Stuff Digital Edition

Noise annoys for police chopper

Auckland’s Eagle police helicopter is a fixture of the city’s skies – but aviation noise disturbance can have serious and real health impacts. So where, and who, is getting buzzed? reports.

Kate Newton

You’re in bed when it begins: a low, indistinct bass murmur. The murmur sharpens, until it’s an overhead roar. The clangour drifts away, and then it’s back. Circling, fading and building, fading and building with each go-round. Finally, the spiral of noise dies away – for tonight, anyway.

Ask many people in Auckland, and they’ll swear the police helicopter, known as Eagle is above their house, all the time. Flying just about the aviation floor of 305m for built-up areas, it is a literal eye in the sky, arrayed with gyro-stabilised binoculars, infra-red, night vision and a battery of radio equipment to stay in contact with, and often direct, patrol cars on the ground.

Police consider it a vital piece of equipment. In the year to June 2022, it attended more than 7600 incidents, helping to locate an offender in two-thirds of cases.

With a top speed of nearly 300kph, it can get from its base at Pikes Point on the Penrose foreshore to just about anywhere in Auckland in minutes. But the sound it makes in the process isn’t just annoying. Research has shown repeatedly that aviation noise – especially from low-flying aircraft at night – can disturb sleep and have serious health consequences that are magnified the longer and more frequently the noise persists. The Eagle isn’t some shadowy, night-riding twin of Santa Claus – it can’t truly be everywhere, all at once. The Sunday Star-Times has collected and analysed four months of flight data to track where it goes and what it does.

The Air Support Unit – to give the Eagle its proper name – has operated in Auckland since 1988, becoming a round-the-clock operation in 2017. Police do not fly the helicopters themselves – the contract is held by Advanced Flight, which provides civilian pilots and maintenance services. Each pilot is accompanied by two sworn ‘‘tactical officers’’, who operate specialist equipment and communicate with police and other emergency services on the ground.

You won’t find the Eagle on standard aircraft tracking websites – most of these services block radar data for certain aircraft by request – but it’s possible to track all three aircraft that make up the Eagle fleet on ADS-B Exchange, a tracking website based on satellite navigation data.

The Star-Times collected flight data for the three helicopters between February and June. Over that period, the Eagle recorded an average of eight flight hours a day, including about three during ‘‘unsociable hours’’, which the Star-Times has defined as anything between 9pm and 7am.

The data showed the Eagle traversed nearly every part of Auckland (sometimes flying as far north as Northland or south to Waikato), but some areas emerged as clear hotspots.

Other than the base where the helicopter takes off and lands, there are two distinct high-flight areas, O¯ tara and Manurewa, and some lesser hotspots scattered throughout west, central and south Auckland. The map also shows where the helicopter is not. The entire North Shore gets a mostly free pass, along with anything west of the Waita¯ kere Ranges.

For some suburbs, the number of nights the Eagle was active in the area and how long it spent there on those nights were both high.

And when you group this data by deprivation level, it becomes clear that poorer neighbourhoods generally bear the brunt of Eagle helicopter activity, day and night.

Higher crime rates might account for some of the extra Eagle presence in these areas, but not all of it.

The Star-Times matched crime volume to the time spent overhead in each suburb. In the wealthier half of neighbourhoods, there was a relatively strong pattern of flying minutes increasing as crime in the area increases.

In poorer neighbourhoods, the correlation was more tenuous. Not all of the most-visited areas have the highest crime levels and some poorer neighbourhoods with similar crime levels to wealthy ones were visited more frequently.

Ma¯ ngere (a decile 10 neighbourhood – one of the most deprived in the country) and Grey Lynn (decile 3) had similar crime volumes, but the Eagle spent more than twice as long above Ma¯ ngere at night.

This pattern persists across the two groups: while the trend climbs at about the same rate (ie, more crime, more Eagle presence), it starts from a higher base in poorer neighbourhoods.

Police repeatedly refused interview requests for this story.

Asked about this apparent link between deprivation and how frequently the Eagle visits, Auckland City police district operations manager Vaughn Graham said (in a written response): ‘‘Eagle responds to a variety of critical incidents that require police attendance. It deploys where it’s needed.’’

Late at night, somewhere in Takanini, a hatchback has pulled up near a parked digger. Through Eagle’s infrared camera, the heat of the car engine is a bright white glow.

A small, luminescent figure emerges, trudging over to the digger clutching two square canisters. If the helicopter hovering nearby is audible, the figure pays it no attention, focused on siphoning diesel from the machine. The camera zooms out. Two patrol cars are racing to the scene. The person sees them and stumbles back to the hatchback only to be caught by an officer, pushed to the ground, and handcuffed.

‘‘Comms, yeah, we got him in custody,’’ someone says over the radio. ‘‘No issues.’’

A lot of the Eagle’s work appears to be chancing upon such incidents. About 15% of incidents the Eagle assisted with were classed as either burglary and alarms, or suspicious activity and trespass.

Aviation expert and veteran helicopter crash inspector Tom McCready believes this sort of intervention is part of a vital service.

‘‘It’s an asset. I’m surprised they don’t spend more time in other cities,’’ he says. ‘‘If there’s a police pursuit going on and the helicopter turns up overhead and ends that pursuit pretty quickly

because you can track the car, that’s stopping some crazy going down the motorway at 160kph.’’

The benefit doesn’t come cheaply. The three helicopters that make up the Air Support Unit’s fleet are Bell 429s, which chew through an estimated 290-340 litres of fuel an hour. At current prices for Jet

A1 fuel, that would put the fuel costs for the last financial year at $2.8m to $3.3m – about a quarter of the ASU’s $12.4m operating budget. Then there’s the carbon and carbonequivalent emissions: between 2665 and 3156 tonnes – equivalent to a herd of up to 1100 dairy cows.

But the Eagle’s cost can also be measured in decibels. Official specifications for the Bell 429 give 88.9 decibels on take-off, 89.6 decibels when flying directly overhead, and 91.4 decibels landing. Those figures are measured from a distance of 150m, so just under half the altitude the Eagle is usually flying at.

But there’s no doubt that it is still loud, even at 300m or more. In 2020, a university student in one of Wyatt Page’s undergraduate classes at Massey University, frustrated by the noise of the helicopter at night, decided to do some research. Over several months, she measured the volume of the helicopter when it flew over her neighbourhood, day and night. Directly overhead, the volume hit about 70dB. Further away, it peaked at about 55dB.

‘‘Those levels are what you’d deem to be acceptable during daytime when you are awake,’’ says Page, an associate professor of acoustics and human health. ‘‘But they are not acceptable during the night.’’

The WHO global community noise guidelines recommend outdoor noise at night should not exceed an average of 45dB. The WHO’s updated European guidelines recommend aircraft noise at night should not exceed an average of 40dB. Research has shown that noise disturbance can have a huge impact on human health, especially through its effect on sleep. Whereas road noise tends to be a continuous, nonmodulating sound, aircraft noise is ‘‘highly impulsive’’, Page says. ‘‘[It’s] made worse with helicopters, because of their very nature – they come right overhead.’’

David Welch, associate professor of audiology at the University of Auckland, says aircraft noise is also much harder to mitigate. New Zealand’s notoriously flimsy housing doesn’t help.

Page says sudden, loud noises may not wake you up completely but they do trip your fight-flight system, flooding the body with adrenaline and the stress hormone cortisol. ‘‘So what happens [is] ... you get certain people who will wake up feeling completely exhausted, they will feel frightened, and they don’t know why.’’

Society tends to underestimate the impact of noise, Welch says, and even what counts as noise.‘‘If you’re the person who’s about to be murdered, the sound of the helicopter turning up wouldn’t be noise at all, it would be an absolute delight. So I tend to prefer to think of sound as sound, and then noise if you don’t want it. Where you draw the line between wanting and not wanting it is a tricky one.’’

Both Welch and Page are concerned about the higher level of Eagle activity in more deprived neighbourhoods. ‘‘People living in poorer areas are probably more likely not to have double glazing, not to have air conditioning so have windows open if it’s hot, all of that kind of thing – so they’ve got greater vulnerability to noise when they are exposed to it,’’ Welch says.

For Page, the concerns run even deeper: ‘‘Given you’ve got a significant population density in there who are already adversely health-affected in terms of socio-economic factors, there’s an argument to be weighted against [the benefits] of, is this really what you should be doing? Because you’ve just added a whole bunch of other stress elements in there that are likely to result in poor health outcomes for a group that’s already got poor health outcomes.’’

Complaints about the Eagle helicopter are common, but they tend to be low-level grumblings among workmates, friends and on social media. Manurewa ward councillor Angela Dalton, who has lived in the area most of her life, takes comfort in hearing the Eagle overhead. ‘‘I lived alone in Weymouth and every time I heard Eagle I felt safe.’’ Operations requiring the helicopter to hover in place at length were ‘‘quite disruptive’’, she says. ‘‘But what can you do? You’ve got to really trust that they’re using their best judgement on something like that.’’

O¯ tara ward councillor Alf Filipaina, a former police officer, has a theory about who is complaining about the helicopter – and it’s not people in his constituency. ‘‘The people that end up complaining the most are the ones in the affluent areas who don’t want to have any bloody noise when they sleep. They’ll say, ‘Oh, they disturbed my sleep’ – well, maybe it’s because they were trying to catch people to make sure you were sleeping safely.’’

In the year to September, police received 227 complaints about the Eagle, of which 85 were from one complainant and 38 were from another. In his written response, police district operations manager Vaughn Graham said police ‘‘frequently’’ receive positive feedback about the helicopter.

‘‘There is some noise generated while attending incidents which we acknowledge may cause some inconvenience to residents, particularly at nighttime,’’ Graham said. ‘‘Where possible we take extra steps to minimise this inconvenience by flying neighbourly, where Eagle flies above the minimum height while moving between areas.’’

Auckland may be used to the sound of the Eagle, but what happens when you place it into a new community? In early 2020, police got permission to trial use of the Eagle in Christchurch, sending one of the three helicopters south for five weeks. There, it found a fresh, and largely unreceptive, audience. RNZ reported that four weeks into the trial, there were nearly 40 official noise complaints laid, while city councillors reported fielding further, informal complaints from disgruntled residents.

The dataset for Christchurch is smaller, but features similar patterns to Auckland: a focus on generally low-deprivation neighbourhoods (Aranui, Bexley, Phillipstown, Linwood, Edgeware), though more well-heeled suburbs like Bryndwr and Waimairi Beach are not immune.

A hearts and minds campaign, which included delivering the ball at the start of a Crusaders match, failed to change public perception. At the end of the five weeks, the helicopter had attended 346 incidents, resulting in 210 arrests – but the trial did not become permanent.

Wellington also got a taste of the Eagle helicopter in early March, when it was dispatched to monitor the end days of the anti-mandate protests in the capital’s parliamentary precinct. Here, it had a specific purpose and so the pattern is very different from Auckland and Christchurch.

Broad use and acceptance of aerial surveillance should not make the Eagle helicopter immune to criticism or change, Page says.

He believes alternative technologies could fulfil some of the Eagle’s duties. ‘‘The surveillance side of it... I would have thought modern drones could do that just as effectively and with minimal noise generation. And, when necessary, a helicopter comes in when you actually do need eyes and direct interaction.’’

Is drone technology up to the task, though? Central Otago-based company Landpro is one of several aerial surveying companies in New Zealand to introduce drones to its fleet. General manager and chief executive Jason Wills-Harvey says drones and other unmanned aerial vehicles (UAVs) are increasingly stable, can stay up longer than they used to, and are now capable of carrying multiple

sensing instruments.

Wills-Harvey is not convinced, however, that drones could replace much of the work of a police helicopter. ‘‘We’re sensing. But what we’re not doing is pursuing. You are limited to an artificial view of the world... As humans, we have a bit of an innate sense of what’s moving, what’s tracking… [With the drone camera] you miss some of those cues and those nuances.’’ He would never say never, though. ‘‘It’s definitely a ‘watch this space’ thing.’’

Helicopter crash inspector Tom McCready doesn’t think the regulatory framework exists yet to operate drones for police purposes. ‘‘In helicopters and aeroplanes, we have all sorts of inspection criteria... But a lot of those drones don’t.’’ That’s fine, he says, ‘‘until one flies apart over Auckland city and blades are coming through your house’’.

Elsewhere, though, drones are being used to complement and even replace some policing work being carried out by helicopters. In 2015, Devon and Cornwall Police became the first police force in the UK to use drones in this way, monitoring public protests and large music, sporting and community events; and for missing person searches.

The drone team’s Sergeant Chris Linzey says the advantages include lower cost, lower noise impact, lower risk,

and lower environmental impact. ‘‘Also, although drones have a limited flight time, as they are in close proximity to the ground crew, they can be quickly landed, have their batteries replaced, and be back in the air within just a few minutes.’’

New Zealand police have, in fact, used drones – though not as a replacement for the Eagle. Most policing districts have a handful of small quad-copter drones, and a 2020 ‘‘proof of concept’’ report revealed that 121 drone flights were made over six months, mostly to survey and photograph car crashes, arsons and other crimes.

The report concluded that for now, drones and other remote piloted aircraft systems (RPAS) were ‘‘not appropriate … for following high speed vehicles or tracking vehicle movements across multiple suburbs’’ although, ‘‘in the medium term it is possible that larger fixed-wing RPAS may be able to undertake some of the tasks currently performed by Eagle, such as fleeing driver tracking’’.

That was two years ago. When the Star-Times requested further information about any work to expand drone use, police provided this brief response: ‘‘While police continues to explore the use of RPAS and the benefits this technology can bring to police, nothing that would specifically replace the tasks currently being carried out by the Air Support Unit is being considered at this time.’’

NEWS

en-nz

2022-11-27T08:00:00.0000000Z

2022-11-27T08:00:00.0000000Z

https://fairfaxmedia.pressreader.com/article/281883007352248

Stuff Limited