https://en.wikipedia.org/wiki/Chengdu_J-20
The Chengdu J-20 (simplified Chinese: ?-20; traditional Chinese: ?-20) is a
single-seat, twinjet, all-weather, stealth fifth-generation fighter aircraft
developed by China's Chengdu Aerospace Corporation for the People's Liberation
Army Air Force (PLAAF). The J-20 made its maiden flight on 11 January 2011, but
the plane was officially revealed on China International Aviation & Aerospace
Exhibition in 2016. In March 2017, Chinese media reported that the aircraft has
entered initial operational capability phase with limited service within Air
Force.
The J-20 descends from the J-XX program in the 1990s, J-20 is designed to become
an air superiority fighter with precision strike capability. In September 2017,
the J-20 officially entered military service with PLAAF, becoming the third
operational fifth-generation stealth fighter aircraft in the world, and the
first in Asia.
The J-20 has a long and wide fuselage, with a chiseled nose section and a
frameless canopy. Immediately behind the cockpit are low observable intakes.
All-moving canard surfaces with pronounced dihedral are placed behind the
intakes, followed by leading edge extensions merging into the delta wing with
forward-swept trailing edges. The aft section has twin outward canted all-moving
fins, short but deep ventral strakes, and conventional round engine exhausts.
One important design criterion for the J-20 is high instability. This requires
sustained pitch authority at a high angle of attack, in which a conventional
tail-plane would lose effectiveness due to stalling. On the other hand, a canard
can deflect opposite to the angle of attack, avoiding stall and thereby
maintaining control. A canard design is also known to provide good supersonic
performance, excellent supersonic and transonic turn performance, and improved
short-field landing performance compared to the conventional delta wing design.
Leading edge extensions and body lift are incorporated to enhance performance in
a canard layout. This combination is said by the designer to generate 1.2 times
the lift of an ordinary canard delta, and 1.8 times more lift than an equivalent
sized pure delta configuration. The designer claims such a combination allows
the use of a smaller wing, reducing supersonic drag without compromising
transonic lift-to-drag characteristics that are crucial to the aircraft's turn
performance.
The main weapon bay is capable of housing both short and long-range air-to-air
weapon bays behind the air inlets are intended for short-range AAMs (PL-10).
These bays allow closure of the bay doors prior to firing the missile, thus
enhancing stealth.
Analysts noted that the J-20's nose and canopy use a similar stealth shaping
design as the F-22, yielding similar signature performance in a mature design at
the front, while the aircraft's side and axi-symmetric engine nozzles may expose
the aircraft to radar. One prototype has been powered by WS-10G engines equipped
with different jagged-edge nozzles and tiles for greater stealth.
Others have raised doubts about the use of canards on a low-observable design,
stating that canards would guarantee radar detection and a compromise of
stealth. However, canards and low-observability are not mutually exclusive
designs. Northrop Grumman's proposal for the U.S. Navy's Advanced Tactical
Fighter (ATF) incorporated canards on a stealthy airframe. Lockheed Martin
employed canards on a stealth airframe for the Joint Advanced Strike Technology
(JAST) program during early development before dropping them due to
complications with aircraft carrier recovery. McDonnell Douglas and NASA's X-36
featured canards and was considered to be extremely stealthy.
Radar cross-section can be further reduced by controlling canard deflection
through flight control software, as is done on the Eurofighter.
Role
Stealth / multirole combat aircraft
National origin
China
Manufacturer
Chengdu Aerospace Corporation
First flight
11 January 2011
Introduction
March 2017
Status
In service
Primary user
People's Liberation Army Air Force
Produced
Number built
8 prototypes and
20+ initial production fighters
Unit cost
US$110 million as of 2011
Developed from
J-XX
In November 2015, a new J-20 prototype, numbered '2017', took to the sky. The
most significant change in the new prototype is the reshaped cockpit canopy,
which provides the pilot with greater visibility. The lack of other design
changes suggest that "2017" is very close to the final J-20 production
configuration. Since '2017' is likely the last J-20 prototype, low rate initial
production of the J-20 is likely to begin in 2016. It has been reported that the
design of J-20 is already mature and will not directly use the 117S engine.
As of March 2017 there were still a series of technical problems that needed to
be tackled, including the reliability of its WS-15 engines, [the aircraft's
flight] control system, stealth coatings and hull materials, and infrared
sensor.
At least six J-20s are in active service, with tail numbers 78271-78276
identified. Another six were believed ready to be delivered by end of Dec 2016.
On 9 March 2017, Chinese officials confirmed that the J-20 had entered service
in the Chinese air force.
In September 2017, the J-20 officially entered military service with PLAAF,
making China the second country in the world after United States wielding
fifth-generation stealth aircraft, and the first in Asia.
In January 2018, Chinese media reported that the J-20 is in full operation-ready
deployment.
Specifications
General characteristics
Crew: one (pilot)
Length: 20.4 m (66.8 ft)
Wingspan: 13.5 m (44.2 ft)
Height: 4.45 m (14 ft 7 in)
Wing area: 78 m2 (840 sq ft)
Empty weight: 19,391 kg (42,750 lb)
Gross weight: 32,092 kg (70,750 lb)
Max takeoff weight: 36,288 kg (80,001 lb) upper estimate
Fuel capacity: 11,340 kg (25,000 lb) internally, or 19,340 kg (42,600 lb) with
(19,500 lbf) thrust each dry, 140 kN (32,000 lbf) with afterburner
Maximum speed: 2,100 km/h (1,305 mph; 1,134 kn)
Wing loading: 410 kg/m2 (84 lb/sq ft)
Thrust/weight: 1.06 (prototype with interim engines)
Armament
PL-8 short range AAM
PL-10 SRAAM
PL-12 Medium Range AAM
PL-21 Long Range AAM
LS-6 Precision-guided bomb
Avionics
Type 1475 (KLJ-5) active electronically scanned array
EOTS-86 electro-optical targeting system
EORD-31 infrared search and track
Distributed aperture system
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