新華網

中國人民解放軍空軍在2017年經歷了一個多事之秋。9月，中國空軍和巴基斯坦空軍在中國境內舉行了第六次“雄鷹（Shaheen VI）”聯合訓練。而台灣防務當局稱，截至10月份，中國空軍在2017年共進行了16次環島演習。值得注意的是，中國空軍在2017年擴大了軍事演習的幅度和範圍，吸引了該地區其他國家的注意。在某種程度上，2017年中國舉行的空軍演習與2016年相比有所降低，包括與日本航空自衛隊近距離接觸的頻度，但最後幾個月依然見證了一些轉變。

朝鮮和美國之間爆發的朝鮮核試驗僵局無疑是2017年東北亞地區最重要的安全議題。繼朝鮮進行了一系列史無前例的導彈試驗後，一些專家重新評估了平壤政權發展核武器的時間表，同時美國與韓國和日本沿韓國海岸線首次舉行了聯合軍演。目睹其東海防空識別區附近如此頻繁地舉行聯合軍演，加上“鷂鷹（Foal Eagle）”和“乙支自由衛士（Ulchi-Freedom Guardian）”等美韓年度聯合軍演，中國軍隊如坐針氈。

有鑒於此，中國空軍將軍事演習擴展至包括在朝鮮半島搜集情報的偵查任務。12月初中國宣布舉行的軍演就有偵察機的參與，這些偵察機或許已經飛越了中韓兩國防空識別區的重疊區域。作為對首爾和華盛頓的直接回應，這些軍事演習的威懾作用很有限。在當前情況下，美韓日聯合軍演與中國空軍演習間的對比只是更加凸顯了這種地區軍事力量不平衡的差距。中國空軍在太平洋地區面臨著兩個巨大的劣勢：作戰性能的技術局限和缺乏一個強有力的地區盟友。

在技術層面，中國空軍的確還有很長一段路要走。中國空軍在演習中使用的轟炸機基本上由“轟6K”組成，而“轟6K”是以早已過時的上世紀50年代蘇聯機體為基礎研製而成。美國則擁有三個由B-52H轟炸機組成的空軍聯隊，雖然該機型的服役期也較長，但都部署在美國本土，遠距離的太平洋作戰任務由更加先進的B-1B轟炸機執行。中國的“轟6K”已經升級改造為可搭載六枚對地攻擊巡航導彈，但該機型的有效負荷和制導設計限制了其從中國本土發動攻擊和威脅太平洋遠洋目標的能力。“轟6K”3500公里的預計航程令其在執行大部分轟炸任務時只能搭載艦載型CJ-20巡航導彈，這意味着“轟6K”可選擇的攻擊目標有限，且精確制導功能會受到影響。轟炸機的示警作用——以攻擊性的空中行動對新情況作出反應——會隨着重複使用而逐漸失去其威力。例如，出動B-1B轟炸機對每次朝鮮導彈試驗作出回應，會令美軍無法相應地增強應對朝鮮新威脅的能力。如果說美韓戰機飛越朝鮮半島起到的威懾作用有限，那麼中國空軍出動“轟6K”對海上軍演作出回應也僅僅顯示了中國的抗議無非就是不在乎多浪費一些航空燃油。

如果說有一個領域是中國空軍必須改進的，那就是發動機技術。中國當前服役的戰機幾乎全部使用俄羅斯發動機或從俄羅斯原型衍生而來的中國發動機，這些發動機都表現欠佳。對於“轟6K”以後的機型，它們的速度與範圍都令人失望。中國新生產的第五代戰鬥機“殲-20”在研發過程中配載了幾款發動機，現在使用的則是渦扇-15發動機。雖然渦扇-15的功能接近於美國上世紀90年代生產的發動機，但其機動性上沒有推力矢量，同時可靠性也欠佳。雖然中國空軍在短期內取得了長足的進步，但與美軍相比無疑仍存在巨大的差距。

而中國空軍的作戰孤立又加劇了其技術短板。連續六年的中巴“雄鷹”聯合軍演深化了中國空軍和巴基斯坦空軍的合作，但兩國間的同盟關係主要覆蓋內陸領土。讓我們對比一下中巴空軍合作與美韓日在該地區的軍事合作。進入21世紀20年代，美韓日將啟用洛克希德馬丁公司生產的F-35閃電II戰鬥機和韓國生產的KF-X戰鬥機，這兩種機型將令三國空軍脫胎換骨。而“殲-20”的一項優勢——遠程擊落行動緩慢的支援機——將被多用途的F-35戰機所抵銷。融合了指揮、控制、通訊、電腦、作戰系統、情報、監控和偵查等多功能的F-35戰機實際上就是一個取代那些易受攻擊支援目標的聯網平台。因此，美韓日三國F-35戰機的聯合作戰能夠發揮聚合效應，而這正是中國空軍所欠缺的。

鑒於中國空軍在東亞安全領域面臨著諸多不足，習近平將發展中國空軍列為一項優先議題。在10月份舉行的中國共產黨第十九次全國代表大會上，習近平在演講中點名提到了空軍和火箭軍，稱這兩者的發展對於建設“世界一流軍隊”至關重要。而新一代“轟-20”隱形轟炸機是朝實現這一目標邁出的重要一步。“轟-20”將成為中國版的美國B-2轟炸機，彌補“轟6K”能力上的不足。“轟-20”將令中國事實上完成自己的三位一體核打擊能力，而中國火箭軍在常規打擊能力上的進步本身就值得注目。美國戰略與國際研究中心（CSIS）在2016年發佈的一份報告中強調，短程和中程常規武器的發展和擴散對中國的威懾戰略來說至關重要。中國火箭軍於1966年作為第二炮兵部隊的分支機構設立，旨在發展中國的核武器威懾能力。火箭軍承擔的任務現已演變為雙重威懾——核武器和常規武器，而這一演變過程凸顯了中國在應對地區安全問題上更加多元化的思路。

習近平的強軍理念並非體現在硬件發展上，而是人員配備。新一屆中共中央軍事委員會副主席由原中國人民解放軍空軍司令員許其亮擔任，而原中國人民解放軍火箭軍司令員魏鳳和位列第三。雖然中國陸軍依然在中央軍委佔據着主導地位，但航空部隊已經開始崛起，而這一趨勢很可能會隨着航空實力的增強而得以強化。回顧2017年，當下的軍事演習暴露出中國空軍的局限性，凸顯了中國亟需一個地區盟友的必要性。但同時，中國空軍在過去一年中也取得了進步，而且這種趨勢將在未來幾年內得到延續。

(Xinhua)

The People's Liberation Army Air Force had an eventful year in 2017. September saw the sixth annual “Shaheen” exercises with Pakistani forces, and the Taiwanese defense ministry has reported sixteen PLAAF exercises in nearby airspace during the year ending in October. Notably, the PLAAF has expanded the range and scope of its exercises during 2017, drawing the attention of other regional actors. Chinese aerospace exercises are down from last year by some metrics, including the frequency of Japanese Air Self Defense Force scrambles, but the last few months have nevertheless been transformative.

Far and away the top Northeast Asia security story of 2017 was the standoff between North Korea and the United States. Following an unprecedented series of North Korean missile tests that led some experts to reevaluate the regime's development milestone timeline, American bombers conducted drills along the South Korean coast in coordination with Republic of Korea and Japanese fighters for the first time. Chinese forces are on edge with so many military operations taking place near the East China Sea air defense identification zone (ADIZ), in addition to annually conducted US-ROK exercises like Foal Eagle and Ulchi-Freedom Guardian.

Exercises conducted by the PLAAF have therefore expanded to encompass a reconnaissance role to collect intelligence on the Korean Peninsula. Reconnaissance aircraft took part in operations announced early in December, which may have overflown the area where the Chinese and South Korean ADIZs overlap. As a direct response to Seoul and Washington, these exercises offer limited utility in terms of deterrence. Under current circumstances, the contrast between US-ROK-Japan exercises and PLA operations has only served to highlight a regional mismatch. The PLAAF faces two glaring presence disadvantages over the Pacific: technological limitations to operational performance and a lack of a substantive regional alliance.

On the technology front, the PLAAF has quite a bit of catching up to do. Its bomber force, which has been deployed during exercises, is primarily made up of Xian H-6K aircraft based on an outdated Soviet airframe dating to the 1950s. The United States maintains three wings of B-52H bombers, similarly long in the tooth, but based on the American mainland; long-range Pacific duties fall to the more advanced B-1B. The H-6K has been thoroughly updated to carry six sophisticated land attack cruise missiles, but payload and guidance specifications hinder its ability to project power from the Chinese mainland and threaten targets deep into the Pacific. Its estimated combat range of 3500 kilometers limits the H-6K to the CJ-20 cruise missile in attacking most targets; that means fewer targets can be selected, and precision may suffer. The practice of bomber signaling – response to new developments with aggressive airborne exercises – loses its bite with repetition. For example, answering each North Korean missile test with a B-1B flight provides no escalated response to new North Korean threats. If US-ROK flights over the Korean Peninsula are of questionable utility, the PLAAF's reactionary maritime exercises with the H-6K demonstrate little more than a willingness to burn jet fuel in protest.

If there is a single domain in which the PLAAF needs to see improvement, it must be engine technology. Current operational aircraft almost invariably use Russian engines or Chinese derivative models with relatively poor performance. For models beyond the H-6K, that means disappointing speed and range. China's newly-minted fifth-generation fighter, the Chengdu J-20, has been mated to a variety of engines during its development and now uses the Xian WS-15. While the WS-15 comes close to matching the performance of American engines of the 1990s, it lacks thrust vectoring for maneuverability and has been dogged by reliability issues. Great strides have been made in a short time, but a gap undoubtedly remains.

Technological hurdles are compounded by China's operational isolation. The six years of Shaheen exercises have deepened cooperation between the PLAAF and the Pakistani Air Force, but the alliance covers primarily inland territory. Compare the PLAAF-PAF partnership to the array of American, ROK, and Japanese forces operating in the region. Entering the 2020s, those three nations' collective airborne presence will be transformed by the introduction of the Lockheed Martin F-35 Lightning II fighter and the ROK KF-X fighter. One of the J-20's likely strengths – knocking out slow support aircraft from long range – is stymied by the F-35's multirole capabilities. As a C5ISR (command, control, communications, computers, combat systems, intelligence, surveillance, reconnaissance) aircraft, the F-35 is a networked platform that replaces those vulnerable support targets. A joint operation involving US, ROK, and JASDF F-35s is therefore more capable than the sum of its parts, which cannot yet be said for any PLAAF configuration.

For all the issues facing the Chinese aerospace forces in the East Asian security landscape, Xi Jinping has made their progress a special priority. At the 19th Party Congress in October, Xi mentioned both the PLAAF and the PLA Rocket Forces by name during his address, marking them as crucial to the development of a “world-class force.” One step toward the realization of that goal is the upcoming Xian H-20 stealth bomber, which would become the Chinese equivalent of the American B-2 and address concerns about the H-6K's capabilities. While the H-20 will effectively complete the Chinese nuclear triad, the advancements made in conventional strike capabilities by the PLARF are notable in their own right. A 2016 CSIS report highlights the development and proliferation of short- and medium-range conventional weapons as crucial to China's deterrence strategy. The PLARF was founded in 1966 as a branch of the Second Artillery Corps, to develop the deterrence capabilities of the Chinese nuclear arsenal. Its evolution from that role, to one of dual deterrence – nuclear and conventional – evinces a more diversified approach to regional security.

Xi's vision is borne out not in the hardware, but in the personnel. The new, more exclusive Central Military Commission includes former PLAAF commander Xu Qiliang as vice chairman and former PLARF commander Wei Fenghe in the third rank. While the PLAA has maintained dominance in the Central Military Comission (CMC), the aerospace forces have risen in prominence and will likely continue to do so as their respective capabilities improve. The takeaway from 2017 is that while current exercises reveal PLAAF limitations and underscore China's need for a regional alliance, progress has been made and will continue over the coming years.