Indian aviation regulator DGCA has directed SpiceJet, Vistara and Air India to inspect their Boeing 737 aircraft after the US Federal Aviation Administration (FAA) on Friday issued an emergency airworthiness directive (AD) for all the mentioned aircraft that have not flown for more than seven days at a stretch.

The emergency directive was “prompted by four single-engine shutdowns” that happened due to compromised air check valves in the engines of the certain B737 aircraft, said the Federal Aviation Administration (FAA) in its emergency directive.

As per the FAA directive, airlines are instructed to inspect their B737 aircraft that have not flown for seven days or more and the ones that have operated not more than 10 flights after return to service.

A senior DGCA official said the Indian regulator has asked for compliance from the Indian carriers SpiceJet, Vistara and Air India Express.

Another Directorate General of Civil Aviation official said inspection of some of the Indian aircraft has already been done by their owner airlines.

Boeing, in a statement, said, “Out of an abundance of caution, Boeing has advised operators of 737 Classic airplanes (series -300 to -500) and Next-Generation 737s (series -600 to -900) to inspect an engine valve for corrosion. With airplanes being stored or used infrequently due to lower demand during the COVID-19 pandemic, the valve can be more susceptible to corrosion. Boeing is providing inspection and replacement information to fleet owners if they find an issue.”

SpiceJet spokesperson said, “The FAA AD applies to a small number of B737s in our fleet that hasn’t yet completed ten cycles on return of aircraft to service. They are being inspected. The majority of our planes have completed ten cycles already and are not affected by this AD.”

On this matter, Vistara spokesperson said, “Vistara is in compliance of the directive. The inspection of the engines of all six of our B737 aircraft has already been completed.”