The second day of a search for a missing plane has ended unsuccessfully.
An aerobatic plane remains missing after a day of searching the area around the Coromandel Peninsula.
The Acrosport 2, registered to Dariosh Kraidy, 53, of the Auckland suburb of Mt Wellington, went missing after taking off from Ardmore near Auckland at 11.25 am yesterday.
Searchers were buoyed by an aerial sighting of an oil slick off New Chums Beach today, but a police launch that went to the area was unable to locate any wreckage, or even the slick.
Rescue Co-ordination Centre (RCCNZ) spokesman Steve Rendall said the launch was now trawling the area with sonar and would be assisted by the police dive team should anything be found.
An air force Orion had also been searching the northeast coast of Great Barrier Island, but it also failed to find anything.
The area off New Chums was "the area of interest at the moment", Rendall said.
The South African home-built aircraft, registered ZK-DJK, was initially heading in a northeasterly direction toward the Hauraki Gulf when it disappeared from radar shortly after takeoff yesterday.
The aircraft had a range of 350 kilometres and would have run out of fuel by 1.30 pm.
No distress beacon was activated, but RCCNZ launched a search after a friend of the pilot reported concern for his safety.
The Auckland Westpac Trust helicopter yesterday flew to the last known radar position and searched the surrounding area, with an RNZAF P3 Orion searching the Firth of Thames.
Checks were also made of airfields in the region.
Authorities will consider their options overnight as to how the search will progress.
Anyone with sightings of the distinctive blue and white aircraft with twin wings and an open cockpit can contact RCCNZ on 0508 472 269 or the police.