In all cases where a political subdivision has issued any bonds for the purpose of investigating, surveying, planning, acquiring, establishing, constructing, enlarging, equipping, or improving any airport, or other air navigation facility, or site therefor, or to meet the cost of structures or other property incidental to their operation, whether such airport or other air navigation facility was termed under the law existing at the time of the issuance of such bonds an airport, a landing field, a landing strip, an aviation field or a flying field, or has incurred any other indebtedness, or entered into any lease or other contract in connection with the acquisition, establishment, construction, ownership, enlargement, control, leasing, equipment, improvement, maintenance, operation or regulation of any such airport or other air navigation facility, or site therefor, or structure or other property incidental to its operation, the proceedings heretofore taken in all such cases are in all respects validated and confirmed. Any bonds already issued thereunder are validated and made legal obligations of such political subdivision and the political subdivision is authorized and empowered, pursuant to such proceedings, to issue further bonds for such purposes up to the limit fixed in the original authorization thereof, without limitation of the general power granted in this chapter to all political subdivisions in this State, which bonds when issued shall be legal obligations of the political subdivision according to their terms.