A HUGE search effort continues this morning as hopes fade for six people on board a missing vintage biplane.
The aircraft disappeared on Monday, somewhere over the Jimna Range which stretches south and west of Imbil.
Searchers confirmed late yesterday that they were concentrating on a 20 by 25 nautical mile area centred on the Borumba Dam.
Fourteen helicopters and two fixed-wing aircraft were involved in the intensive national search effort yesterday.
Pilot Des Porter and his vintage De Havilland Dragon passenger biplane were well known in the Gympie and Sunshine Coast regions.
Gympie police yesterday confirmed that the search was continuing but was discontinued as light began to fade after 5pm.
"They're trying to get everyone back on the ground and they'll be starting again in the morning," Gympie Police Sgt Vic Tipman said yesterday.
He said the search was being directed from Maroochydore and police had set up a forward control post and fuel depot at Kenilworth.
Three Australian Maritime Safety Authority search and rescue co-ordinators yesterday flew to the Sunshine Coast to direct the search for the missing 1934 aircraft.
No sightings were reported from yesterday's search.
The big air search, now over a 500sq nautical mile area centred on Borumba Dam, will be supported by a co-ordinated land expedition if a sighting is made.
Pilot Des Porter's last known communication was a radio call answered by AGL Action Rescue helicopter crewman Rick Harvey about 2pm Monday.
An emergency position indicating EPIRB signal from the aircraft was lost about the same time.
The 16 aircraft involved in yesterday's search included all three AGL Action Rescue choppers, the Brisbane-based Emergency Management Queensland helicopter, the Gold Coast-based Careflight helicopter and a Dornier fixed-wing aircraft with infra-red capabilities.
A number of smaller privately owned helicopters also joined the search yesterday.
Weather conditions improved in the area yesterday, raising speculation that Mr Porter may have experienced navigation difficulties in Monday's cloudy and rainy conditions.
All attempts to re-establish contact with Mr Porter or his five passengers were unsuccessful.
Police in Maroochydore yesterday confirmed that a ground search would not occur until air searchers find some sign of the plane.
"It is difficult country so we will be looking at the capabilities of the people we are going to put in there.
"But there's no point in rushing off until we can get some location."
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