As Australia’s cities go up and our airports expand, airspace restrictions can prevent developers from realising their lofty ambitions. Is the sky the limit? We talked to airspace expert, Amin Hamzavian to find out.
“Airspace constraints can, in some cases, be the most limiting factor in a project’s viability,” says Hamzavian, managing director of aviation consultancy AvLaw.
Hamzavian (pictured) provides specialist advice to developers on airspace regulations and how they impact permissable building and crane heights. And he says even “tier one” developers can get caught out.
“We often see developers that have not carefully considered airspace restrictions when assessing a site’s feasibility, and sometimes ask for assistance after money has changed hands with landowners or, even worse, after construction has commenced,” he says.
Hamzavian has seen deals struck by developers that factor in council planning controls but not airspace. “In some cases, there is a very strict limit with absolutely no wriggle room,” he says.
In Melbourne, for example, residential skyscraper Australia 108 was trimmed, despite planning approval, after it infringed on airspace around Essendon Airport, located some 13 kilometres from the Southbank site.
And three floors were shaved off an apartment tower in the Melbourne suburb of Parkville to ensure emergency helicopter flights to the Royal Melbourne Hospital weren’t impeded – even though two-thirds of the apartments had already been sold off the plan and the development had council approval.
Australia operates under international standards that define two sets of “invisible surfaces” above the ground around an airport, Hamzavian explains. These surfaces protect an aircraft flying in and out of the airport when the pilot is flying by sight, and also when it is being guided by navigational instruments in conditions of poor visibility.
Any activity that infringes an airport’s protected airspace is called a controlled activity and requires approval before it can be carried out. Controlled activities include buildings that intrude into protected airspace as well as temporary structures like cranes. They can also include other activities that intrude into prescribed airspace through glare or even air turbulence from stacks or vents.
“It’s not just about building height. Cranes can penetrate airspace during construction – and this is often not considered until the project is well down the track.
“In 2016, ambulance helicopters were suspended from landing at Nepean Hospital due to cranes obstructing the airspace.
“There has been a significant shift in attention afforded to the importance of airspace issues in recent times as many projects are now are unable to progress beyond planning proposals without an aeronautical impact assessment being completed first. Building designs, especially outcomes of design competitions, crane types and heights are often unknown until later in the process, forcing assumptions based on worst-case scenarios.”
The challenge will only become more acute as cities densify, Hamzavian adds.
In Sydney, Kingsford Smith Airport is nearing capacity and is constrained by night-time curfews established to avoid disturbing residences as close as 0.6 kilometres from its runways. But as councils rezone former industrial areas to accommodate population growth, many new high-rise residential developments are being placed directly underneath the airport’s flightpath, he says.
The new Western Sydney Airport, which promises to keep runways 10.5 kilometres or more from the nearest residences and will not have a noise curfew, will still be at the heart of a region that will be home to an extra one million people by 2030.
And in Brisbane, outgoing Lord Mayor Graham Quirk has called on aviation authorities to relax restrictions that limit CBD developments to 274 metres. The mayor has said the city centre ceiling could stifle economic growth and wants to see building heights of up to 300 metres allowed.
While city planners and policy-makers grapple with the issue, Hamzavian says the “responsibility lies with the developer to be aware of the constraints”.
“We encourage our clients to get us involved, like they would any other consultant, as early as possible – even at feasibility stage before they start making deals and submitting planning proposals.”
In the past, development planning and aviation approvals were two separate processes, but Hamzavian says this is beginning to evolve.
“As the implications of construction activities on airspace management becomes clear, councils, town planners and developers need to work together.”