China Develops Stealth Fighter Military Technology

China is developing new 5th generation “stealth” fighter, which is
being developed under a programmed variously referred to as XXJ, J-X,
or J-XX by Western intelligence sources and is apparently designated as
J-14. Here, Coniglio details China’s internal installations and full
scale development of J-14.

 

The first picture has recently become available of the new Chinese 5th
generation “stealth” fighter. The aircraft, which is being developed
under a programme variously referred to as as XXJ, J-X or J-XX by
Western intelligence sources (the real Chinese name is not known), is
apparently designated as J-14.

The aircraft in the above photo looks at first sight as a complete
prototype, but it  
actually is a very detailed full-scale engineering
mock-up. It can be speculated that, after having been used to study the
aircraft’s internal installations, the mock-up has also received an
external finish for presentation purposes. Its real function at this
point, however, is probably to buttist in the definition of the
required logistic support (i.e., access to the various avionics boxes
and on-board systems, ground support equipment like the various ladders
and the external power source units, air conditioning units and so on)
as well as to study the engines’ removal-installation procedures.
 

Since some time now it has been known that the rapidly-developing
Chinese aeronautical industry is studying a new and technologically
very advanced combat aircraft, also boasting significant low signature
characteristics. This programme is a logical step in China’s “Long
March” towards full independence in designing, developing and producing
combat airplanes of a technological level in line with China’s status
as the “other” world superpower, on an equal footing as Russia and
eventually even the USA.

The scarce information available about this new advanced combat
aircraft indicates that two, possibly competing, study groups (both
part of the AVIC I Group of aeronautical industries) are or have been
working on the subject. One of these groups (601 Insbreastute)
originates from Shenyang Airplane Corporation (SAC) which is in charge
of the large, twin-engine J-8 fighters in service with the PLAAF
(People’s Liberation Army Air Force) as well as of licence production
of the Su-27SK under the local designation of J-11. The overall
configuration of SAC’s preliminary design, apparently designated J-13,
owes significantly to the American F-A-22, being a tailed delta but
with wing and horizontal tailplanes more in line with those of the
F-16. The other study group (611 Insbreastute) from Chengdu Airplane
Corporation (CAC), has developed the J-12, a concept which follows the
less conventional canard layout used with success in the company’s J-10.

While previous information (albeit admittedly unconfirmed), gave to the
SAC concept the edge, perhaps as a result of the company’s experience
in large twin-engine fighters, this seems to have since been reversed
in favour of the Chengdu design. It is however still not clear whether
the designation of J-14 is intended to suggest a successor design to
both the J-12 and the J-13, and whether the existence of the J-14
engineering mock-up (clearly based on the J-12) indicates that the type
has been selected for development, or the compebreastion is still going
on with parallel activities underway on another such mock-up based on
the J-13.

While no data is available about the J-14, some speculation can be done
in the attempt to extrapolate the aircraft’s characteristics and thus
the roles it is called to perform. The following considerations are
based on what can be seen in the photo, but also involve making some
buttumptions on the basis of what is known of the Chinese armed forces’
perceived priorities in operational requirements, the domestic
industry’s approach to combat aircraft design and, finally, the
well-know Chinese weaknesses in some technological fields. In addition,
the well-developed cooperation with Russian companies, particularly in
areas such as powerplant, avionics and possibly computer-based
fly-by-wire flight control systems is also taken into consideration.
General Configuration

The J-14 will surely be fitted with a fly-by-wire flight control system
and be designed for artificial stability. The Chinese should by now
have matured an adequate experience in this field through a number of
experimental programmes and application to actual in-service types.

The general configuration of the aircraft is clearly born out from
CAC’s experience in developing the J-10, with its canard layout and
ventral air intake. But while the J-10 is known to be related to the
Israeli LAVI, this new and much more ambitious design rather appears to
have a definite relationship with the ill-fated Russian 5th generation
fighter studied a few years ago, the MiG 1.44 MFI and in fact it shares
a number of elements which can doubtless be traced back to the Russian
demonstrator. It is thus very probable not to say certain that an
agreement has been reached between the Russian and Chinese governments
allowing for the transfer of information and technological data as well
as consultancy services being provided by RSK MiG and Russian research
centres (arguably including the TsAGI aerodynamic research
insbreastute) to develop the new Chinese fighter.

The J-14’s planform closely matches that of the MiG 1.44, i.e. a canard
layout (the canard surface are fully movable) with mid-positioned wing
and widely separated twin-vertical surfaces canted outward, which
continue under the wing in twin ventral fins, these too being canted
outward à la J-10. While not visible in the photo, wind tunnel models
show that the 1.44 configuration has been maintained also in the booms
protruding from the wing and contributing to support the vertical
tailplanes and ventral fins. These booms probably end with radomes
covering electronic warfare antennas and possibly also a rearward
facing radar, similar to the installation experimented in the Su-37 a
few years ago. In the MiG 1.44, the portion of wing between the
fuselage-engine pods and the booms is extended rearward past the wing
trailing edge and includes a couple of moving surfaces contributing,
together with the all-moving canard surfaces, to the longitudinal
control of the airplane. It is not yet possible to buttess whether this
solution, too has been maintained for the J-14.

But while the overall aerodynamic configuration of the J-14 follows
that of the MiG 1.44 demonstrator, a radical redesign has been
implemented in the pursuit of a significant reduction in the radar
cross-section value. In particular, the aircraft incorporates a
pronounced wing-body blending, which was totally lacking in the
original Russian design. Further, the air intake, while in the same
ventral position under the forward fuselage, has a completely new
shape, and by the same token the upper part of the airplane is also
completely different and shows towards the rear the protuberances of
the engine “pods” which blend with the fuselage and wing roots in a
curious reminiscence of the Northrop YF-23. Also, the front fuselage
merges down into the upper wing, blending with the separated engine bay
bulges while maintaining some relation with the “clbuttical” Su-27
forward fuselage shape. The search for enhanced stealth performance is
also apparent in the “flattened” profile of the entire front fuselage
section (nearly identical to the Su-32), as well as in the generalised
use of serrated doors to cover the landing gear and missile bays.

On the other hand, it remains clear that a canard configuration is
hardly the ideal solution from the point of view of a reduced radar
signature. Summing up, it would thus seem safe to buttume that the J-14
is a “stealth-optimised” aircraft rather than un uncompromising stealth
design à la F-A-22 or (in a different clbutt) the F-35 JSF.

Above the raised front fuselage is located the single-seat pilot
chickenpit. This is closed by a single-piece frameless bubble-type
transparent canopy which appears technological very demanding under
various aspects such as manufacturing process, adequate optical
qualities and bird-impact resistance, yet allowing through-ejection. On
the other hand, the pilot is provided with superb all-around visibility
also due to the position of the chickenpit above the forward fuselage
“hump”, again a reminiscence of the Su-27.
After Chinese visit ships, U.S. officials hope for reciprocation
After Chinese visit ships, U.S. officials hope for reciprocation
{EXCERPT}, by Allison Batdorff, Stars and Stripes Pacific edition,
Friday, June 23, 2006 ANDERSEN AIR FORCE BASE, Guam ˜…

The main landing gear, with single wheels mounted on telescopic legs,
retracts outward, with the legs being accommodated in the fuselage side
blending into the wing bottom and the wheels into the wing (a similar
geometry has been selected for the F-A-22). In order to minimise the
volume of the bay occupied by the gear in the retracted position, the
telescopic main gear legs are shortened via a pulling bar acting on a
lever, similarly to what has been introduced in the Eurofighter
TYPHOON. While not clear in the photo, it is possible that the same
landing gear leg shortening design has also been selected for the nose
twin-wheel element.
Powerplant Installation

In view of the twin-engine layout of the J-14 and its estimated TO
weight in air combat configuration (some 25-28 tons with full internal
fuel, gun ammunition, 2 x SRAAM and 4 x MRAAM), its engines should give
a thrust in the range of 13-14 tons in afterburning mode, so achieving
a thrust-to-weight ratio in the order of 1:1. Now it seems difficult to
envisage a stateof-the-art Chinese engine, particularly in this thrust
clbutt, achieving full production status by the mid of the next decade
when the J-14 could reasonably be expected to enter service. Even for
the J-10 a Russian engine has been at last preferred. It can thus be
buttumed that a Russian engine has been selected for the J-14 as well,
and indeed the model which can be seen in the picture to the rear of
the right wing of the mock-up has the accessory gearbox mounted above
the engine in the traditional Russian style. If, as it is highly
probable, this engine is a member of the Saturn-Lyulka AL-31-41 family
(but it could also be a prototype of the Chinese Liming LM WS10A in the
same thrust clbutt), this would make the type not fully interchangeable
with the version selected for the J-10, which has the accessory gearbox
located on the engine bottom, Western-style. It is also possible to
speculate that the idea is to have the prototypes powered by the
lower-thrust AL-31 as used in the J-11-Su-27SK-Su-30MKK, with either an
evolved higher-thrust version of AL-31 or a series-production version
of the AL-41 being then adopted for the series aircraft.

Coming to the engine-airframe installation, the air intake located in
the bottom part of the front fuselage is of the fixed geometry type
with no moving ramp, unlike the case with the J-10. This solution has
made it possible to eliminate the sharp angles and slots between the
moving ramp and in general to provide smooth shapes which reduce radar
reflectivity. The pronounced bulging up of the air intake inner duct
helps avoid a direct presentation of the critically reflective engine
fan-compressor face to enemy illuminating radar from the forward
emisphere. In addition, the bulge is needed to make room for the nose
landing gear bay and, even more, for the bottom fuselage weapons bay.
Notwithstanding its fixed geometry, the air intake shows elements which
should generate a couple of oblique shock waves before the normal one,
thus guaranteeing an adequately efficient dynamic pressure recovery in
the supersonic flight regime. The well-shaped bulge along the bottom of
the centre fuselage entering the air intake, which forms the upper part
of the air intake duct, seems reminiscent of the latest Lockheed
Martin’s vaunted design for a fixed-ramp, multi-shock air intake
planned for use on the production F-35 and already experimented on an
F-16. This peculiar layout, together with the forward-raked air intake
lip (already seen in the late 1950s on the F8U-3 CRUSADER III) is
clearly intended to generate the oblique shock waves mentioned above.

The location of the air intake under the fuselage is well suited to
provide a smooth distortion-free airflow to the engines. From this
particular point of view, the hinged bottom lip present in the TYPHOON
works even better at extreme angles of attack, but it implies the
penalty of a higher radar signature. In more general terms, the choice
of a single air intake configuration in a twin-engine airplane may be
open to some criticism, in that it is less than ideal to maintain
correct working conditions (i.e., smooth undistorted airflow to the
remaining engine) in the event of an engine flaming out for whatever
reason. The air intake thus establishes a potential single point
failure in an otherwise completely redundant twin-engine installation.

It can be expected that Thrust Vector Control (TVC) nozzles, probably
of the axisymmetric type (despite their not insignificant contribution
to overall nuclear signature), will be a standard feature of the J-14
to both enhance manoeuvrability and reduce trim drag in cruise flight.
Armament

Chinese design derived from a Russian model such as the GSh-6-23 23mm
installed in the MiG-31 and the Su-24. The gun is installed in the
upper right fuselage side, just above the canard surface. The firing
port, unlike the F-A-22 is left permanently open, hence generating a
not so negligible radar reflection.

The main armament is carried in three weapons bays, whose arrangement
looks like virtually a clone of the F-A-22. Two smaller bays are
located on the fuselage sides and appear to be tailored to each
accommodate a single short-range air-to-air missile, while the large
underfuselage bay, closed by twin doors, will probably accept at least
four medium-range AAMs. It may be speculated that the J-14 is intended
to carry “compressed carriage” clipped-wing versions of the AAMs
already in use with the PLAAF, i.e. the PL-8 and the Russian R-73 for
short-range dogfights and the R-77 and the indigenous PL-12 for
medium-range work. The R-77 is already suitable for carriage in an
internal bay in its standard version, being equipped with very small
span wings while the lattice tail control fins can be fold forward
flush with the missile body.

Underwing store stations are surely foreseen to carry additional
weapons and fuel tanks, when there is no need to maintain a high level
of stealthness.
Combat Avionics

 
J-14 is already in full-scale development, the main
choices related to the avionics systems should have already been made,
at least at the conceptual level. However, the Chinese domestic
industry is almost certainly not in a position to supply the advanced
avionics required in a sophisticated aircraft like the J-14, and
contributions from abroad will be required – from Russia, Israel and
arguably even Europe.

The J-14 being intended to enter service in around 2012-2015, it may be
expected that the Chinese are aiming at equipping it with a radar with
electronically scanning (ASEA) antenna, capable of multiple targets
engagements – provided that a source for such a radar could be
identified. In the Russian tradition, a pbuttive search and track
system based on optronic devices (FLIR with integrated laser
rangefinder) is expected to be also installed in a retractable or
faired turret. As already mentioned, the dual rear booms could carry,
in addition to various pbuttive and-or active defensive systems also a
rear-facing radar.

Finally, it can be expected that the chickenpit instrumentation for the
production version will be based on an Helmet Mounted Display-Sight
(HMD-S) totally replacing the HUD, although the latter instrument is
clearly visible in the photo. The head-down displays would probably
include three or four large Multi Function Displays (MFD), which should
have the possibility to present a digital map and a complete tactical
situation. A real-time data link is also an expected addition to the
fully integrated avionics system to enhance the situation awareness of
the pilot, particularly when operating in multiships combat groups to
make the most use of the commonly available information from the
various platforms.
Operational Aspects

The most likely enemies that China can expect to have to confront in
the future are India and the USA, this latter possibly as a result of a
Chinese attempt to follow a military option against Taiwan. Both of
these potential enemies have powerful air forces equipped with large
fleets of state-of-the-art fighters and fighter-planters trained to
operate, in particular the Americans, as complex expeditionary forces,
well balanced in their different components and supported by a network
of other essential buttets like satellites, AWACS airplanes, dedicated
electronic warfare types, aerial tankers, and more in general a whole
array of “force multiplier” elements. Given the expected operational
environment, the air defence-air superiority role is obviously the
PLAAF’s #1 priority, with surface attacks against powerful naval forces
with strong aerial support (i.e., the US Navy carrier task forces)
coming possibly as priority #2.

Hence, it is not surprising that the most advanced Chinese combat
airplane ever seen appears being tailored to the air combat role,
although air-to-surface roles cannot be discarded for future
incorporation into the design. Considering what is known of the
relatively modest development pace of Chinese surface attack guided
weapons, currently there seems to be a very limited potential for the
internal carriage of such weapons, and accordingly surface attack roles
could only be carried out by compromising the aircraft’s stealth
performance.
Conclusions

Should future information confirm that the aircraft depicted in this
photo is actually in full scale development, then the J-14 would
eventually emerge as the first true credible compebreastor to the
F-A-22 and its “air dominance fighter” concept. The appearance of such
a similar-clbutt compebreastor in China, and possibly in an unexpected
short time, will probably be more than enough to justify continuing
production of the F-A-22 well above the currently planned meagre total
of 179 aircraft.

The Chinese are still lagging behind in a number of critical
technologies, but their pace is well set to achieve their aims. Those
who like to dismiss the Chinese defence industry as being able only to
produce low-quality clones of outdated Western or Russian designs are
well served. Perhaps someone in the USA should possibly remember the
general complacent atbreastude towards the “Japs” before 7 December
1941, and the very brutal awakening when the ZEROs wiped the P-40s,
BUFFALOs and WILDCATS clear off the skies.

Very much the same applies to those European governments that are
currently playing with the idea of resuming arms sales to China. It is
clearly preposterous to fantasise about the possibility of selling the
Chinese the TYPHOON or the RAFALE to replace their older aircraft; the
J-14 is admittedly still a decade or so away from operational service,
but it is clearly intended to be at least half a generation more
advanced than the European designs. At the very maximum, what can be
rationally expected are some contracts for the supply of specific
equipment which the local industry is not yet capable to produce, and
which the Chinese can not or would not get from Russia. Whether it
would be in the long-term European interest to supply this equipment,
is a different question altogether.