Extends the expiration date for a sales tax exemption for certain aviation jet fuel

SB 1685 extends Missouri's sales tax exemption for aviation jet fuel used by interstate airlines, allowing carriers to avoid paying state sales tax on qualifying fuel purchases up to $1.5 million annually. This exemption directly affects commercial airlines transporting passengers and cargo across state lines, with tax revenues from the exemption directed to the aviation trust fund (capped at $10 million yearly). The bill updates the expiration date of this existing policy from 2033 to December 31, 2043, maintaining the same annual tax cap and refund mechanisms for overpayments. The change provides continued tax relief for the aviation industry without altering the exemption's core structure.