On Tuesday, a SpiceJet Boeing 737-8 Max plane was grounded after returning to Chennai minutes after taking off for Durgapur, West Bengal, prompting an investigation by the aviation regulator.

After take-off around 7.40 p.m., the aircraft’s number two engine shut down, forcing a return, according to Chennai airport officials. The oil filter bypass lights on engine number two flashed during the climb, according to an official. “According to the quick reference handbooks, the pilot in command performed an in-flight shutdown of engine number two… Following the completion of the checks, the pilot requested a priority landing of the aircraft…” Around 7.45 p.m., the plane touched down.

“Due to a technical issue, SpiceJet flight SG-331 from Chennai to Durgapur returned to Chennai after taking off on May 3 [Tuesday].” “The plane landed safely,” said a SpiceJet spokesperson.

The air turnback on the Durgapur-bound flight is the second since the Boeing 737 MAX aircraft ban was lifted. In December, a SpiceJet flight bound for Kolkata was forced to return to Mumbai after one of its engines failed.

Boeing 737 MAX aircraft began flying again in December 2020, two years after they were grounded worldwide following the fatal crashes of Lion Air in 2018 and Ethiopian Airlines in 2019. The crashes were blamed on a faulty flight handling system designed to keep the plane from stalling as it ascended. The automated system was discovered to have pushed the plane’s nose down.

Boeing was later ordered by US aviation authorities to overhaul the planes and implement new pilot training protocols. In India, the Boeing 737 MAX ban was lifted in 2021.

The regulator, the Directorate General of Civil Aviation (DGCA), barred 90 SpiceJet pilots from flying Boeing 737 Max aircraft until they completed the required training, citing simulator training issues. The airline has barred the pilots from flying until they have undergone retraining. These pilots are still available to fly other Boeing 737s.