Section 51L. All contracts for the acquisition, establishment, construction, enlargement, improvement, protection, equipment, maintenance or operation of airports or other air navigation facilities, made by an airport commission itself or through the agency of the Massachusetts aeronautics commission, shall be made pursuant to the laws of the commonwealth governing the making of like contracts; provided, however, that where such acquisition, establishment, construction, enlargement, improvement, protection, equipment, maintenance or operation is financed wholly or partly with federal moneys the airport commission, or the Massachusetts aeronautics commission as its agent, may let contracts in the manner prescribed by the federal authorities, acting under the laws of the United States, and any rules or regulations made thereunder, notwithstanding any other law of the commonwealth to the contrary.