2024年8月4日，印度航空一架A320客机在从普吉特飞往德里的途中突然下降约91米，造成人员伤亡[1]。这架航班搭载137名乘客和8名机组人员，事件中13名乘客和4名机组人员受伤[1]。报道称机长在毒品筛查中大麻检测呈阳性，但官方尚未正式确认这一信息[1]。
作为应对措施，印度航空宣布将立即对全体飞行员进行违禁物质测试，这比原有规定更为严格——原先的要求仅为至少10%的飞行员接受随机筛查[1]。不过，安全调查人员面临的一个关键难题是，大麻检测的阳性结果本身存在局限性[1]。研究表明，大麻使用后24小时内仍可检测到四氢大麻酚（THC），但这一结果既不能可靠地确定使用时间，也不能直接证明飞行员在飞行时处于受损状态[1]。
加拿大在2018年大麻合法化后制定的规定对飞行机组人员的要求为：在值班前至少28天内不得使用大麻[1]。
An Air India Airbus A320 experienced a sudden altitude drop of approximately 91 meters (300 feet) while en route from Phuket to Delhi on August 4, 2024, resulting in injuries to 13 passengers and 4 crew members [1]. The aircraft was carrying 137 passengers and 8 crew members at the time of the incident [1]. Reports indicated that the captain tested positive for cannabis in a drug screening, though Indian authorities have not formally confirmed this result [1].
The positive test result, however, presents significant limitations for aviation investigators [1]. While tetrahydrocannabinol (THC), the active compound in cannabis, can remain detectable in the body for up to 24 hours after use, this detection does not reliably establish when the substance was consumed or whether the pilot was actually impaired during the flight [1]. In response to the incident, Air India announced it would immediately conduct drug screening for all its pilots, expanding beyond the previous requirement of random testing for at least 10 percent of the flight crew [1]. For context, Canada has required flight crew members to abstain from cannabis use for at least 28 days prior to duty since the substance's legalization in 2018 [1].