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					Sky Tower
             Auckland Sky Tower

 Looking up at the Sky Tower / Sky Tower lit up at
               General information
               Communications, observation,
               mixed use, tourism
Location       Auckland City, New Zealand
Coordinates    174.762183°ECoordinates:
               36.848461°S 174.762183°E
Completed      1997
Opening        3 March 1997
Cost           US$50 million or NZ$76 million[1]
Antenna spire 328 m (1,076.1 ft)
Top floor      222 m (728.3 ft)
                Technical details
Floor area     5,500 m2 (59,202 sq ft)[1]
Elevators      4
             Design and construction
Owner           SKYCITY Entertainment Group
                Fletcher Construction[2]
Architect       Craig Craig Moller Ltd.[2]
Developer       Harrah's Entertainment[3]
                Beca Group[2]

The Sky Tower is an observation and telecommunications tower located on the corner of
Victoria and Federal Streets in the Auckland CBD, Auckland City, New Zealand. It is
328 metres (1,076 ft) tall, as measured from ground level to the top of the mast,[4] making
it the tallest free-standing structure in the Southern Hemisphere. Due to its shape and
height, especially when compared to the next tallest structures, it has become an iconic
structure in Auckland's skyline.


The upper sections of the Sky Tower

The tower is part of the SKYCITY Auckland casino complex, originally built for
Harrah's Entertainment.[3] The tower attracts an average of 1,450 visitors per day (over
500,000 per year).[5]

The upper portion of the tower contains two restaurants and a cafe — including New
Zealand's only revolving restaurant, located 190 m (623.2 ft.) from the ground, which
turns 360 degrees once every hour.[6] There is also a brasserie-style buffet located one
floor above the main observatory level. It has three observation decks at different heights,
each providing 360-degree views of the city. The main observation level at 186 m
(610.08 ft.) has 38 mm (1.5") thick glass sections of flooring giving a view straight to the
ground.[7] The top observation deck labeled 'Skydeck' sits just below the main antenna at
220 m (721.6 ft.) and gives views of up to 82 km (50.84 miles) in the distance.[8]

The tower also features the 'SkyJump', a 192-metre (629.76 ft.)[9] jump from the
observation deck, during which a jumper can reach up to 85 km/h (53 mph). The jump is
guide-cable-controlled to prevent jumpers from colliding with the tower in case of wind
gusts.[10] Climbs into the antenna mast portion (300 m/980 ft heights) are also possible for
tour groups,[9] as is a walk around the exterior.[11]

The tower is also used for telecommunications and broadcasting with the Auckland
Peering Exchange (APE) being located on Level 48.[12] The aerial at the top of the tower
hosts the largest FM combiner in the world[7] which combines with 58 wireless
microwave links located above the top restaurant to provide a number of services. These
include television, wireless internet, RT, and weather measurement services.[7]

The tower is Auckland's primary FM radio transmitter, and its second major terrestrial
television transmitter (after Waiatarua in the Waitakere Ranges to the west). A total of
twenty-three FM radio stations, two VHF analogue television channels, and three digital
terrestrial television multiplexes broadcast from the tower.[13][14] The analogue television
channels will switch off in the early hours of Sunday 1 December 2013 as part of New
Zealand's digital television transition.[15]

Glass flooring seen inside one of the observation decks

Sky Tower as part of the Auckland Skyline

Project history

Fletcher Construction was the contracted builder for the project while engineering firm
Beca Group provided the design management and coordination, structural, geotechnical,
civil, mechanical, electrical, plumbing, lighting and fire engineering services. Harrison
Grierson provided surveying services. It was designed by Craig Craig Moller architects[2]
and has received a New Zealand Institute of Architects National Award as well as
regional awards.[16][17][18]

Taking two and a half years of construction time, the tower was opened on 3 March 1997,
six months ahead of schedule.[19]

Project team

Project Architect: Les Dykstra[20][21]
Facts and figures

The tower is constructed of reinforced, high-performance concrete. Its 12-metre (39 ft)
diameter shaft (containing three lifts and an emergency stairwell) is supported on eight
'legs' based on 16 foundation piles drilled over 12 m (39 ft) deep into the local
sandstone.[17][18] The main shaft was built using climbing formwork.[18]

The upper levels were constructed from composite materials, structural steel, precast
concrete and reinforced concrete,[18] and the observation decks clad in aluminium with
blue/green reflective glass. A structural steel framework supports the upper mast
structure. During construction 15,000 cubic metres (20,000 cu yd) of concrete, 2,000
tonnes (2,200 short tons) of reinforcing steel and 660 tonnes (730 short tons) of structural
steel were used. The mast weighs over 170 tonnes (190 short tons).[18][22] It had to be
lifted into place using a crane attached to the structure, as it would have been too heavy
for a helicopter to lift. To then remove the crane, another crane had to be constructed
attached to the upper part of the Sky Tower structure, which dismantled the big crane,
and was in turn dismantled into pieces small enough to fit into the elevator.[18]


The tower is designed to withstand wind in excess of 200 km/h (120 mph) and resist
earthquakes with a 1,000 year return period. Analysis shows that an earthquake centered
40 kilometres (25 mi) away and reaching 7.0 on the Richter magnitude scale is expected
to leave the tower practically undamaged. Even an earthquake measured at a magnitude
of 8.0 (31.6 times more energy released than a 7.0 quake), and located only 20 km
(12 mi) away, is not expected to collapse the tower.[18] As an additional safeguard against
emergencies, fireproof rooms on the lower levels of the observation deck would provide
refuge in the unlikely event of a conflagration, while the stairwell itself is also fire-safety

The Sky Tower has so far been closed at least once for weather-related reasons, during a
storm in November 2006, when the structure started to sway noticeably in winds of up to
150 km/h (93 mph). The closure was noted as not having been strictly necessary except
for visitor comfort, as the tower has been designed to sway up to one metre (39 in)[23] in
high winds of up to 210 km/h (130 mph), which are expected to occur only once in 1,000
years on average.[18]

Sky Tower illuminated in Christmas colours. Various other lighting schemes and colours
are also used.

The Sky Tower features prominently on the Auckland skyline at night due to its extensive
illumination and SkyCity uses this lighting of the tower to promote various causes using a
number of colours or mix of colours. A few examples are:

      Blue = Auckland Blues Rugby franchise
      Pink = Breast Cancer Awareness Month
      Red & Green = 'Kidz First' Childrens Hospital/Christmas
      Red & Gold = Chinese New Year
      Blue & Green = Starship Children's Foundation
      Orange = Auckland Festival
      Green & Purple = The Auckland Cup
      Green = St. Patrick's Day
      Red = The America's Cup
      Green, Red and White = Rally New Zealand
      Gold = New Zealand Olympians at the XXIX Olympiad
      Blue & Red space = Matariki
      Blue, White & Red = Bastille Day
      No lighting (except aircraft warning lights) = Earth Hour

Energy efficient lighting

Over the week ending 29 May 2009 the previous metal halide floodlights, which had
been used since the Sky Tower's construction in 1997, were replaced with LED lights to
reduce energy usage. The project began in October 2007. The previous lights were
difficult to modify, repair or change colours due to the building's height.[24] The new
lighting system produces more lumens per watt and uses 66% less energy compared to
the previous floodlights, with a longer working life. They also produce less heat,
remaining cooler. The LEDs can produce millions of different colours and be controlled
from a laptop, compared to the previous method of manually installing filters to change
light colours. On this day a rainbow display was shown to the public at night, after the
LED lights were successfully trialled the night before.[25]

Energy conservation initiatives
During the winter months, electricity consumption in New Zealand increases
dramatically. As much of the power reserve in the country depends on the water level of
the hydro-lakes, various power-saving schemes are introduced to prevent blackouts.[26] In
an effort to promote power saving, SkyCity turned off the tower lighting in Winter 2008,
retaining only the flashing red aviation lights. SkyCity is also minimising façade flood
lighting across its complex. Simon Jamieson, General Manager SKYCITY Auckland
Hotels Group, said: "Like every New Zealander, we are concerned about the country's
electricity supply, and we believe it is our responsibility to make this move to assist with
the power saving request." [27] The tower was reilluminated on 4 August in support of
New Zealand athletes competing at the Beijing Olympics.[28]

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