A full-scale aerial search for a missing plane with six people on board will begin at first light in the Sunshine Coast hinterland on Tuesday.
The pilot of the missing 1934 De Havilland DH84 Dragon biplane had been raising funds for charity before the vintage craft vanished in southeastern Queensland.
Des Porter, 68, was giving scenic flights in his prized red 1930s biplane at an airshow in central Queensland on Monday morning, according to the organiser of the Monto Fly-In.
He is one of six people on board the 1930s de Havilland DH84, which left the town of Monto, 180 kilometres west of Bundaberg, shortly after 11am (AEST).
It's believed the other passengers were two couples around retirement age and Mr Porter's partner.
The red biplane left Monto on Monday en route for Caboolture and contacted air traffic services in Brisbane requesting assistance before activating an emergency beacon about 2.45pm.
But the beacon was no longer being detected late on Monday and Rescue Coordination Centre Australia could not contact the pilot.
Queensland Police said an air search was conducted in the area west of Imbil by the Australian Maritime Safety Authority, but was later suspended due to poor conditions.
A search of the terrain around Imbil will continue at first light on Tuesday.