The Indian Air Force needs new fighters. It needed them pretty badly before the current conflict with China over a stretch of the Himalayas that both countries claim. Now it needs them even worse. On Monday, Chinese forces killed 20 Indian soldiers in a skirmish along the disputed India-China border running through the towering mountain range. Forty-three Chinese soldiers also were injured or died, according to press reports.

So it should come as no surprise that India this week reportedly placed a $780 million order with Russia for 33 fighters, enough to equip or equip two squadrons. What’s weird is which fighter types New Delhi reportedly is buying. The Indian order includes 21 MiG-29s and 12 Su-30s, according to press reports. But one aviation expert believes the Sukhois in particular are a poor fit for mountain patrols.

The Indian Air Force reportedly long had planned to buy the extra planes to bolster the service’s existing arsenal of around 230 Su-30s and 60 MiG-29s. The air arm also plans, in coming years, to buy 83 locally-made TEJAS light fighters as well as 144 foreign-made medium fighters.

All the new fighters—the Sukhois, MiGs, TEJAS and medium fighters—are part of an effort to grow the air force from 28 front-line squadrons to 40, the number New Delhi considers adequate to fight both Pakistan and China at the same time.

Those 28 squadrons fly a bewildering variety of fighters, including Indian- and Russian-made types, French Mirage-2000s and Rafales and European Jaguars.

The Rafale, Su-30 and MiG-29 are candidates for the medium-fighter requirements. American firms Lockheed Martin LMT and Boeing BA also are vying for the multi-billion-dollar contract with, respectively, a highly upgraded F-16 and the F/A-18E/F. Swedish company SAAB is offering its Gripen fighter.

Tom Cooper, an author and aviation expert, expressed his surprise that the Indian air force reportedly wants Su-30s and MiG-29s to meet its emergency requirement for a couple squadrons worth of jets. The Su-30, while seemingly impressive on paper, lacks performance and combat capability compared to Western models.

“Your air force has got 200 to 250 Su-30s,” Cooper pointed out on Facebook. “Still, when you want to bomb a terrorist gang in the neighbouring country, you need almost 40-year-old Mirage 2000s, instead.”

Cooper was referring to the February 2019 clash between Indian and Pakistani forces over disputed Kashmir, roughly in the same region where Indian and Chinese troops would collide more than a year later.

Indian Air Force Mirage 2000s initiated the combat with a precision strike on a suspected terrorist base inside Pakistani territory. Pakistan responded with F-16s. When the dust settled, the Indians had lost a single MiG-21 fighter.

Those same Mirage 2000s had been decisive during an earlier conflict in Kashmir back in 1999. India’s Russian-made fighters had struggled to strike Pakistani bases high in the mountains. But a single coordinated strike by Mirage-2000s hauling Litening camera pods and laser-guided bombs succeeded in knocking out a key Pakistani headquarters.

“In these attacks, the target was acquired through the Litening pod’s electro-optical imaging sensor at about nine miles out, with weapons release occurring at a slant range of about five miles and the aircraft then turning away while continuing to mark the target with a laser spot,” Air Force Magazine noted in 2012.

Cooper’s point is that, for decades, the Mirage-2000 has been a more effective fighter in Indian service than the Su-30 has been. The Rafale, the French-made successor to the Mirage, likewise is among India’s better fighters. But the country has ordered just 36 Rafales.

The Su-30 not only lacks the latest precision air-to-ground ordnance, it doesn’t perform well from the high-altitude air bases that support Indian operations along the so-called “Line of Actual Control,” the border between Indian and Chinese forces in the Himalayas. Diplomats drew that line as part of truce talks following a bitter, bloody border war in 1962.

Kushok Bakula Rimpochee Airport in the Indian city of Leh supports Indian warplanes for operations over the Himalayas. The Indian army’s ongoing efforts to improve a road between Leh and an Indian outpost just a few miles from Line of Actual Control might be what incited the current clash.

Kushok Bakula Rimpochee’s 9,000-foot runway is situated 11,000 feet above sea level. The Su-30 doesn’t work well in those conditions, according to Cooper. “They’re happy if the jet can launch while carrying two [air-to-air missiles],” Cooper wrote. “And brake-discs and tires must be replaced after every single sortie.”

The lighter MiG-29 apparently functions better in Leh than the Su-30 does. But that doesn’t mean the old MiG is the right choice for India. The MiG-29s New Delhi plans to buy from Russia apparently are outdated models that Russian workers will refurbish before handing over. “They are simply not up to the task,” Cooper said of the MiG-29s.

So why, when confronted with an encroaching Chinese army, does the Indian air force want Sukhois?

It should be obvious. Indian firm HAL builds the Su-30s under license in India. Buying Sukhois funnels Indian money to Indian companies. Although, as Cooper pointed out, with adequate political will India could license the Rafale, too.

“The experiences of last year should’ve brought the Indians to their senses,” Cooper said. “They could’ve bought more Rafales.”