你估计中国成都歼-20的雷达反射截面积（RCS）是多少？与F-35相比，它比F-35小多少或大多少？

Sy Gunson X-band figures are the most pertinent, therefore in X-band, F35 RCS is 0.09m2 Versus 0.21m2, J20 RCS, Offsetting this, the F35 has obsolete Gallium Arsenide APG 81 radar. China and Russia have both abandoned Gallium Arsenide for Gallium Nitrate AESA radar.

X 波段的数据最为相关，因此在 X 波段，F-35 的 RCS 为 0.09 平方米，而 J-20 的 RCS 为 0.21 平方米。 补偿这一点的是，F-35 配备的是已过时的砷化镓（Gallium Arsenide）APG-81 雷达。中国与俄罗斯都已放弃砷化镓，转而采用氮化镓（文中称“Gallium Nitrate”）的有源相控阵雷达。

The J20’s Gallium Nitrate radar emits 50% more power and has a third greater detection range. Without Technical Refresh-3, the F35 can’t be equipped with better radar. The standard F35 only provides 14 kW Electrical power for cooling and avionics. An upgrade for the APG-85 radar so it can use the AIM120D missile, demands generating 62kW This in turn requires engine modifications to the PW135 engine which Lockheed Martin first requested in 2008.

歼-20战机的氮化镓雷达功率提升50%，探测距离增加三分之一。若未进行技术升级-3项目，F35无法配备更先进的雷达。标准版F35仅能为冷却系统和航电设备提供14千瓦电力。为升级APG-85雷达使其能搭载AIM-120D导弹，需将供电能力提升至62千瓦，这又要求对普惠PW135发动机进行改造——洛克希德·马丁公司早在2008年就已首次提出此项改进需求。

The F35 is dangerously obsolete with existing radar/avionics and is incapable of upgrading without planned upgrades which are stalled, or lack funding. Until it has these upgrades it is stuck with the short range AIM 120C missile.

在现有雷达/航空电子情况下，F-35 存在严重的过时风险，且若计划中的升级被搁置或缺乏资金就无法完成升级。在完成这些升级之前，它只能受制于射程较短的 AIM-120C 导弹。

F35’s RCS

F-35 的 RCS：

F35** in X-band (8.15 GHz) is 0.09m2 F35 in S-band (3.15 GHz) is 0.09m2 F35 in L-Band (1.15 GHz) is 0.27m2 F35 in VHF (0.15 GHz) is 1.66m2 F-35 (clean)**

F-35 在 X 波段（8.15 GHz）为 0.09 m² F-35 在 S 波段（3.15 GHz）为 0.09 m² F-35 在 L 波段（1.15 GHz）为 0.27 m² F-35 在 VHF（0.15 GHz）为 1.66 m² （F-35 空机状态）

J20 RCS

J-20 的 RCS：

J20 in X-band (8.15 GHz) is 0.21m2 J20 in S-band (3.15 GHz) is 0.21m2 J20 in L-Band (1.15 GHz) is 0.24m2 J20 in VHF (0.15 GHz) is 1.15m2

J-20 在 X 波段（8.15 GHz）为 0.21 m² J-20 在 S 波段（3.15 GHz）为 0.21 m² J-20 在 L 波段（1.15 GHz）为 0.24 m² J-20 在 VHF（0.15 GHz）为 1.15 m²

Orophen I find it funny that all of these other jets are so much better, yet where the U.S. excels is in manufacuring them. So you expect this wonder machine to take out all support and supply lines behind the over 1,000 F35s as well as the all the support the F35 gets from all the other craft in the US Military? Good luck.

我觉得好笑的是，大家都说别的战机好得多，但美国擅长的恰恰是制造这些飞机。所以你真指望这台“神机”能切断支撑 1000 多架 F-35 的所有补给与后勤，连同美军其他飞机对 F-35 的支援也一并干掉？祝你好运。

Will Pu F-35 outmatched in so many aspect, yet many numbed-brains will continue to snarl protectively.

F-35 在很多方面被压制，但许多麻木的人仍会本能地为它护航并咆哮。

Nejc Bernot Is a stealth fighter supposed to even use its onboard radar? Does that not kind of work against trying to stay hidden? From what I understand, the F-35 is meant to rely on an AWACS plane lighting up any opposition, so it can engage them without ever revealing its there.

隐身战斗机是不是本来就不该频繁使用机载雷达？那不是有悖于保持隐蔽吗？ 据我了解，F-35 设想主要依赖预警机（AWACS）来照亮敌方，这样它就可在不暴露自身位置的情况下进行攻击锁定。

Sy Gunson No fighter can assert air superiority without shooting down its rival. Pretty much using radar is necessary for hunting prey.

没有哪架战斗机能在不击落对手的情况下宣称取得制空权。基本上，使用雷达对于“猎杀”目标是必要的。

Nejc Bernot Not if you have another plane providing the radar. From what I’ve read, the F-35 is supposed to use the radar returns from friendly AWACS planes to obtain missile lock. Using your own radar is like screaming “Look at me, here I am” while stalking prey. It is much better if the first clue the enemy has that you are around is when their planes start falling from the sky.

如果另有飞机提供雷达，那就不必自己开雷达。据我所读，F-35 设想是利用友军预警机的雷达回波来获得导弹锁定。 自己开雷达就像在偷袭时大喊“看我在这里”，而更理想的情况是，敌人直到飞机开始掉下来才意识到你在场。

Lo Sam This analysis is not trustworthy. To start, J-20 canards are made of composite materials. They do not reflect radar waves. In fact, the J10 canards were made of composite materials as well. They are thin, flexible, and has no volume.

这种分析不可靠。首先，J-20 的鸭翼（canards）是复合材料做的，不会反射雷达波。事实上，J-10 的鸭翼也是复合材料，既薄又有弹性，几乎没有体积。

Darian Brook All materials reflect radio waves to some extent so yes the composite canards would produce a return albeit less so than metal.

所有材料在某种程度上都会反射电磁波，所以复合材料鸭翼确实会产生回波，只是比金属少得多。

Felix Su It is most likely an artifact of the model or the software or both. And you’re never going to be pointing a radar at another plane from the dead center front anyways. That would be 1 in a billion chance or higher.

这很可能是模型或软件（或两者）的伪像。 而且你也不可能从正前方正中心去对着另一架飞机指雷达——那种机位几乎是十亿分之一的概率甚至更低。

Oliver Schwarz “Australians analyzed it on a scale model coated with a publicly available RAM formula.” Publicly available? Now, that cannot be the formula the Chinese actually use??!! And why do Australians do that? Do they plan to attack China to block its PEACEFUL RISE? I also want MY NATION to RISE PEACEFULLY. Rise? Rise AGAINST OTHER NATIONS? RISE “OVER" JAPAN, THEN THE US? WILL YOU/THEY SEE THEMSELVES AS THE NEMESIS OF THE WHITE MAN?

“澳大利亚人用涂了公开可得雷达吸波材料（RAM）公式的实体模型进行了分析。”公开可得？那难道就不是中国实际使用的配方吗？！而澳大利亚为什么要这么做？他们打算攻击中国以遏制其“和平崛起”吗？我也希望我的国家能和平崛起。崛起？是要对抗别的国家崛起吗？要“超越”日本、然后超越美国吗？难道你/他们会把自己看成“白人宿敌”吗？

William Phillips China are making all sorts of noises in the South Pacific area, and Australia is very concerned about them. In case you haven’t noticed, whenever Australia brings up something that China don’t particularly like, China bans a export item from Australia. There’s a trade war on it way, if it hasn’t already started.

中国在南太平洋地区动作频繁，澳大利亚对此非常担忧。若你没注意到，每当澳大利亚提出令中国不满的事，中国就会禁止某项澳大利亚出口商品。可以说贸易战已在路上，若尚未全面爆发也已开始了。

Dominik Schachtsiek First of all: there is no comparison of the J-20 to the F-35. The J-20 has been a “remodeled” model of a twin engine prototype of the J-9 (60’s / 70’s) - the F-35 has been designed from scratch with stealth in mind. The opinions as well as the statements are going apart, about both RCS’s. The F-35 supposed to have an overall RCS of about 0.001m2 (lower in some areas) - this would be 10x bigger than the F-22 - however some (reliable) sources said, that the F-35 has a lower RCS than the Raptor. The J-20 is said to have a RCS of 1m2 - and some sources say that it is 0.5m2. It is likely though not smaller. There is one issue with the whole topic: some people (e.g. Bora Tas) suggest, that the shape of the jet is suggesting its stealth. But aerial stealth is a group of technologies - active & passive - not a single feature. That means, it only starts with the shape, it goes on to the substructure, to the radar absorbing paint, to the AESA radar with stealth features and electronic warfare suite. The Americans have more than 50 years of active stealth R&D. Most countries just considered it as significant, after the F-117A has been officially revealed and when it became apparent, how successful the sorties of the F-117A have been. That means that the USA has at least a head start of 30 years! Inclusive Echo-1 (program to simulate and determine the RCS of aircraft designs) which might be no more called Echo-1 (as it has been for sure refined and upxed).

首先：J-20 与 F-35 根本不可直接对比。 有人认为 J-20 是在 J-9（60–70 年代的双发原型机）基础上“改造”而来——而 F-35 则是从零开始为隐身设计的。 关于两机的 RCS 存在大量不同意见和说法。 有人认为 F-35 的总体 RCS 约为 0.001 m²（某些区域更低）——这将比 F-22 大 10 倍——但也有（可信）来源称 F-35 的 RCS 低于猛禽（Raptor）。 J-20 据称 RCS 为 1 m²，也有来源说是 0.5 m²，但总体看来不太可能更小。 整个话题有一个关键问题：有人（如 Bora Tas）仅凭飞机外形就推断隐身性。但航空隐身是一系列技术的综合（主动与被动），不是单一特征。这意味着隐身从外形开始，延伸至结构、雷达吸波涂层、具备隐身特性的有源相控画雷达和电子战套件等。 美国在隐身技术上的主动研发已有 50 多年。大多数国家是在 F-117A 官宣并且其出动取得成功后才把隐身视为重要技术的。这意味着美国至少领先约 30 年！包括 Echo-1（用于模拟和判断飞机设计 RCS 的项目），虽然现在可能已不再叫 Echo-1（肯定已被改进和更新）。

Alec Coulibaly Saying the J-20 is based on the J-9 is like saying the Dreamliner is based on the 767. There’s far more to aircraft design than just looks. If you’re going to make such claims you should provide a credible source.

说 J-20 基于 J-9 就像说 787基于 767 一样。飞机设计远比外观复杂得多。如果你要做这种断言，应该给出可靠来源。

Alvin Yap LMao… J-10 has an RCS of 0.5m2 to 1.5m2. You think J-20 has an RCS equivalent of J-10? And you think plaAF will accept J-20 if it has the same RCS as J-10? You really thought that the Chinese failed physics?

笑死……J-10 的 RCS 在 0.5–1.5 m²。 你以为 J-20 会和 J-10 的 RCS 相当？你以为中国空军会接受一款 RCS 与 J-10 相同的 J-20？ 你真的以为中国人的物理学比你还差吗？

MD Adnan Zisan J-9 was suppose to be a single engine fighter where J-20 is a dual engine fighter. And when you will have to replace a single engine with double you will have to go through changing the capacity of fuselage , fuel distribution system which will increase weight and lead in remodeling of stabilizers, wings and canards ultimately will change the whole structure. Only a persons with no knowledge about aeronautics will accuse this. Perhaps, you are accusing this on the basic of a fake Chinese guy named Juzuo Zhang’s review , Who says half failed Indian LCA project which roughly have just secured 5000 flight hours after 20 years of it’s first flight better than J-20.

歼-9原定为单发战斗机，而歼-20是双发战斗机。若要将单发改为双发，就必须调整机身容量、燃油分配系统，这会增加重量并导致需要重新设计水平尾翼、主翼及鸭翼——最终将改变整体结构。只有对航空知识一无所知的人才会提出这种指控。或许您是基于一个名为“Juzuo Zhang”的虚假中国人士的评论作出指责，此人竟宣称历时二十年仅积累5000飞行时数的半失败印度LCA项目比歼-20更优秀。

Secondly, The stealth shaping of the airfrx is the main player in reducing the radar cross section not RAM coatings. Radiation absorbing coatings do have a role here. They can roughly reduce radar cross section by 70–80% but not multiple times . For example you can search about F-16CM which had been coated with “HAVE GLASS V” recently roughly made it’s RCS to 1.2m2 from 5m2. Where F-16 is smaller in size than F-35.

其次，机体隐身外形设计才是降低雷达反射截面的主要因素，而非雷达吸波涂层。虽然辐射吸收涂层确实有其作用，能将雷达反射截面降低约70%-80%，但无法实现数量级式的缩减。例如可查阅配备"HAVE GLASS V"涂层的F-16CM战机案例：该涂层仅使其雷达反射截面从5平方米降至1.2平方米。须知F-16的机体尺寸本就小于F-35。

For some of you guys it’s not hard to believe that China has stolen the data of F-22 and F-35 but it’s hard for you guys to believe that J-20 is a stealth fighter.

对你们中有些人来说，很容易相信中国偷了 F-22 和 F-35 的数据，但却难以相信 J-20 真的是一款隐身战机。

Super China I. Basic Concepts of RCS Radar Cross Section (RCS) is the core indicator for uating the stealth performance of aircraft. A smaller numerical value indicates greater difficulty in radar detection. The RCS of modern stealth aircraft is typically 2-3 orders of magnitude lower than that of traditional aircraft (for example, the RCS of the F-16 is approximately 5 square meters). II. RCS Performance of J-20 ‌Optimal Stealth Angle‌ Within the range of ±15 degrees in the forward direction, the RCS of the J-20 is approximately 0.001 square meters (equivalent to the size of a golf ball). This data is derived from multiple combat simulation tests and expert analysis. ‌Wide Angle Range‌ When the detection angle expands to ±45 degrees, the average RCS may rise to <0.3 square meters, which is related to the reflection characteristics of the fuselage sides and the canard wings. ‌International Assessment‌ Foreign research institutions have calculated through models that the forward RCS of the J-20 is between 0.001 - 0.005 square meters, and the DSI intake duct and stealth coating technology have made significant contributions. II. RCS Characteristics of F-35 Official Data The frontal RCS design value of the F-35 is 0.0015㎡ (superior to that of the F-22A). It adopts a omni-directional stealth design, but when external weapons are carried on the underside of the aircraft, the RCS will increase to over 0.5㎡. Measured Differences Different frequency band tests show that the RCS of the F-35 fluctuates: S frequency band: 0.08 - 0.61㎡ L frequency band: 0.13 - 1.08㎡ Reference Comparison Some reports compare its RCS to 0.065㎡ (close to the size of a seagull), which may be related to the comprehensive stealth performance under actual combat conditions. Comparison between J20 and F35: Angle Sensitivity The J-20 has a more prominent stealth advantage in narrow angles (the range commonly used in air combat), while the all-directional stealth design of the F-35 is more adaptable in complex battlefield environments. ‌Technical Focus‌ The J-20 reduces its RCS through super-material skins and aerodynamic layout optimization, while the F-35 relies on sensor fusion and dynamic stealth management. ‌Practical Impact‌ Simulations show that the J-20 can detect the F-35 at a distance of over 100 kilometers, while the F-35's detection range of the J-20 may be shortened to within 30 kilometers, creating a "one-way transparency" advantage. Super China

一、RCS 基本概念 雷达散射截面积（RCS）是评估飞机隐身性能的核心指标，数值越小表示被雷达探测的难度越大。现代隐身飞机的 RCS 通常比传统飞机低 2–3 个数量级（例如 F-16 的 RCS 约为 5 平方米）。 二、J-20 的 RCS 表现 最佳隐身角度： 在正前方 ±15 度范围内，J-20 的 RCS 大约为 0.001 平方米（相当于一个高尔夫球的大小）。该数据来自多次战斗仿真测试与专家分析。 宽角范围： 当探测角度扩展到 ±45 度时，平均 RCS 可能上升到小于 0.3 平方米，这与机身侧面和鸭翼的反射特性有关。 国际评估： 国外研究机构通过建模计算出 J-20 的正向 RCS 在 0.001–0.005 平方米之间，且 DSI 进气道与隐身涂层技术对其贡献显著。 三、F-35 的 RCS 特性 官方数据： F-35 的正面 RCS 设计值为 0.0015 m²（优于 F-22A）。它采用全向隐身设计，但当机腹外挂外部武器时，RCS 会增加到超过 0.5 m²。 实测差异： 不同频段测试显示 F-35 的 RCS 存在波动： S 波段：0.08–0.61 m² L 波段：0.13–1.08 m² 参考比对： 有些报告将其 RCS 比作 0.065 m²（接近海鸥大小），这可能与实际作战条件下的综合隐身性能有关。 J-20 与 F-35 的比较：角度敏感性 J-20 在狭窄角度（即空战常用角度）上具有更明显的隐身优势，而 F-35 的全向隐身设计在复杂战场环境中更具适应性。 技术侧重： J-20 通过超材料外皮和气动布局优化来降低 RCS，而 F-35 则依赖传感器融合与动态隐身管理。 实际影响： 仿真显示 J-20 可以在 100 公里以上探测到 F-35，而 F-35 探测 J-20 的距离可能缩短到 30 公里以内，形成一种“单向透明”的优势。