Ask Phoebe: Freight trains rather than planes likely cause of noise in early hours

Freight traincan be loud and disruptive at times. Photo / NZPA

I live near Morningside train station and I am regularly awakened by planes and helicopters late at night (after 10pm) and in the early hours (1am-2am) during the week, not just the weekends. There doesn't seem to be any good reason for this activity. They're not emergency helicopters and I don't live anywhere near the airport. Are there any laws, regulations or restrictions on air traffic at night that will help me get a decent night's sleep? Chris Brown, Morningside.

The regularity of your nocturnal disturbances does indeed suggest that they are not emergency aircraft.

An experienced and highly qualified pilot of my acquaintance tells me that aircraft over the city fly under strict rules laid down by the Civil Aviation Authority.

These are visual flight rules (VFR) and instrument flight rules (IFR).

Those flying under VFR must be 300m above the ground. They fly mainly during daylight hours, except for the Westpac rescue and police helicopters, which may fly at night if emergencies so demand.

These aircraft in general use IFR, as obviously at night visibility is impaired.

Noise restrictions apply to these aircraft, as for any other.

What you are hearing is unlikely to be passenger aircraft, as they fly five to 10 times higher than helicopters are permitted to, and frequently descend over the Manukau Harbour.

However, as you live close to Morningside station, I'm wondering if what you are hearing are freight trains.

Jenni Austin, senior media adviser for KiwiRail, tells me that the times you mention coincide with usual freight services to and from Whangarei.

These services have been running at these times for many years.

I just used the relatively new Northern Busway for the first time, and found the buses most efficient and the drivers extremely courteous. It is quite a pleasure to ride the thing. However, much of the two-lane roadway - the northbound lane towards Albany - is excavated intermittently to some depth for what seem like serious structural repairs. Why should this be so early in its life? Richard Leary, North Shore.

Transpower is installing high-voltage electricity cables in the Northern Busway as part of its project to reinforce the power supply into Auckland and Northland.

Planning for this project has been under way for many years and involves installing underground high-voltage cables from Pakuranga to Albany and building two new substations at Wairau Rd and Hobson St.

The company took the opportunity to install ducts in the busway during its construction in preparation for the cable installation that is under way. The reason was to cause as little disruption as possible as it avoided having to trench along the entire busway.

The areas of excavation you have observed are around what are known as joint bays. The cables are pulled through the ducts to each joint bay where they are joined to provide a continuous circuit.

Transpower is working closely with Auckland Transport and the Transport Agency to ensure measures are in place to minimise the impact of its work for bus users.

To date, delays of around one minute in peak direction and two minutes non-peak have been experienced.

Transpower has been very pleased with the support and feedback it has received from the public for the project.

More information on the project is available from www.gridnewzealand.co.nz and on facebook.com/transpowernz