If the upgraded variant of FWS-10 goes into production, that could
be used in both J-20 or future batches of J-10B. So I would think the
first few years of J-20 production (maybe 2 regiments) will be using
underpowered engines (140 to 150 kN range with afterburner) and then
WS-15 will go into production. Back in 2010, one of the few good
Chinese sources on engines mentioned that WS-15 was probably 10 years
from mass production based on where the program was at. Articles on
WS-15 are hard to come by, but my guess is that they will start to test
it out on fighter jet in a couple of years. After that, it will be a
waiting game for certification.


The other major question is the status of the WS-13 program.
Speculations over this program has been ongoing since JF-17 first went
into production. Recently, a second batch of 100 RD-93 was signed with
Russia. That would indicate continuing delays in the WS-13 program. At
the same time, there was news in the middle of 2014 that Guizhou Liyang
was putting significant investment into building a production line for
WS-13. We know that RD-93 has been used on FC-31 technology
demonstrator and also the Lijian UCAV technology demonstrator, but the
vast majority of second batch of RD-93s are still allocated for JF-17.
At some point, they will have to test out WS-13 with a batch of
production JF-17s. It’s possible that a portion of this second order
will be used as spares/replacement, but the size of the RD-93 is
confusing given the report of WS-13 production line. Going forward,
I’ve talked about how FC-31 does not currently have a viable option for
engine. It looks like an improved variant of RD-93, RD-93MA, is under
development. When they do choose to move forward with the FC-31
project, I think the current solution of baseline RD-93 (or even WS-13)
is too underpowered for even the pre-production batch. So in order to
really go forward in FC-31, they have to use RD-93MA before the new 9500
kgf engine under development becomes ready sometimes in the next
decade. WS-15 project has higher priority, so that will become ready
first.

For the Y-20 project, the early prototypes are all using D-30KP2. D-30
is also used on the 2 regiment of H-6K (about 40 in total) that have
recently joined service. A few years ago, it was speculated that a
domestic variant of D-30KP2 (WS-18) was getting developed for Y-20 while
the more advanced WS-20 engine was still getting ready. China’s IL-76
engine testbed has been doing flight testing of WS-20 since 2013. Most
recently, they just started doing flight testing of WS-18 on a separate
IL-76 testbed. It seems strange rather the older WS-18 begins flight
testing over a year after WS-20, but maybe this is aimed for H-6K
bombers. Production version of Y-20 is likely to appear sometimes this
year or the next, so they will be using the rather old D-30KP2 engine.
It doesn’t look like PLA is interested in the more advanced PS-90A or
even D-30KP3, so Y-20 will be underpowered for a while. At this point,
even a D-30KP2 powered Y-20 would be a force multiplier for PLAAF.

Turboshaft engines are not very heavily followed by PLA followers. As
late as 10 years ago, issues with producing engine and other subsystems
prevented mass production of the domestic helicopters. More recently,
helicopter production has been increasing for both PLA and civilian
ministries. Since upgraded variant of WZ-6 became available for the Z-8
series, Z-8 production has really taken off for all 3 arms. More
recently, Z-18, military version of AC313, using WZ-6C engine is now in
mass production for the navy and also the army. We have seen the new
Z-18A used in the high altitude of Tibet, which shows how much
improvement have been made for WZ-6C. If Huitong’s figure of 1300 kw is
accurate (and it seems to understated based on other sources), WZ-6C is
competitive with PT6B-67A (around 1400 kw) slated for AC313. At the
same time, production of Z-10 and Z-19 project have both been going
pretty well and look to be sufficiently powered. It seems like
production and usage of WZ-9 engine for Z-10 project has been going
well. WZ-8 production for Z-9/Z-19 helicopters have been going well
too. WZ-16 engine is been developed with France to power Z-15. It may
or may not be usable in the future for other Chinese helicopters like
Z-10. It seems like they have been able to develop upgraded variants of
existing engines either by themselves or with the help of European
companies. The only major remaining project that depends on the
development of a new engine is Z-20. That is quite a huge improvement
for China’s engine industry.

Finally, there are some other engines been developed (either new project
or copying Russian/Ukrainian engines) for UAVs, missiles and trainer
projects. They get much less news, but we do see their appearance
sometimes in Zhuhai air show. Very recently, we saw Chengfa finish
development on one of those projects. So, this is a rundown on China’s
engine developments. Similar to 5 years ago, this area remains the
achilles heel for the Chinese military industrial complex. 
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