An Air Canada Boeing 787-9, registration C-FNOH, was in route at FL360 about 400nm northeast of San Antonio on flight AC-2340 from San Antonio, TX (USA) to Toronto, ON (Canada) with two crew members when the crew got “Nitrogen Generation System” (NGS) and “Slat Position Sensor” Status signals.
The crew consulted with maintenance and opted to return to San Antonio, where the plane safely landed about 2 hours after departure.
According to the Canadian TSB, maintenance replaced the NGS valve actuator and the left-hand leading-edge transducer.
