Obvious significant differences between Chengdu J-20 and Lockheed F-22
The Chengdu J-20 is nothing like the F-22. If you look carefully, it should be obvious.
1. The Chengdu J-20 is a canard-delta wing fighter. The J-20 has no rear horizontal stabilizers, which is present on the F-22 quad-tail design.
The F-22 has large trapezoidal wings to maximize maneuverability. In contrast, the J-20 is optimized for transonic flight. To compensate, the J-20 has ventral stabilizers and adjustable vertical stabilizers to increase maneuverability.
2. Your eyes should be able to see the DSI (ie. diverterless supersonic inlet) on the Chengdu J-20, which is absent on the F-22.
3. The transparent RAM on the F-22 is much thicker and the gold color is more noticeable. This means the J-20 and F-22 are most likely using different chemical compounds.
4. The EOTS (ie. electro-optical targeting system) on the J-20 is not present on the F-22.
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Differences between Chengdu J-20 and Lockheed F-22 design philosophies
The Chengdu J-20 is a "genuine Very Low Observable design" except for round engine nozzles, which can be fixed.
The Chengdu J-20 and Lockheed F-22 are optimized for different functions (see citation below).
The Chengdu J-20 is not a larger F-22 with canards. The J-20 has no rear horizontal stabilizers, which is present on the F-22 quad-tail design.
The combination of the canards, delta wing, and rhomboid vertical stabilizers indicate a design strategy to optimize for supersonic flight. Basically, the J-20's main purpose is to stealthily fly long distances in supercruise.
The F-22 has a diamond wing with a large surface area and large trapezoidal vertical stabilizers to provide stability. Additionally, the F-22 has thrust-vectored flat nozzles. It looks like the designers of the F-22 were optimizing for maneuverability in close combat.
The design philosophies behind the J-20 and F-22 are completely different (see reference below).
Also, you will note the J-20 has active vertical stabilizers and the F-22 has static vertical stabilizers. My guess is the J-20 has active vertical stabilizers to increase its maneuverability.
The Chengdu J-20 designers did something very clever. They built canard, delta-wing, and rhomboid vertical stabilizers to optimize for supercruise (which enlarges the combat radius during supersonic combat). However, they designed an active vertical stabilizer to work in concert with the canards and ventral stabilizers to increase maneuverability. Overall, an ingenious J-20 design that maximized supercruise range and combined it with very good maneuverability.
Reference:
Aspects of Wing Design for Transonic and Supersonic Combat
Citation:
The Strategic Impact of China's J-XX [J-20] Stealth Fighter
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Claims that the Chengdu design is a “Sino-F-22A” make little sense, if the latter were true the aircraft would be considerably smaller. Unlike the FB-22 proposals,
the J-XX [J-20] is clearly intended for air combat and using a canard-delta configuration will provide both efficient supersonic cruise, and good supersonic and transonic manoeuvre performance if fitted with engines of sufficient thrust rating[vii]."