Comments by "Chef Chaudard" (@chefchaudard3580) on "How Long Does Russia Have Left? Number of Tanks, Each Type, and Their Decline This Year" video.

It maybe the case older tanks are equipping conscripts units. Their former tanks being sent to Ukraine. Remember that conscription is still running and there are no conscripts on the frontline. Only professionals, volunteers and mobilized men. And what is difficult is to estimate the number of tanks that wear out. A wore out engine or gearbox needs to be replaced with either a new built engine (meaning that industry must be able to build new engines for refurbished, new and wore out tanks, which is a probable bottleneck), one from stock (witch are probably depleted after 2 years of war)… or one cannibalized from an old tank… which is now unusable.
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