Texas Tax Code - TAX § 163.005. No Imposition of Tax Following Out-of-State Use

(a) No tax is imposed under Subchapter D, Chapter 151,  1 with respect to an aircraft that is brought into this state if the aircraft is predominantly used outside of this state for a period of one year beginning on the later of:

(b) For purposes of this section, an aircraft is predominantly used outside of this state if more than 50 percent of the aircraft's departures are from locations outside of this state.