Majority of commercial operators using water injection ceased doing so in the sixties. Except in the most extreme high/hot conditions, the incremental takeoff thrust settings enabled were ultimately deemed less than advantageous when offset by the reduced payload (the weight of the water you had to carry was part of…

Cost of the retrofit amortized over the anticipated future life expectancy doesn't provide a payback. Of course - the anticipated useful life has been exceeded 2 or 3 x over. Had it been executed when first proposed - - we would have been loads of bucks ahead.