Some four or five years ago, following the death of the distinguished architect, Sir Philip Powell, a number of individuals had the idea of re-building an icon of mid-twentieth century architecture in which he had been very much involved – the Skylon. This extraordinarily graceful structure took centre stage at the 1951 Festival of Britain site on the South Bank of the River Thames in London. Its fine lines, futuristic appearance and gravity-defying qualities inspired a generation and heralded a new era in terms of structural design, yet it was constructed on a shoestring budget – a necessity at the time, as Britain’s economy struggled to recover from post-war austerity. How different from that other ‘temporary’ structural celebration, the Millennium Dome, built half a century later.
It was back in 1950 that Philip Powell and his practice partner, the American Hidalgo (‘Jacko’) Moya won the competition to design the Festival centrepiece, rather unimaginatively coined the ‘Vertical Feature’; the name ‘Skylon’ came later as a result of another competition. They were joined in this venture by the gifted structural engineer, Felix Samuely who ensured that the Skylon – a vertical ellipsoid with a maximum diameter if 13ft and a height of 250ft – was safely erected and remained stable. An almost ‘Wild West’ approach to the project is wonderfully described in Jacko Moya’s own words*, penned in 1951:
“Philip and I thought about balloons tethered to float over the exhibition, but it was difficult to find a way of keeping such objects stationed directly over the site in all wind conditions. We abandoned the idea when we found out that the world’s total supply of helium fell short of the volume that we would need to keep aloft a thing of the size that we had in mind. It seemed, therefore, that we had to design a tower built up from the ground.
“It was not too difficult to devise a system of three pylons and a cradle of cables to raise the body of the feature above the ground. The shape of the body came from a desire to make it clear that it was not a tower with the usual solid base, so we made it widest half way up and tapering to a point at the bottom and the top – a sort of cigar shape.
“As the structure seemed to be fairly simple we made some assumptions about weights and wind loads and worked out the stresses in the cables by the triangle-of-forces method which we had learned about in our first year lectures [remember, Philips and Moya were in their early twenties when they won this commission]. It seemed to be unnecessary to bother a structural engineer at this stage, so we submitted our design and waited.
“We were surprised to win the competition and immediately sought the assistance of Felix Samuely, who had been our structures tutor at the Architectural Association. Although he said that he thought it was ‘unusual’ to ask an engineer to work on a scheme which seemed to be designed already, he said that he would see what he could do, and agreed to be our engineer.
“After a short while he got rid of six secondary cables which we had thought were necessary to stabilise the three pylons, and he reduced by half the tendency of the main body to sway in the wind, a well-known wrecker of tall or thin structures. Samuely also introduced us to the idea of using the main supporting cables in compression as well as in tension so that they acted like long and thin struts. All this was done by tensioning the whole structure after it was assembled. Three hydraulic jacks, one under each pylon, were used to induce the tension.
“At the bottom of the cigar, the thin point where some of the greatest stresses occurred, Samuely had transformed it into something so simple and clean looking that it seemed quite remarkable that it could remain standing.”
Sadly, the Skylon had little more than a year with which to grace the South Bank skyline. Winston Churchill, who returned to power following the defeat of the Attlee government in the Autumn of 1951, deemed the whole Festival site a “socialist conspiracy” and promptly had it razed to the ground. The only surviving building from the time is the Royal Festival Hall, which has recently undergone a complete refurbishment. The destruction of the 1951 Festival site is now regarded as an act of politically inspired “architectural vandalism”.
Restoring the Skylon, which I mentioned at the beginning of this item, has recently been given a boost by architect and former RIBA president, Jack Pringle, a senior partner in the Pringle Brandon architectural practice. He is spearheading a campaign to see this iconic structure reinstated somewhere in Britain – including a possible site in its former home town.
Pringle has got together a team that includes engineering consultancy, Atkins, which has many structural engineering feats to its credit, including the world’s only seven-star hotel, the Burj al Arab in Dubai. His aim is to see the Skylon rebuilt for 2011 – a year before the start of the London Olympics and just in time to celebrate the 60th anniversary of the Festival of Britain.
Atkins design director, Hayden Nuttall says that everything about the Skylon seemed to defy gravity – it looked like it shouldn’t stand up, yet it did. In his view, it was an engineering “sleight of hand” – a magic trick using maths and physics. It was always designed to be a temporary structure (though, perhaps, not as temporary as things turned out); the reproduction, on the other hand, will probably have to stand for anything up to 100 years.
While rebuilding the Skylon would be a challenge, it is surely the perfect way of refocusing attention on the UK’s architectural and engineering tradition. With the sector facing a skills shortfall - made much worse by the wholesale redundancy of construction workers and professionals in the wake of economic downturn, there is an urgent need to inspire and not deter youngsters from careers in engineering and construction.
The London Festival of Architecture, which runs until July 20, is a great way of exploring this tradition. If you are in town this month, the British Film Institute on the South Bank will be showing a collection of films from its archive that examines the built environment of the South Bank and the legacy of the 1951 Festival of Britain.
* These accounts and much more can be found at the campaign’s web site: www.rebuildtheskylon.com
Les Hunt
Editor
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