Air India pilot's cannabis test raises questions about what drug tests can really tell us

Reports that an Air India pilot tested positive for cannabis after a flight have raised questions about what such a result can actually tell investigators. On 4 August, an Air India Airbus A320 flying from Phuket to Delhi suddenly lost about 91m (300ft) of altitude, injuring 13 passengers and four crew members. The aircraft, carrying 137 passengers, landed safely in Delhi. Both pilots underwent routine post-flight screening for psychoactive substances. India's aviation ministry said the captain's initial test produced a result requiring confirmatory testing, and that both pilots had been removed from flying duties. Subsequent media reports, citing sources, said the captain tested positive for marijuana in a confirmatory laboratory test. Air India has not confirmed the result, and there is so far no official finding linking any drug test result to the sudden loss of altitude. Even if confirmed, experts note that a positive cannabis test does not necessarily indicate impairment at the time of the incident. Cannabis metabolites can remain detectable for days or even weeks after use, far beyond the window of actual impairment.