Is that kill ratio of 1 to 10 in neutral territory or Iranian air space where they have air defense support?Unfortunately it's Iranian leadership who is overestimating the value and capabilities of this Aircraft and they are miscalculating the cost efficiency of such a Fighter Jets compared to a more expensive more capable fighter
Fact is if your producing a fighter that you know will at best have a 1 to 10 kill ratio (meaning one 4.5Gen enemy kill for every 10 F-5 kosar losses) then that means when calculating the cost everything from the cost of the Aircraft to maintenance hours required per flight hour, to cost of storage and fueling equipment to cost of pilot training and maintenance crew training to the cost of the onboard weapons requirements all need to get multiplied by 10! So it's not as simple as saying this Fighter is 10Milltion USD and 10 of them would be $100M vs a single Su-35 that would cost me $100 million USD. (And I'm not saying that Iran should purchase fighters simply that the fighters we produce ourselves at home need to be far more expensive and more capable fighters because with manned fighters a cheaper fighter jet doesn't necessarily come out cheaper in the long run)
At the end of the day this is an Aircraft that can't even fly 300km outside Iranian Airspace with ordinance on board.
The F-5E is a very light fighter jet with very limited thrust and range. This is a fighter jet with approximately half the empty weight of an F-16 and with those small weak engines there really isn't much thrust to leave room for any major design changes or improvements that would actually be worth the cost.
Fact is J-85 (owj) engines are NOT good engines for use on an armed manned fighter jet especially not in a country as big as Iran.