A Russian Su-57 fighter jet reportedly exploded last week at an airfield in southwestern Russia, according to claims made by Ukraine.
If confirmed, the incident would represent another setback for the aircraft that Moscow considers the most advanced in its military fleet.
Ukraine’s Defence Intelligence (GUR) said on Monday that the incident occurred on October 29 at Akhtubinsk airfield in the Astrakhan region, as the Su-57’s engines were being started.
Russia describes the Su-57 as its most advanced and radar-evading aircraft, presenting it as a fifth-generation fighter comparable to the American F-35 and F-22.
However, many Western aviation experts have questioned whether the aircraft truly meets the stealth technology standards associated with this category.
Moscow has used Su-57 aircraft to carry out long-range strikes during its war against Ukraine. However, analysts have described their battlefield performance as disappointing, while noting that Russia has shown little willingness to risk these expensive aircraft, of which it has only a limited number.
According to the International Institute for Strategic Studies (IISS), a British defence analysis organisation, Russia had approximately 21 Su-57 aircraft in service at the beginning of 2026. Further production has progressed slowly, partly because of the demands the war in Ukraine has placed on Russia’s defence industry.
Ukrainian estimates put the cost of one Su-57 at approximately $150 million.
The GUR has claimed that the engines installed in these aircraft could “explode or suffer catastrophic destruction” if supplied with poor-quality aviation fuel. However, the agency has not directly linked this potential problem to the reported explosion at Akhtubinsk.
Ukrainian officials say Russia has been forced to rely more heavily on imported aviation fuel because of Ukraine’s ongoing drone campaign against Russian oil refineries. These attacks aim to restrict Moscow’s ability to finance its war, while US President Donald Trump has reportedly pressured Kyiv to halt them.
