No person transported by the owner or operator of an aircraft or a watercraft as a guest without payment for such transportation, shall have a cause of action for damages against the owner or operator for injury, death or loss, in case of accident, unless the accident was intentional on the part of the owner or operator or caused by the gross negligence or intoxication of the owner or operator. As used in this section:

1. (1) “Payment” means a substantial benefit in a material or business sense conferred upon the owner or operator of the conveyance and which is a substantial motivating factor for the transportation, and it does not include a mere gratuity or social amenity.
2. (2) “Gross negligence” refers to negligence which is materially greater than the mere absence of reasonable care under the circumstances, and which is characterized by conscious indifference to or reckless disregard of the rights of others.

[1961 c.578 §2 (30.115 enacted in lieu of 30.110 and 30.120); 1979 c.866 §7]