(a) In Class 2 municipalities, the gross proceeds from the sale or sales of materials or supplies to any person for the use in fulfilling a contract for the painting, repair, conversion, modification, or reconditioning of aircraft of 30,000 pounds gross weight or greater shall be exempt from municipal sales and use tax. Notwithstanding the foregoing, the exemption provided in this section shall only apply to those materials and supplies which enter into and become a component part of those aircraft.
(b) The exemption provided in this section shall be applicable to all sales occurring on and after October 1, 2003.