The Director of Transportation may appoint, employ, hire, or engage assistants, aides, and employees as necessary for the proper performance of the Director’s duties and functions. The compensation of those assistants, aides, and employees shall be as provided in the Ordinance of Estimates. Subject to the prior approval of the Board of Estimates, the Director also may employ or hire, from time to time, on a temporary basis, by contract, consulting, planning, or designing engineers or other persons possessing technical or specialized skills in connection with the duties, powers, and function of the Department. City Code, 1950, art. 38, §1(d) 1966, art. 31, §1(c)(2nd, 3rd sens.), (d) 1976/83, art. 31, §1(c)(2nd, 3rd sens.), (d) Ord. 51-1678 Ord. 53-786 Ord. 57-1006 Ord. 99-526 Ord. 15-435