The ITA Tower 

27 March 2023 tbs.pm/77534

The mast under construction

Work in progress on the new tower at Emley Moor – Britain’s first concrete television broadcasting aerial support

 

ITV 1972 cover

From ITV 1972, published by the Independent Television Authority

Rising to a height of some 1,100 ft [335m] above the rolling farming country of Emley, near Huddersfield in the West Riding of Yorkshire, stands the ITA’s new concrete transmitting tower.

This slender and graceful giant weighing more than 16,000 tons carries the ITA’s UHF and VHF aerials which bring Yorkshire Television to the homes of nearly six million people. It is the first television tower of its type in Great Britain, and the third largest in the world after those in East Berlin and Moscow. It is higher than London’s Post Office Tower by more than 400 ft. [122m]

The story of the new tower starts with the dramatic collapse of the old Emley Moor tubular steel mast in March 1969, the first time an ITA aerial mast had ever collapsed. As a result, viewers in the whole of the Yorkshire region were suddenly without the local ITV service. However, pictures were restored to 70% of them in the amazingly short time of four days using a temporary ‘zip-up’ mast brought from the ITA Station at Lichfield. Enormous credit is due to the stamina of the aerial erectors who worked virtually around the clock in appalling weather conditions in getting this temporary mast erected in such a short time.

A short-term solution to the problem of how to restore ITV to the whole of the region as quickly as possible, was found in the acquisition from Sweden of a special 680 ft [207m] mast which was ordered, imported, erected and brought into service in just four weeks from the time of the collapse of the old mast.

The tower

The new tower between two of the temporary masts

ITA engineers then immediately started considering the problem of a permanent replacement for the mast. Although a concrete tower of the type proposed was more expensive than conventional aerial support masts, it was decided to go ahead with the scheme, some of the points in favour being the relatively short time in which such a project could be completed, together with its pleasing and elegant design.

The design consultants appointed by the ITA were Ove Arup and Partners, and work on the construction was started in July 1969 by the main contractors, Tileman and Co. Ltd. Work progressed at such a pace that twelve months later the tower had soared to a height of almost 900 ft. [274m]

Using the temporary mast erected for BBC2, colour transmissions for ITV from Emley Moor were introduced as originally planned on 15 November 1969 – an achievement scarcely thought possible immediately after the catastrophe which occurred nine months previously. Just over twelve months later, in January 1971, the UHF aerials atop the tower were brought into service and in April 1971 the VHF service was transferred from the Swedish mast to the tower. Such an astonishing rate of progress after the disaster of March 1969 must constitute something of a record.

Even before work was started at the site, thorough tests were carried out on the new design. Foremost in these were investigations into the effects of thawing ice on concrete. These were conducted on simulated sections of the tower, the results showing that ice on concrete tends to melt from the outside inwards, whereas the reverse is true for ice on steel, and so the amount of ice falling from the tower in thaw conditions would be much less than for a steel structure. The tower’s resistance to buffeting by winds – a major point with such a tall, slim structure – was computer-calculated to be such that it would withstand the worst wind conditions that could be expected in 5,000 years.

The UHF aerials carrying ITV, BBC1 and BBC2 programmes are sheathed in a cylinder of glass-reinforced plastics, mounted on the top of a 180-ft [55m] steel lattice section at the top of the tower. The ITV VHF aerials are carried at the lower end of this section. Enclosed in a circular turret at 865 ft [234m], just below the aerial fixtures, is a room designed to carry the micro-wave link equipment used by Yorkshire Television on their outside broadcasts. A lift travels inside the tower to the 865-ft level, with intermediate maintenance levels spaced at every 150-ft [46m].

To mark the commissioning of the new tower, the ITA has produced a film, Tale of a Tower, telling the story of the new mast. Intended mainly for schools, colleges, and other groups interested in communications, the film deals with the construction of the tower, and looks at the day-to-day working of a transmitter and at the work of programme companies. The film runs for 25 minutes and includes impressive shots of the new tower taken from a helicopter.

 

You Say

2 responses to this article

Mike Pearson 27 March 2023 at 10:29 pm

BBC2 on UHF was restored from an Eagle tower from Manchester OBs in 2 days!

Harald Stelsen 30 March 2023 at 5:26 am

The height of the concrete tower is 274 m.

Atop that is a steel lattice mast which was originally 56 m tall, giving a total height of 330 m.

In 2019(?) Arquiva reduced the height of the steel lattice structure by 11 m to 45 m, giving a total height of 319 m.

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