A Delta Air Lines Airbus A220-300 bearing the registration N301DU, carrying out flight DL829 from Ted Stevens Anchorage International Airport (ANC) to Seattle-Tacoma International Airport (SEA) suffered a mechanical issue upon final approach. According to The Aviation Herald, the jet was on final approach to Runway 16R when the crew initiated a missed approach and advised the tower that they needed to do some troubleshooting on a maintenance issue.