The Nigerian Civil Aviation Authority (NCAA) has written a letter to all airline operators, directing them to comply with Emergency Airworthiness Directive (EAD) on Boeing 737 aircraft identified by the US Federal Aviation Administration (FAA).
The letter referred to the compliance to correct technical issues concerning these particular aircraft types and was directed to all airlines that operate Boeing Company Model 737-300, -400, -500, -600, -700, -700C, -800, -900, and -900 ER series of airplanes.
The letter was signed by the General Manager in charge of Air Operator Certificate and Safety, Godwin Balang on behalf of the Director General of NCAA, Captain Musa Nuhu.
The letter stated, “The authority has reviewed the FAA AD2020-16-51 vis-à-vis the COVID-19 pandemic lockdown that necessitated the storage of B737 aircraft and made a determination as follows: That compliance with the FAA emergency AD (Airworthiness Directive) must be carried out by affected operators of Boeing 737 aircraft in Nigeria as required by the AD and all affected operators should submit evidence of compliance with the FAA AD2020-16-51 to their Principal Maintenance Inspector (PMI) within two days.”
NCAA also directed the airlines should “ensure strict compliance”.
An official of the regulatory body however told newsmen that there was no cause for alarm because everything is under control, remarking that the airlines would comply with the directive.
“NCAA has written to all the airlines operating B737s in the country and directed them to report back to the regulatory agency in two days’ time on their compliance. Any affected aircraft will be thoroughly inspected and proper checks will be carried out.
“It will affect some of the aircraft types while others will not be affected. Nigerian airlines will not feel the impact because not all the aircraft are being operated due to low patronage as a result of the recent resumption due to Covid-19,” the NCAA official explained.
According to the FAA, “This emergency AD was prompted by four recent reports of single-engine shutdowns due to engine bleed air fifth stage check valves being stuck open. Corrosion of the engine bleed air fifth stage check valve internal parts during airplane storage may cause the valve to stick in the open position. If this valve opens normally at takeoff power, it may become stuck in the open position during flight and fail to close when power is reduced at top of descent, resulting in an unrecoverable compressor stall and the inability to restart the engine.
“Corrosion of these valves on both engines could result in a dual-engine power loss without the ability to restart. This condition, if not addressed, could result in compressor stalls and dual-engine power loss without the ability to restart, which could result in a forced off-airport landing.”
Arik Air, Max Air, Azman Air, Dana Air, Aerocontractors, and Air Peace have in their fleet B737 aircraft, which must be subjected to checks to ensure their continued airworthiness.
