Those fighting what they say are huge changes in aircraft noise above their neighbourhoods believe they have won an important battle.

More than 200 central Auckland residents - from Mt Eden, Epsom, Royal Oak, One Tree Hill, Onehunga, Mangere Bridge and Remuera - packed out a community hall last week to hear from those behind a flight path trial which they say has transformed their previously quiet streets into something else entirely.

The year-long "SMART" trial began last November and is being run by Auckland Airport, Airways New Zealand and Air New Zealand with the aim of reducing fuel use and carbon emissions.

It has been the subject of much complaint but the airport maintains there has been little discernable impact on noise levels, a message its spokespeople reiterated at the Royal Oak Baptist Church meeting.

The airport's aeronautical operations manager, Judy Nicholl, says the trials have been conducted within its parameters of 10 flights a day, with only three airlines participating between 7am and 10pm.

But many residents have found their lives have been negatively affected by louder plane noise and turned out in force to share their experiences. Epsom resident Lorraine Clarke has been at the forefront of protest and says those behind the trial will be in no doubt as to the depth of feeling in the community.

"I'm very happy with how it went. When you get a whole lot of people together who don't look like loop heads it is very hard to ignore."

The airport has commissioned acoustics firm Marshall Day to monitor noise and assess complaints.

It has put a $30,000 noise monitor into one Epsom property and is about to set up two more.

Marshall Day acoustic consultant Chris Day told the crowd its monitoring showed there was little difference between the new trial flight paths and those which have been in operation for nearly 15 years.

"It is slightly louder, but one to two decibels is not detectable and three to four only just perceptible."

But complainants are not buying the airport's explanations.

One Buckley Rd resident said she has lived in the Epsom street for decades.

She said an increase in flight activity in the past year had affected her mental health.

"During the last summer I noticed an extraordinary increase in the number of flights and at a lower altitude above my house.

"On some occasions they were very, very low over over my house, I thought they were going to crash in my garden.

"I wish there was a computer game so I could shoot them down."

Others also expressed dismay at the way the trial had been run, the lack of sound monitoring along the trial route and poor communication with residents.

Epsom resident Toni Walker said: "We are residents, not experts. The onus should be on you to prove you can run your business without impacting our lives."

Remuera resident Kevin Kenay said: "It's all about airline profits but what we have got here is aural pollution. This is meant to be a liveable city, we are blessed with an airport next to an ocean, they can do their fiddling over the water.

"We need 100 monitors, that way we will know who is talking crap and who isn't."

Ms Nicholl said the communication lines are now fully open.

"We appreciate the opportunity to engage and take away the feedback.

"When things get that technically involved it takes a while to analyse."

The trial ends next month and will be reviewed in February.