Kenya Airways will be forced to inspect afresh the engines of its 10 Boeing 737 New Generation aircraft after the US aviation regulator warned that they could stall mid-air after being grounded for months.

The Federal Aviation Authority (FAA) said the Boeing 737NG aircraft that have been idle since the outbreak of Covid-19 could form corrosion on the air check valves, an anomaly that can lead to stalling of the two engines when the airplane is flying.

Kenya Civil Aviation Authority (KCAA) Director-General, Gilbert Kibe, said they had received communication from the FAA, adding that the agency will ensure local carriers such as Kenya Airways are in compliance.

Kenya Airways has 10 Boeing 737NG — mainly used for mid-range flights such as the Africa routes — in its fleet of 42.

“We have received communication and Kenya Airways too has the alert. We shall monitor the task,” said Mr Kibe in an interview with the Business daily.

The FAA said the airlines must replace the engine valves ahead of flying if they are corroded.

In a statement last week, Boeing Company, the manufacturer of the planes, said it had advised operators to inspect the aircraft that had been grounded for long or used infrequently in the wake of Covid-19 pandemic.

Boeing reckons that the valves can be more susceptible to corrosion.

Kenya Airways said it was addressing the issue before taking to the skies in a move that will assure passengers of their safety once international flights resume this Saturday.

“KQ has a process and has put measures in place to ensure all its affected aircraft have the recommendation accomplished before they get back to the skies,” said the airline in an e-mail response to the Business Daily.

Kenya Airways normally uses these type of aircraft on Africa routes with higher passenger numbers because of its high capacity compared to the Embraer 190.

The Boeing 737-800 has a flying range of 5,665 kilometres.

KQ grounded its international flights on April 6 after Kenya closed its airspace to passenger planes in order to curb the spread of Covid-19.

The carrier has, however, been operating its fleet of Boeing 787 that it had converted into cargo flight for long-haul services, especially to Europe and Asia.

This is the second time that Boeing has issued an airworthiness directive on this type of aircraft since late last year.

Last September the FAA wrote to Kenya Airways directing it to inspect its fleet of Boeing 737 New Generation aircraft for potential cracks.

The carrier resumed passenger services on international routes last Saturday with 27 destinations having been earmarked. This is half of the routes that the airline was servicing before the Covid-19 pandemic.

KQ reported a Sh12.9 billion loss for the financial year ended December 2019, up from Sh7.7 billion in 2018, with losses attributed to increased cost of operations.

The airline estimates it lost Sh10 billion in the six months to June this year.

The airline, which resumed domestic flights two weeks ago, is now banking on the resumption of the international flights to generate more income and be in a position to meet its financial obligation.