The J-31 fighter jet, also known as the Shenyang FC-31 or J-21, is a Chinese twin-engine, mid-sized fifth-generation jet fighter currently under development by Shenyang Aircraft Corporation. Since its first flight in 2012, there have been discussions about its similarity in appearance and intended role to the American F-35 Lightning II.
Background on the J-31 and F-35
The J-31 is envisioned as a rival to American jets like the F-35 Lightning II, which is a single-seat, single-engine, all-weather stealth multirole fighter undergoing final development and testing by the United States. Lockheed Martin is developing three variants for the United States and eight international partners: the F-35A conventional takeoff and landing (CTOL) variant, the F-35B short take-off and vertical-landing (STOVL) variant, and the F-35C carrier-based catapult-assisted take-off but arrested recovery (CATOBAR) variant.
The F-35 first flew in 2006 and entered service with the US Marines in 2015. The Chinese government began developing the J-31 in the late 2000s, with the goal of producing an affordable, exportable fifth-generation fighter to compete with the F-35 on international markets.
Visual similarities
There are some clear visual similarities between the J-31 and F-35 designs. Both aircraft utilize a conventional swept-wing, twin-engine layout with rounded fuselages and vertical stabilizers canted at an angle. They both feature dorsal engine intakes and internal weapon bays capable of holding medium and short-range missiles.
Specific similarities include:
- Trapezoidal wings with identical sweep angles (32 degrees for the leading edges, 42 degrees for the trailing edges)
- Chined forebody shape
- Twin dorsal engine intakes
- Inclined vertical stabilizers
- Internal weapons bay
However, there are also some noticeable differences between the two aircraft:
- The J-31 has two smaller horizontal stabilizers while the F-35 has larger almost stabilator-like horizontal fins
- The J-31 has more conventional round engine nozzles while the F-35 has rectangular nozzles
- The J-31’s nose and cockpit appear flatter while the F-35 has a more rounded “bird-like” profile
Intended roles
The J-31 and F-35 do share similarities in their intended mission sets as well. Both jets incorporate low-observable stealth technologies and are capable of penetrating sophisticated air defenses to strike ground targets. Key aspects include:
- Air-to-ground attack role – ability to carry precision-guided munitions internally
- Beyond visual range air-to-air combat role
- Networked sensor fusion and data sharing
- Some level of electronic warfare/survivability capabilities
However, there are some differences in mission profiles as well. The F-35 comes in three variants for conventional, vertical landing, and carrier-based operations. The J-31 is presumed to be for land-based operations only at this point. The F-35 also places greater emphasis on providing close air support to ground troops. The J-31s priorities appear to be long-range interception and striking defended targets deep in enemy territory.
Technical capabilities
While any detailed assessments of the J-31’s capabilities remain speculative since it is still under development, some observers note the following potential areas of comparison:
Specification | J-31 | F-35 |
---|---|---|
Max speed | Mach 1.8 | Mach 1.6 |
Combat radius | 1,200+ km | 1,100+ km |
Radar type | AESA | AESA |
Internal weapon bay | 4-6 missiles | 4-6 missiles |
This suggests that the J-31 potentially matches or exceeds the F-35 in some respects like speed and range. It definitely makes use of advanced technologies like active electronically scanned array (AESA) radars and extensive use of composite materials to reduce weight and radar cross-section.
However, the F-35 is further along in its development and testing cycle and integrates many advanced networked sensors and mission systems. The sensor fusion capabilities that allow F-35 pilots enhanced situational awareness and the ability to take full advantage of stealth features may be lacking on the J-31.
Development status
The F-35 has been under development since the 1990s, whereas the J-31 only had its first flight in 2012. The F-35 has completed most of its flight test program, with over 17,000 flight hours as of early 2019 across all three variants. Low-rate initial production began in 2006. As of 2022, nearly 800 F-35s have been built and delivered to operators in the United States and allied nations. It is already operational and being deployed in combat roles by multiple air forces.
In contrast, the J-31 remains in the prototype phase with only a handful of airframes for testing. There are reports that the development has been beset by technical issues with the engines and flight control systems. Low-rate initial production is not expected until after 2025, with potential mass production possibly a decade away. The design remains unproven and untested relative to the more mature F-35 platform.
International exports
A key driver behind the J-31 program is providing an affordable and capable fifth-generation fighter for export to international customers. The F-35 was intended primarily for use by the United States and core partners like the UK, Israel, Japan, etc. While the F-35 has seen some small export sales, tight government restrictions remain on who can purchase the aircraft.
Chinese aviation firms hope to leverage the J-31 and market it to nations unable to purchase the F-35 or other top-tier Western aircraft. Pakistan is considered one of the most likely potential export customers. The J-31 would provide capabilities rivaling India’s recent acquisition of French Rafale jets. Export sales would help offset some of the J-31’s development costs for Chinese manufacturers.
Strategic implications
Some analysts see the J-31 program as part of China’s broader military-technological competition with the United States. China has struggled to keep pace with American development of stealth aircraft over the past decades. The J-31 represents a long-term effort to produce a capable indigenous stealth fighter that can hold its own against the F-35 and F-22.
For the United States and its Pacific allies like Japan and South Korea, the emergence of the J-31 raises concerns about maintaining regional air superiority in the coming decades. Proliferation of the J-31 could begin to erode the qualitative edge American forces have long held in stealth and other technologies. It also touches on issues of defense technology theft – while China has made strides in indigenous design, some still allege the J-31 heavily leverages stolen F-35 secrets.
Conclusion
The J-31 fighter still remains under development and specifics about its capabilities are lacking. However, it does bear some strong resemblance to the American F-35 in terms of form, function and intended mission profile. The visual similarities are clear, but differences exist as well, especially in terms of maturity and avionics/sensor integration. The J-31 is positioned as China’s answer to the F-35, an affordable stealth fighter that can be exported abroad and challenge American dominance of fifth-generation platforms. Continued progress on the J-31 program will have implications for the balance of power in the Pacific region and beyond.