(a)
It is unlawful for any person, who is under the influence of an alcoholic beverage or any drug, or the combined influence of an alcoholic beverage and any drug, to operate an aircraft in the air, or on the ground or water, or to engage in parachuting for sport.(b)
No person shall operate an aircraft in the air or on the ground or water who has 0.04 percent or more, by weight, of alcohol in his or her blood.
Source:
Section 21407.1, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=PUC§ionNum=21407.1..