A Russian Su-57 Felon fighter exploded on the tarmac in Russia’s western Astrakhan region on Thursday—marking at least the fourth of the aircraft damaged or destroyed this year.

Ukrainian officials are claiming that a Russian Aerospace Forces Su-57 Felon was seriously damaged—likely behind repair—after an engine mishap last week.

The aircraft was at the Akhtubinsk airfield in the Astrakhan region in western Russia along the Caspian Sea when it underwent a routine engine start-up. It is unclear what exactly went wrong, but the engine exploded, totaling the aircraft.

Initial rumors about the explosion circulated on Friday across social media, Ukraine’s Military Intelligence Directorate (HUR) announced on Monday that it had confirmation of the loss.

“The Su-57 is equipped with the AL-41F1 turbofan engine (also known as ‘Izdeliye 117’). One reason why engines of this type may explode or suffer catastrophic failure is the use of substandard fuel,” the HUR said—adding that Moscow has struggled to maintain stocks of high-quality aviation fuel due to Kyiv’s increased strikes on Russia’s domestic jet fuel production facilities, which it has mockingly described as “long-range sanctions.”

In the early hours of Sunday morning, Ukrainian drones also struck Russia’s fourth-largest refinery, a major producer of aviation fuel and gasoline. That facility had already suffered prior damage that suspended portions of its operations.

The Kremlin has increased its imports of aviation fuel, including Jet A-1 kerosene from Egypt, Belarus, and India. It has also imported aviation fuel from South Korea, leading to controversy in the West; Seoul has maintained that the fuel is not classified as a strategic military good under its domestic export control laws.

However, there are reports that some of the imported fuel was either of poor quality or was mishandled.

About the Su-57 Felon Fighter Jet

The “fifth-generation” stealth, multirole fighter was developed to combine the functions of an attack aircraft with those of a fighter jet and to engage and destroy various land, airborne, and maritime targets.

• Year Introduced: 2020
• Number Built: ~32
• Length: 65 ft 11 in (20.1 m)
• Wingspan: 46 ft 3 in (14.1 m)
• Weight (MTOW): ~77,160 lb (35,000 kg)
• Engines: Two Saturn AL-41F1 afterburning turbofan engines (future upgrade to Izdeliye 177s)
• Top Speed: Mach 2.0 (1,320 mph, 2,130 km/h) at altitude
• Range: 2,175 mi (3,500 km)
• Service Ceiling: ~65,617 ft (20,000 m)
• Loadout: Internal 30mm GSh-30-1 cannon and various internal and external missiles and guided bombs, including the long-range R-77M and extended-range R-37M air-to-air missiles, short-range R-74M2 missiles, and precision-guided munitions like KH-59MK2 cruise missiles and KAB-500 guided bombs
• Aircrew: 1

Russia Keeps Losing Su-57s—and Can’t Easily Replace Them

Any loss of a Su-57, or even significant damage to one, is a serious matter. The Kremlin has struggled with the production of the aircraft, and the state-owned United Aircraft Corporation (UAC) and its export Rosoboronexport subsidiary have largely failed to find export customers for the multirole fighter. Altogether, Russia is believed to have built fewer than three dozen of the aircraft, with an estimated price tag of $150 million per unit.

Nor was the destruction of the Su-57 in Astrakhan the first recent loss of the aircraft. It comes after two other Su-57s were damaged in a Ukrainian drone strike in May, and another crashed near Moscow during a routine training flight in late July—meaning that Russia probably operates fewer of the aircraft now than it did at the beginning of the year.

According to eyewitness reports, the pilot in the July incident was able to safely eject, and there were no casualties on the ground. That aircraft was conducting a training flight in the Odintsovo district of the Moscow region and crashed near the town of Zvenigorod, approximately 65 km (40 miles) west of Moscow’s central district.

About the Author: Peter Suciu

Peter Suciu regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. He has contributed to dozens of newspapers, magazines, and websites over a 30-year career in journalism, including Forbes and Clearance Jobs. He is based in Michigan. You can follow him on Twitter: @PeterSuciu. You can email the author at Editor@nationalinterest.org.

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