Russia’s air force is hollowing itself out. More air defense can help.

The Russian Aerospace Forces, or VKS, continues to burn through the life span of its fighter aircraft in the war against Ukraine . After two years of air war, its total force is slightly less than 75% of its prewar strength.

The VKS has directly lost approximately 16 fighters over the past eight months. However, this does not account for the imputed losses, which arise from an aircraft accruing more flight hours than planned, reducing its overall life. Based on updated information, the VKS is on track to suffer approximately 60 imputed aircraft losses this year from overuse. That is equivalent to losing 26 new airframes. Meanwhile the VKS currently procures only about 20 total Su-30, Su-34 and Su-35 aircraft per year.

The air war has mostly maintained a steady state since mid-2023, with the exception of February 2024, when the VKS flew approximately 150 sorties per day in support of the Avdiivka offensive. Given that Russia also has been using longer-range glide bombs and devoted more aircraft to air-to-ground roles, the average sortie duration has also likely decreased, reducing the accelerated aging. Still, slightly more than half of the VKS’ tactical airframes are more than 30 years old; these have far fewer flight hours left.

The accelerated aging may be shaping Russia’s combat operations. The majority of VKS fighters operating (and lost) over Ukraine are the newer Su-30, Su-34 and Su-35 aircraft with occasional reported sightings of Su-25s.

The older MiG-31s and Su-27s have been relegated to supporting hypersonic Kinzhal strikes and air patrol at a distance. With an estimated average remaining airframe life of less than 20% and 35% respectively, these older aircraft can be used for this war, but likely have insufficient life to support Russia’s potential future invasions .

Russia’s air-to-air warfare MiG-29s are totally absent, even from air-patrol missions. Given their age, these aircraft may be either unserviceable or are being kept in reserve for a final mission. Regardless, whether due to lack of upgrades, survivability or age, these are effectively paper airplanes.

The Su-24s, on the other hand, were used extensively in the invasion of Ukraine. But there have been no reports of Su-24 losses thus far in 2024. How much are they still flying? These aircraft are old; the newest models were manufactured in 1993 . The VKS may have chosen not to configure them for their new FAB-1500 glide bombs, which would also hint at the fact that the Su-24s may be reaching the end of their useful lives.

Ukraine, which is short on air defense munitions, has a few options to accelerate Russian air losses. Attacking air bases would likely reduce VKS sortie rates by more than 20% by disrupting operations and forcing the VKS to fly from more distant bases. The greatest opportunity remains the effect of forthcoming F-16 jets (and possible Gripens ) to divert VKS sorties from ground-attack to air-to-air efforts.

Regardless, more air defense munitions and fighters will be critical to Ukrainian success. Russia is relying on only about 300 combined Su-30, Su-34 and Su-35 aircraft for its operations over Ukraine, including delivering the hugely destructive glide bombs . From a strategic perspective, shooting down these newest VKS aircraft imposes a larger cost to Russia and would have the greatest overall impact on the VKS’ ability to perform strikes. It would also improve the odds of survival of the 45 F-16s allies promised to Ukraine.

The VKS has fewer than 650 tactical aircraft when accounting for end-of-life aircraft; it has even less when accounting for accelerated usage. But these numbers are unlikely to change its behavior, based on Russia’s exhibited willingness to accept high losses even for trivial gains.

In comparison, NATO has roughly 800 fifth-generation aircraft, with another 100 or more arriving every year. This is more than sufficient to counter the VKS in the air and conduct targeted ground strikes, especially given the poor performance of Russian surface-to-air missiles in Ukraine.

To be sure, NATO should expand its production of air-to-air and surface-to-air munitions to deter further Russian aggression and support Ukraine. But with the VKS currently shrinking, the alliance can afford to donate more munitions to Ukraine now without worrying about its immediate strategic reserves.

Michael Bohnert is an engineer at the think tank Rand. He previously worked as an engineer for the U.S. Navy and the Naval Nuclear Laboratory.

俄罗斯空天军（VKS）在对乌克兰的战争中持续损耗其战斗机的寿命。经过两年的空战，其总兵力已不足战前水平的75%。

过去八个月，俄罗斯空天军直接损失了约16架战斗机。然而，这并未计入因飞机飞行时间超过计划而导致的间接损失，这些间接损失会缩短飞机的整体使用寿命。根据最新信息，俄罗斯空天军今年预计将因过度使用而遭受约60架间接损失，相当于损失26架新飞机。与此同时，俄罗斯空天军目前每年仅采购约20架苏-30、苏-34和苏-35战斗机。

自2023年中期以来，空战基本保持稳定，仅在2024年2月出现例外，当时俄罗斯空天军为支援阿夫迪伊夫卡攻势，每天出动约150架次飞机。鉴于俄罗斯也一直在使用远程滑翔炸弹，并投入更多飞机执行对地攻击任务，平均出动时长可能也有所缩短，从而减缓了飞机老化速度。尽管如此，俄罗斯空天军超过一半的战术飞机机龄已超过30年，剩余飞行时间已所剩无几。

加速老化可能正在影响俄罗斯的作战行动。在乌克兰上空作战（以及损失）的俄罗斯空天军战斗机大多是较新的苏-30、苏-34和苏-35型飞机，偶尔也有苏-25型飞机的目击报告。

老旧的米格-31和苏-27战机已被降级用于支援“匕首”高超音速打击和远距离空中巡逻。据估计，它们的剩余机体寿命分别不足20%和35%，这些老旧战机虽然可以用于此次战争，但可能不足以支持俄罗斯未来潜在的入侵行动。

俄罗斯的米格-29空战机完全缺席，甚至连空中巡逻任务也没有。考虑到它们的机龄，这些飞机可能已经无法使用，或者被作为预备役飞机留作最后一次任务。无论如何，无论是由于缺乏升级、生存能力不足还是机龄过老，这些飞机实际上都只是纸飞机而已。

另一方面，苏-24战机在入侵乌克兰的行动中被广泛使用。但截至2024年，尚未有苏-24战机损失的报告。它们目前还在服役吗？这些飞机已经老旧，最新型号也是在1993年生产的。苏联空军可能没有为它们配备新型FAB-1500滑翔炸弹，这也暗示着苏-24战机可能已经接近使用寿命的终点。

乌克兰防空弹药短缺，但仍有一些方法可以加速俄罗斯空中力量的损失。攻击空军基地可能会扰乱俄罗斯的作战行动，迫使其从更远的基地起飞，从而降低俄罗斯空天军的出动架次超过20%。最大的机会仍然是即将到来的F-16战斗机（以及可能的鹰狮战斗机）所带来的影响，即迫使俄罗斯空天军的出动架次从对地攻击转向空战。

无论如何，更多的防空弹药和战斗机对乌克兰的胜利至关重要。俄罗斯目前仅依靠约300架苏-30、苏-34和苏-35战机执行对乌克兰的作战任务，包括投掷威力巨大的滑翔炸弹。从战略角度来看，击落这些最新的空天军战机将给俄罗斯带来更大的损失，并对空天军的整体打击能力造成最大的影响。此外，击落这些战机还能提高俄罗斯承诺提供给乌克兰的45架F-16战机的生存几率。

如果将已退役的飞机计算在内，俄罗斯空天军的战术飞机数量不足650架；如果将加速使用的飞机也计算在内，数量则更少。但鉴于俄罗斯一贯愿意为微不足道的利益付出巨大代价，这些数字不太可能改变其行为。

相比之下，北约拥有约800架第五代战机，并且每年还会新增100架或更多。这足以在空中对抗俄罗斯空天军并进行定点对地打击，尤其是在俄罗斯地对空导弹在乌克兰表现不佳的情况下。

诚然，北约应该扩大空空导弹和地空导弹的生产，以遏制俄罗斯的进一步侵略并支持乌克兰。但鉴于乌克兰空天军规模目前正在缩减，北约现在可以向乌克兰捐赠更多弹药，而无需担心其眼前的战略储备。

迈克尔·博纳特是兰德公司（Rand）的一名工程师。他此前曾在美国海军和海军核实验室担任工程师。