Air India pilot's reported cannabis test: What it can and can't tell investigators

A review , externalby aviation-medicine specialist David Newman for Australia's Transport Safety Bureau reached a similar conclusion. Cannabis affects behaviour, cognition and psychomotor performance in a dose-dependent way, and complex tasks such as flying are particularly sensitive. The review also found evidence of residual effects lasting up to 24 hours.The science has become more complicated, however, as cannabis use has become more widespread and the potency of cannabis products has increased in many parts of the world.A 2022 randomised clinical trial, external led by Thomas Marcotte at the University of California San Diego tested 191 regular cannabis users. Those who smoked THC performed worse on a simulated driving task, but the researchers found that impairment could not be inferred from the THC content of the cannabis, the users' previous experience or their blood THC concentration. The drug initially impaired performance, but after about four-and-a-half hours, those who had taken it were performing about as well as people who had not received the active drug.That finding matters enormously for aviation testing.A positive test can show that THC is present, but not necess...