Any city of the second class having population of less than ten thousand (10,000) located in a county having a population of more than thirty-six thousand (36,000) and less than forty-five thousand (45,000) with an assessed tangible valuation of more than ninety million dollars ($90,000,000) which has acquired fee simple title to real estate for use as an airport or flying field and, whenever in the opinion of the governing body of such city such airport or field is no longer needed, suitable, adaptable or feasible, it may discontinue such airport and sell such real estate or any portion, parcel or tract thereof.