An Air India flight bound for Delhi experienced a sudden loss of hydraulic power at 36,000 feet, triggering what aviation investigators classify as an "altitude upset," a rare and serious in-flight emergency in which an aircraft deviates from its intended flight path or attitude. According to an incident report, the pilot-in-command, who was serving as the pilot monitoring during the flight, later tested positive for a psychoactive substance.

The dual findings, a critical mechanical failure and a positive drug screening involving the same flight, have drawn attention to Air India's operational safety culture at a time when the airline is already under scrutiny following recent incidents.

A Failure With Little Room for Error

Hydraulic systems are essential to an aircraft's ability to maneuver. They power flight controls, including ailerons, rudders, elevators, landing gear, and brakes. A total loss of hydraulics at cruising altitude is considered among the most dangerous scenarios a flight crew can face, since pilots may be left with severely limited or no ability to control the aircraft through conventional means.

According to the incident report, all hydraulic systems failed within seconds while the aircraft was cruising at 36,000 feet, a phase of flight where pilots typically have little time to react to sudden system failures. The result was an altitude upset, a term used when an aircraft unexpectedly departs from its intended pitch, bank, or airspeed parameters, potentially placing enormous stress on the airframe and crew.

Aviation safety experts note that incidents of total hydraulic failure are exceedingly rare in modern commercial aircraft, which are typically engineered with redundant, independent hydraulic systems specifically to prevent a single point of failure from disabling flight controls entirely. That all systems reportedly failed within seconds suggests investigators will need to scrutinize not just the immediate mechanical cause, but whether maintenance oversight, system design, or inspection protocols played a role.

The Drug Test Finding

The incident report also indicates that the pilot-in-command, who was functioning as the pilot monitoring, tested positive for a psychoactive substance. The pilot monitoring is responsible for overseeing instruments, communications, and cross-checking the flying pilot's actions.

Commercial aviation regulators worldwide, including India's Directorate General of Civil Aviation, maintain strict zero-tolerance policies for psychoactive substances among flight crew, given the life-or-death responsibilities pilots carry. Random and post-incident drug testing is a standard safeguard designed to catch violations of these policies. The fact that this pilot's test surfaced in the aftermath of a separate emergency raises questions about whether routine screening protocols are sufficiently robust to identify problems before they endanger flights.

Questions for Oversight

Taken together, the two findings present regulators and Air India with a dual concern: one technical, one human. Safety investigators will likely need to determine whether the hydraulic failure was purely mechanical or whether human factors, including the crew's response time and decision-making, played any role in how the altitude upset was managed and resolved.

The incident is also likely to renew scrutiny of Air India's broader safety culture. The airline, which has undergone significant ownership and operational changes in recent years, has faced repeated questions about maintenance standards, crew training, and regulatory compliance as it works to modernize its fleet and operations.

Aviation safety analysts widely agree that the redundancy built into modern hydraulic systems exists precisely to prevent scenarios like this one, meaning a total failure demands a rigorous, transparent investigation into whether maintenance lapses or design flaws were responsible.

For passengers and regulators alike, the case underscores a fundamental principle of aviation safety: it depends on multiple, overlapping layers of protection, including mechanical redundancy, rigorous maintenance, and a fit, unimpaired flight crew. When more than one of those layers appears compromised on the same flight, the margin for error narrows considerably.

Authorities have not yet detailed what disciplinary or corrective action will follow, either regarding the pilot's drug test result or the hydraulic system failure. Given the severity of both findings, aviation observers expect the incident to draw sustained attention from India's civil aviation regulator as it weighs whether existing oversight mechanisms, from maintenance checks to crew drug testing, are sufficiently robust to prevent a similar convergence of failures in the future.