You are likely to see many references this week to the New York World Trade Center (WTC) Twin Towers, in the run-up to the 20th anniversary this Saturday of their tragic destruction – so here’s an interesting video clip showing the towers being built, that mentions a little-known Australian connection.
The clip, commissioned by the Port Authority of New York and New Jersey, was released in 1983, 10 years after the Twin Towers were completed.
Little did the filmmakers know the tragic fate that awaited the towers 18 years later, in the form of the ‘9/11’ terrorist attacks of 11 September 2001.
The video mentions how demolition of pre-existing buildings on the WTC site began way back in 1966, with 164 buildings torn down to make way for the giant towers and surrounding infrastructure.
It’s a refreshing change to see the Twin Towers going up, as opposed to falling down. Viewers are told early in the 15-minute clip that the WTC made use of “dramatic new engineering concepts”.
“The great height was made possible by the use of load-bearing walls,” says the narrator (1.34 into the clip).
“The exterior walls were designed to bear much of the weight of the towers.”
“The only interior support was a simple core of columns.”
The building has immense concrete floors. You can see one of them being smoothed down. (10.28 into clip)
200,000 tons of steel were used in construction – which is where the Aussie link comes in.
WTC Twin Towers construction underway
“In August 1968, actual steel construction began,” the narrator says.
“Kangaroo cranes, imported from Australia, were used for the first time in the United States.
“They would be the driving force behind the towers’ construction.”
The self-constructing tower crane (also known as the kangaroo crane or jumping crane) was invented by Eric Favelle in Australia in the early 1960s. The design allows the crane to boost its own height as the construction proceeds upwards.
Apart from being used to build the WTC, this Austrralian-designed crane has been used on many of the world’s tallest buildings, including the Petronas Towers in Kuala Lumpur and some of the tallest buildings in Dubai, like the wondrous Burj Khalifa.
Millions of words have been written about the WTC Twin Towers since the horrific attacks on them by Islamist terrorists, which killed over 2000 people. Reports have been drawn up and issued – and the usual crop of conspiracy theories, some truly bizarre, has sprung up alongside them.
Live television footage of the radically engineered, load-bearing walls of the Twin Towers being struck by two passenger aircraft was screened globally and seared into world consciousness.
Those with an engineering bent, wondering how a plane flying at high speed could have cut through the columns (steel box beams) of the exterior walls, may find the answer here or here. According to the world’s top engineers, it was all too possible.
Written by Peter Needham
