As used in this chapter:
(1) “Aircraft” means any contrivance invented, used, or designed for the navigation of or flight in the air, and that is required to be registered under the laws of the United States;
(2)
(A) “Controlled substance” means a drug, substance, or immediate precursor in Schedules I through VI.
(B) The fact that any person charged with a violation of this chapter is or has been entitled to use that drug or controlled substance under the laws of this state does not constitute a defense against any charge of violating this chapter; and
(3) “Intoxicated” means influenced or affected by the ingestion of alcohol, a controlled substance, any intoxicant, or any combination of alcohol, a controlled substance, or an intoxicant, to such a degree that the operator's or navigator's reactions, motor skills, and judgment are substantially altered and the operator or navigator, therefore, constitutes a clear and substantial danger of physical injury or death to himself or herself and other persons.