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The Chinese J-20 fighter performed a rare flight demonstration recently, showing off its manoeuvrability for the first time after the 2021 China Airshow. As promised, I am sharing this video with you to analyse the latest flight demonstration.

中国歼-20战斗机在2021年中国航展后首次进行了罕见的飞行表演，展示了其机动性。正如我所承诺的，我将与大家分享这段视频，以分析这次最新的飞行演示。

Last year, the J-20 made a strong impression with a flight display at the China Airshow. The Chinese military actually claimed the flight was somewhat restricted, not revealing the full capacity of the J-20, but it was still exceptionally impressive, including a few post-stall manoeuvres, such as Tail Slide. This time, the J-20 demonstration is low-key, but it is still a very interesting flight demonstration worth investigating further. The latest demo of the J-20 was carried about at the Air Force Achievement airshow in northern China. It started with the landing gear down, low altitude, low speed flypast, including low speed turning at an angle. That is mainly to show the low speed stability and manoeuvrability of the aircraft, which is the basis of having great anti-stall performance.

去年，歼-20在中国航展上的飞行表演给人留下了深刻的印象。中国军方实际上声称此次飞行存在一定的克制，没有展现歼-20的全部能力，但它仍然非常的令人印象深刻，包括一些失速后的动作，如尾滑。这次歼-20的演示比较低调，但仍然是一次非常有趣的飞行演示，值得进一步研究。歼-20的最新演示是在中国北方的空军成就航展上进行的。从放下起落架开始，低空，低速飞行，包括低速转弯。主要是展示飞机的低速稳定性和机动性，这是飞机具有良好的防失速性能的基础。

The J-20 also did low speed turns, likely at an angle of 40 or 50 degrees. Some analysts believe that the speed is similar to the landing speed of the S-U-27 fighter. The speed and altitude have been maintained, proving the J-20 can be very stable even at such a low speed. While doing so, a few J-20 control surfaces were not deflecting. That is an indication of good stability design at low speed. When all surfaces are in action, the pilot would be able to complete much greater manoeuvres, for example, swiftly pointing the nose at the enemy direction, then locking on and firing a missile. Adding to that, the J-20’s two V tails deflect inward together, generating a positive lift. The static stability of the J-20 at this moment is negative. The two canards are level; they are not even needed in this maneuver. The main wing slats are also level. In summary, the J-20 definitely has an impressive statically unstable design. Therefore, when all the surfaces are in action, the J-20 can perform exceptionally high-maneuver moves.

这架歼-20也做了低速转弯，可能是40或50度角。有分析认为，这一速度与SU-27战斗机的着陆速度相似。该速度和高度得到保持，证明歼-20即使在如此低的速度下，也可以非常稳定。在此过程中，一些歼-20的控制面没有偏转。这是低速稳定性设计良好的标志。当所有的表面都在工作时，飞行员将能够完成更大的机动，例如，迅速地将机头指向敌人的方向，然后锁定并发射导弹。此外，歼-20的两个V型尾翼一起向内偏转，产生正升力。这时歼-20的静稳定性是负的。两个鸭翼是水平的；在这种机动中，甚至不需要用到它们。主翼板也是水平的。总之，歼-20绝对有一个令人印象深刻的静态不稳定设计。因此，当所有的表面都在工作时，歼-20可以执行非常高的机动动作。

The next thing the J-20 did was a small angle climb plus a half loop, an integration of multiple manoeuvers. The half loop is similar to some post stall manoeuvres and only takes 3 seconds to complete. That demonstrates how quickly the J-20 can change course. Next, the J-20 performed minimal radius turns. At last year's airshow, the J-20 did that, too. This part proves this much larger, heavier, stealthy fighter can make a turn as quickly as an F-16 fighter with an air combat payload. And the F-16 is well known for its world-class maneuverability. This is downright impressive.

接下来，歼-20做了一个小角度爬升加上一个半环，综合了多种机动。半环类似于一些后失速动作，只需要3秒就完成了。这证明了歼-20改变航向的速度很快。接下来，歼-20进行了最小半径转弯。在去年的航展上，歼20也做到了这一点。这部分证明了这种更大、更重、隐形的战斗机可以像F-16战斗机一样快速地进行空战。F-16以其世界级的机动性而闻名。这一点真是令人印象深刻。

This time, the J-20’s turning angle is around 80 degrees. The turn is steady, and the G force is roughly 6G. If we look at the angle of attack, control surface deflection, and engine thrust level indicated by nozzle status change, we can confirm that the J-20 is flying at an intermediate status and it matches the extreme performance of an F-16C fighter.

这一次，歼-20的转弯角度在80度左右。这个转弯很稳定，重力大概是6G。如果我们观察喷嘴状态变化所显示的攻角、操纵面偏转和发动机推力水平，我们可以确认歼-20是在中间状态飞行，它与F-16C战斗机的极限性能相匹配。

Keep in mind that the J-20 has not yet received its designated turbofan engine or vector thrust nozzle. When these two improvements are delivered to the future J-20 variant, the fighter can achieve even higher maneuverability.

记住，歼-20还没有收到为它指定的涡扇发动机或矢量推力喷嘴。当这两种改进交付给未来的J-20改型时，这种战斗机可以实现更高的机动性。

The last part of the flight demo is a steep climb plus a high angle of attack roll. Some analysts point out that, observing the wingtip vortex, the J-20 is actually at a higher angle of attack when doing the climb and roll. Therefore, this is not just a basic climb and roll routine. If we look at these continuous screenshots of the flight, we can easily see that within less than 3 seconds, the J-20 has completed a 360-degree roll with a high angle of attack, and the nose direction of the J-20 has changed over 40 degrees per second. That is actually another proof of the J-20’s world-class post-stall manoeuvre capability. And this is why the J-20 pilot chose to perform this part; it tells everyone how great this fighter is.

飞行演示的最后一部分是一个陡峭的爬升加上一个大的迎角滚转。一些分析人士指出，观察到翼尖涡，歼-20在爬升和滚转时，实际上攻角更高。因此，这不仅仅是一个基本的攀爬和翻滚动作。如果看这些连续的飞行截图，我们很容易看到，在不到3秒的时间里，歼-20完成了大迎角的360度滚转，机头方向每秒变化超过40度。这实际上是歼-20世界级失速后机动能力的另一个证明。这就是为什么J-20飞行员选择执行这个部分；它告诉所有人这架战斗机有多棒。

Lastly, again, this routine is completed without a great turbofan engine similar to what the US F-22 has, and there is no vector thrust control involved. For many people, they can’t wait to see what the ultimate variant of the J-20 can do in a flight demonstration.

最后，同样，这套动作是在没有采用类似美国F-22的大型涡扇发动机的情况下完成的，而且没有涉及矢量推力控制。对于许多人来说，他们迫不及待地想要看到歼-20的终极改型在飞行演示中能做什么。