From Curt Lewis Newsletter:
The Aviation Herald
Incident: Sunstate DH8D at Brisbane on May 13th 2021, unsafe gear
By Simon Hradecky, created Thursday, May 13th 2021 12:45Z, last updated Thursday, May 13th 2021 12:45ZA
Sunstate de Havilland Dash 8-400 on behalf of Qantas, registration VH-QON performing flight QF-2420 from Newcastle,NS to Brisbane,QL (Australia) with 64 passengers and 4 crew, was on approach to Brisbane's runway 19L descending through about 1800 feet MSL when the crew initiated a go around indicated they had problems with their gear extension, they needed to do a manual gear extension. The crew subsequently entered a hold while working additional checklists after the manual extension did not clear the unsafe indication. About one hour after aborting the first approach the crew indicated they needed full emergency services and engineering on stand by, they requested an ILS approach and were cleared for the ILS approach to runway 19R. The passengers were instructed to brace for landing. The aircraft landed safely on runway 19R about 70 minutes after aborting the first approach and stopped on the runway. The landing gear was secured before the aircraft was towed to the apron.
The airline reported the landing gear had worked normally, however, a faulty sensor had caused an alert of unsafe gear in the cockpit.