Four people - including pilot Ashley Jenkinson - were killed in a fatal mid-air collision between two Sea World helicopters outside the Gold Coast theme park on January 2, 2023.
Earlier evidence revealed Mr Jenkinson, 40, returned a post-mortem positive test for cocaine metabolites.
Civil Aviation Safety Authority (CASA) was quizzed about drug and alcohol rules for aviation operators at the ongoing inquest into the fatal crash in Brisbane on Monday.
CASA's national manager for regulatory services Niels Bunte was asked how the rules were applied to Drug and Alcohol Management Plans, which set out how companies test "safety-sensitive" staff such as helicopter pilots.
He confirmed that operators like Sea World Helicopters could require daily alcohol breath tests before flights under their own policies and arrangements.
But civil aviation safety regulations did not specify how often pilots must be tested for illicit drugs, beyond trigger points such as CASA random tests, new hires, serious incidents and suspected impairment, Mr Bunte said.
"There is no prescribed frequency for routine drug testing in the regulations," Mr Bunte told coroner Carol Lee.
"The legislation identifies when testing must occur but not how often an operator has to run those checks."
He told the court CASA expected operators to ensure "all individuals conducting safety-sensitive activities are managed appropriately" under their drug and alcohol plans.
The inquest has heard that Sea World Helicopters' written drug and alcohol plan, and its later revisions, were intended to comply with the regulations and could be audited by CASA.
Witnesses earlier told the inquest they saw Mr Jenkinson take cocaine at a New Year's Eve party before the collision.
Mr Jenkinson was flying an EC130 helicopter with six passengers when it collided mid-air with another Sea World aircraft near the theme park and plunged about 40 metres onto a sandbar.
He was killed along with British newlyweds Ronald and Diane Hughes, aged 65 and 67, and Sydney mother Vanessa Tadros, 36.
The second helicopter, flown by pilot Michael James, made an emergency landing on the same sandbar.
Nine people in total were injured, including Ms Tadros's son Nicholas, who spent months in hospital and lost his leg.
The inquest is examining pilot impairment, cockpit visibility, Sea World Helicopters' safety systems and CASA's oversight of drug and alcohol use in the industry.
