THE company in charge of the proposed floating heliport on Sydney Harbour says it has conducted independent tests showing noise generated from its helicopters is ''basically imperceptible'' to the nearest residents.
To calm angry residents, James Guest, a director of Newcastle Helicopters, paid acoustic consultants to conduct noise tests on Wednesday morning - something, he said, he was not required to do to secure a licence.
Mr Guest said two helicopters flew at low altitude over the harbour east of Fort Denison - the main site where the helicopter service will operate. The acoustics consultants from Airport Friendly Solutions stood with measuring devices on a balcony of a Kirribilli apartment and outside a house at Cremorne Point.
There has been a growing public outcry against the harbour helicopter service, which the government approved without preparing an environmental impact statement, testing for noise, consulting the public or putting it to tender.
The two helicopters - one with ''quiet technology'' and one a standard model - both registered fewer than 60 decibels, levels similar to a quiet office, according to Mr Guest. He said they planned to do a ''demonstration flight'' next month so residents and users of the harbour can see how quiet the helicopters will be.
However, the demonstration flights will be taking off and landing on a barge different to the glossy artist impressions on the Newcastle Helicopters website.
''It will bear some resemblance to the artist's impression, but [the image] is more of a second evolution of the heliport,'' Mr Guest said.
The barge, about 40 metres long, is sitting in Rozelle Bay awaiting government approval. It is an ''older vessel'', not self-propelled, and made of concrete.
This appears to contradict a statement from the Deputy Premier, Andrew Stoner, last month that the vessel would be ''an innovative new flat-top powered barge''.
Opposition to the heliport is rising, with a coalition of residential and recreational groups who use the harbour for water-based activities meeting on Saturday to plan a campaign against the planned operation.
Fairfax Media understands the meeting will be chaired by solo round-the-world yachtsman and Clean Up Australia founder, Ian Kiernan. Also joining the chorus of opposition is a prominent Sydney QC, Robert Stitt, who has written to the north shore MP and Health Minister, Jillian Skinner, labelling the proposal an ''outrage''.
''I do not remember any previous government decision which has sparked such spontaneous anger and outcry amongst the community,'' said Mr Stitt, who is the chairman of the Lavender Bay precinct committee.
The Environmental Defenders Office will investigate the approval process of the Department of Roads and Maritime Services which issued the heliport licence.
One of Australia's largest helicopter tourism operators has expressed concern about inadequate environmental assessment of the proposal.
"This has the potential to turn a million Sydney harbourside residents against helicopters,'' said Guy Maine, the managing director and chief pilot of Heli Experiences. Mr Maine said his company, which carries about 15,000 passengers a year, would not use the heliport until proper testing has been carried out.