Delhi-bound IndiGo flight makes emergency landing in Lucknow after cargo smoke alarm

An IndiGo flight from Agartala to Delhi made an emergency diversion to Lucknow on Tuesday evening after a cockpit warning alert flagged potential smoke in the cargo hold.

Flight 6E6504, an Airbus A320neo carrying 103 passengers and six crew members, landed safely at Lucknow’s Chaudhary Charan Singh International Airport at 6:29 pm. No injuries were reported among the 109 people on board.

During the descent, the pilots transmitted a "7700" transponder code—the international aviation signal used to declare a general mid-air emergency. In response, airport authorities in Lucknow activated their emergency protocols, deploying fire engines, ambulances, and terminal support teams to the runway to meet the aircraft.

Once the plane touched down, passengers were quickly deboarded so that a technical team could inspect the cargo bay. An initial inspection failed to find any physical evidence of smoke or fire, according to an airport source, raising the likelihood that a technical glitch triggered a false alarm.

The aircraft involved in the incident is an Airbus A320neo with the registration VT-ISY, which has been in service with IndiGo for just over five years since its delivery in September 2021.

There were conflicting accounts regarding how the passengers completed their journey to Delhi. Some flight reports suggested the original aircraft was cleared by technicians to depart Lucknow at 9:45 pm. However, aviation sources in other reports indicated that the specific plane had been grounded pending formal clearance from the Directorate General of Civil Aviation, with IndiGo arranging a replacement aircraft to fly the passengers to their destination.

A pattern of false alarms

The scare comes less than two weeks after a nearly identical incident disrupted another flight heading to the capital.

On 3 September, an Air India Express Boeing 737 MAX 8 flying from Varanasi to Delhi was forced to make a precautionary landing in Lucknow after its aft cargo hold smoke alarm was triggered. Just like the IndiGo incident, that flight—carrying 155 passengers—landed safely, and subsequent physical inspections found no trace of smoke or fire.

In March, another Delhi-bound Air India Express flight had to make an unscheduled landing at Lucknow after the pilots suspected smoke inside the cabin.

The recurring false alarms highlight the sensitive nature of cargo-hold detection systems, which are designed to err on the side of caution even when no physical fire is present.