Summary and Key Points: Emerging details confirm that Ukraine's drone strike on Saturday likely damaged an advanced Russian aircraft, the Su-57 Felon fighter, potentially beyond repair.

-The attack targeted an airfield in Akhtubinsk, 350 miles from Ukraine, where drones evaded Russian defenses, damaged aircraft, and caused casualties among Russian personnel.

-Reports suggest that one or possibly two Sukhoi Su-57 jets, Russia's most advanced aircraft, were hit. Satellite images confirmed the base's attack, with credible claims of severe damage to at least one Su-57. The strike highlights Ukraine's increasing capability to target deep inside Russia, prompting potential changes in Russian military strategy.

-Additional details are emerging about Ukraine's strike that almost certainly damaged an advanced Russian aircraft – possibly beyond repair on Saturday.

Ukraine's Drone Strike Hits Russia's Advanced Su-57 Felon Jets

It has been confirmed attack was carried out with drones, which were used to strike aircraft on the ground at an airfield in Akhtubinsk approximately 350 miles (nearly 600 km) from Ukraine.

An undisclosed number of unmanned aerial systems (UAS) managed to evade Russian air defenses and struck the facility, damaging aircraft and killing and/or wounding a number of Russian military personnel.

Reports circulated over the weekend that a Russian Sukhoi Su-57 (NATO reporting name Felon) – the Russian Aerospace Force's most advanced aircraft – was among the planes to have come under attack, but a Ukrainian military intelligence official now suggests a second Su-57 may have also been hit. Each of the aircraft is reported to be worth $35 million to $54 million, according to the Foreign Policy Research Institute.

"There is preliminary information that there could have been two downed Su-57 aircraft," military intelligence spokesperson Andrii Yusov said in a television broadcast on Sunday, according to the Kyiv Independent.

"There is also information about irrecoverable losses and wounded among the occupiers' personnel," added Yusov.

Satellite images shared online over the weekend confirmed that the base had come under attack, and there are all indications that at least one Su-57 was seriously damaged in the raid. It is also quite likely that a second aircraft may have also taken at least some damage.

"It's a credible claim, even if photographic evidence has yet to emerge. The Russian air force concentrates many of its best in-development warplanes at the Akhtubinsk State Flight Test Center, including new Sukhoi Su-35 fighters, Okhotnik drones and­of course­Su-57s, which are Russia's answer to America's Lockheed Martin F-22 stealth fighters," wrote David Axe for Forbes.com on Sunday.

It is doubtful that the Kremlin expected that Akhtubinsk would be targeted, given its distance from Ukraine, even as Kyiv's forces have launched similar raids involving drones at distant airfields. Moreover, as Axe noted, both sides lack reinforced aircraft shelters and have a "bad habit" of parking high-value aircraft out in the open. Yet, Ukraine has done a better job of scattering its aircraft around the country, proactively trying to hide them from attack – whereas Russia continues to be reactive.

The Kremlin's response may be – as suggested by Russian propagandists on social media – to finally build some hardened shelters. Of course, that won't do much good for the one or possibly two Su-57s already taken off the board, but it could help protect the remaining fifth-generation fighters at the facility.

In addition, being forced to build shelters to protect its Su-57 and other aircraft could be an admission from Moscow that Kyiv's forces can – and will continue to – strike targets deep inside Russia.

"This is a really a trend that the Russians are worried about," said CNN contributor Jill Dougherty, the network's former Moscow bureau chief. "The Ukrainians are attacking more and more inside Russia and taking the battle to them."

Author Experience and Expertise: Peter Suciu

Peter Suciu is a Michigan-based writer. He has contributed to more than four dozen magazines, newspapers, and websites with over 3,200 published pieces over a twenty-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a Contributing Writer for Forbes and Clearance Jobs. You can follow him on Twitter: @PeterSuciu. You can email the author: [email protected].

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