There's about 400 post 1990 aircraft, about 2/3 will be ready to fly. of those you would only want to burn through about 1/3 otherwise the rest of the country is defenseless...
so 400*2/3*1/3 = 88 aircraft that Putin could have blown up as soon as they entered Ukraine airspace with anti-aircraft fire or missiles form every country helping Ukraine free itself from Russian attack.
Its ridiculous... you are worse than Putin at strategy
