Sales tax: exemptions; purchase of certain aircraft and aviation equipment; exempt. Amends sec. 4x of 1933 PA 167 (MCL 205.54x).

HB 4119 exempts sales of large aircraft (over 6,000 pounds) and certain parts/materials attached to them from Michigan's sales tax when used by commercial airlines for passenger or cargo transport. It specifically applies to domestic air carriers operating under federal aviation rules, covering both new aircraft purchases and maintenance-related transactions. Key conditions include requiring aircraft to leave Michigan within 15 days of temporary use (e.g., for evaluation or repairs) and ensuring they were not based or registered in Michigan before or after the transaction. This policy change directly affects commercial airlines and aircraft sellers, reducing tax liability on qualifying equipment purchases and maintenance services.