Russia admits it will not be able to mass produce fighter plane to challenge US F-35

Business Insider:

Russia announced earlier this month that the Su-57, its proposed entry into the world of fifth-generation stealth-fighter aircraft, would not see mass production.

"The plane has proven to be very good, including in Syria, where it confirmed its performance and combat capabilities," Russian Deputy Defense Minister Yuri Borisov said on Russian TV on July 2, as reported by The Diplomat.

But despite Russia's nonstop praise for the plane and dubious claims about its abilities, Borisov said, per The Diplomat: "The Su-57 is considered to be one of the best aircrafts produced in the world. Consequently, it does not make sense to speed up work on mass-producing the fifth-generation aircraft."

Justin Bronk, a combat-aviation expert at the Royal United Services Institute, told Business Insider that Borisov's comments "could be charitably described as an unreasonably optimistic reason why they stopped production."

Basically, Borisov said the plane is so much better than everything out there that Russia doesn't need to build it — a claim Bronk finds unlikely.

Instead, Russia will stick to what it's good at, with upgraded fourth-generation aircraft in service instead of the Su-57, which was originally meant to replace the older fighters.

The Su-57, a plane designed to function as a killer of US F-35 and F-22 stealth jets with an innovative array of radars, saw a brief period of combat over Syria, but the deployment lasted only days and didn't pit the jet against any threats befitting a world-class fighter.
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A senior stealth scientist recently told Business Insider that though the jet claimed a stealthy profile, it had glaring and obvious flaws. A 2016 report from IHS Jane's said the jet was fifth-generation "in name only."
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The jet was supposed to be more maneuverable than the F_35, but its lack of stealth made it very unlikely it could ever get close enough to engage in a dogfight.   Beside it deficiencies, I do not think the Russian economy is strong enough to pay for a large production run of this aircraft.  Russia's GDP is less than that of the state of Texas.