The tallest structure of the world

If one asks for the tallest structure of the world, then one often gets as answer “Taipeh 101" or "CN Tower". This is however only correct, if one consider only free standing structures. If guyed towers are also considered then the 628 metre tall KVLY-TV-Mast in Fargo, North Dakota, which was built in 1963, is the highest structure of the world. However there was between 1974 and 1991 in the proximity of the Polish town Gabin approximately 96 kilometres northwest of Warsaw a tower, which surpassed also this giant. It was the 646 metre tall radio mast of the Konstantynow long wave transmitter.

Konstantynow Radio Mast from far away (Source: http://en.wikipedia.org/wiki/Warsaw_radio_mast )

Radio Towers insulated against ground

In opposite to TV towers and masts used for mobile phone services, which are only carriers of transmitting antennas, the whole construction of Konstantynow Radio Mast served as transmitting antenna. This is very common at towers used for long and medium wave transmission. For this use in most cases a mast construction must be used, which is insulated against ground.

Such a construction is realized by mounting the mast on a huge insulator, the so-called basement insulator and by fastening the guys with insulators toward its construction. Frequently the guys are also divided by insulators, in order to prevent unwanted drain of transmitting power over them.

Of course radio masts insulated against ground with high voltage to ground when in use for transmission make some operational problems. So the used insulators must be able to withstand high forces and sometimes also very high electrical voltages. Cables for the current supply of electrical systems on a tower insulated against ground, like the flight safety lamps or a maintenance elevator, must be laid inside the wire of a coil, which is switched in parallel to the basement insulator and which forms with a capacitor also switched in parallel to the basement insulator a resonant circuit for the transmission frequency. For maintenance work the transmitter had to be switched off at least when maintenance staff enters or leaves the mast. Work on the mast, while transmitter is running, is in principle possible, if it does not take place in the proximity of insulators, because like in the case of a bird sitting on a power line there occur no larger voltage difference at different part of the bodies of the workers, which may cause harmful currents in their bodies.

Of course such a mast, which is, because of its height, a favourable target for lightning, requires also extensive lightning protection equipment. However a conventional lightning conductor attached to the mast construction would let the transmitting power flow uselessly into the ground. Therefore one always finds at radio masts, which are insulated against ground a spark gap close to the basement insulator. Its distance is so selected that during the maximum operating voltage no spark can occur. In the case of a thunderbolt an electrical discharge over the spark gap takes place, which results in a short circuit of transmitter exit.

This let an automatic device shut off briefly the transmitter and prevents so the formation of an electric arc, which can destroy the spark gap. After a short break the transmitter is put automatically back on the air.

Konstantynow Radio Mast

Konstantynow Radio Mast was built between 1972 and 1974 by the Polish company Mostostal in Zabrze as transmitting antenna for the new long wave transmitter of the Polish broadcasting company in the proximity of the village Konstantynow, which is part of Gabin municipality, at 52° 22' 14"N and 19° 48' 23" E. This location was selected, because it is situated on one hand very central in Poland, so the transmitter could serve easily the whole country and on the other hand this area in the proximity of the river Vistula has because of its high underground water level a good electric ground conductivity making it very favourable for long wave propagation. There are different designs of transmitting antennas for long wave transmitters, which are characterised by different heights of the used masts (at given transmission frequency) and their efficiency. A design, which is particularly effective, but especially for long wave transmission requiring a very tall mast, is a mast insulated against ground with a height of half wavelength of radiated frequency. Such an antenna was realized in Konstantynow. Because its transmission frequency was 227 kHz (after 1988 225 kHz), the corresponding length for half wave radiator is 660 metres for this frequency (speed of light/(2 * transmitter frequency)). However each technically realizable antenna has a certain diameter. It leads to the effect, that already an antenna, a bit shorter than half wave length has the same behaviour as a half wave radiator, whereby the exact value of this shortening is described in a complicate manner of the relation of antenna length and antenna diameter.

So a height of 646 metres was sufficient for Konstantynow Radio Mast.

The transmitter, which used Konstantynow Radio Mast as antenna, belonged with an output power of 2000 kilowatts to world’s most powerful transmitters. It caused the occurrence of voltages up to 120000 volts against ground at the basement of the mast, so the mast had to be mounted on three columns each consisting of two 2 metre high insulators arranged on top of each other.

Nearby-photograph of Konstantynow Radio Mast (Source: http://jerzyjedrzejkiewicz.webpark.pl/str01/gabin-rcn.html )

The mast itself was a 646.38 meters high lattice construction of steel tubes, which was anchored in 5 levels by 50 mm thick steel cables. It consisted of 86 elements each with a length of 7.5 meters. The tower had a cross section in form of an equilateral triangle with a side length of 4.8 meters throughout its whole height. The diameter of the tubes, which built the edge of the triangle had a diameter of 24.5 centimetres. The thickness of the wall of these tubes decreased as a function of the height they were used on the mast from 34 mm to 8 mm.

Inside the mast construction a self-driving elevator was installed for easier access to the flight safety lamps and other parts of the mast requiring maintenance. This elevator needed approximately 30 minutes for a trip from the ground to the top. The total weight of mast construction was 420 tons, the weight of guys and insulators were 80 tons.

Konstantynow Radio Mast short before completion (Source: http://jerzyjedrzejkiewicz.webpark.pl/str01/gabin-rcn.html )

Seizes of constructive elements.

A – Longitudinal section of single section

B – Outside of single section

C – Cross section

D – Longitudinal section of mast basement

E – Longitudinal section of upmost section

Seize values for mast basement and upmost section are partly estimated values

The long wave transmitter Konstantynow was at day- and night time easily receivable in Poland and the surrounding countries. At night time, when long wave transmitters have a large range because ionospheric reflections of long wave occur, this transmitter could frequently heard also in Africa, Asia, America and even in Australia.

Collapse of Konstantynow Radio Mast

In summer 1991 the guys of Konstantynow Radio Mast were exchanged. When on August 8^th,1991 the last one of the three ropes of the highest guy level should be exchanged, some mistakes were done at this delicate work, which lead to the collapse of the construction. Because all workers had left the mast before, there were fortunately no injuries to persons. Some rumours occurred afterwards, that the collapse was also a result of sabotage. Nevertheless there are no strong proofs for this.

Debris of collapsed Konstantynow Radio Mast (Source: http://jerzyjedrzejkiewicz.webpark.pl/str01/gabin-rcn.html )

After the collapse of Konstantynow Radio Mast Raszyn transmitter took the task of Konstantynow transmitter. Raszyn transmitter, which went in service in 1949, uses as transmission antenna a 335 metre tall guyed lattice steel mast, which is insulated against ground and which belonged at time of completion to world’s tallest radio masts. In 1974 Konstantynow transmitter took its function, but Raszyn transmitter was still used as backup transmitter.

After 1978 Raszyn transmitter was used for transmitting a second program of the Polish Broadcasting company in the long wave range.

Because Raszyn transmitter cannot transmit for technical reasons on two long wave frequencies simultaneously, the transmision of the second program of the Polish Broadcasting company in the longwave range had to be discontinued after the collapse of Konstantynow Radio Mast

Of course the Polish Broadcasting Company did not want to give up Konstantynow transmitter and soon planned the reconstruction of the collapsed mast, if possibility with the original height. After long discussions, the company Mostostal got in 1995 the order for its reconstruction and it was already started with the refurbishment of the basements of the old mast, which should be also used for the new one. However it came to violent protests by the local population, who feared their health in danger by the powerful transmitter. Although none of the reports, which one gave in order, could prove without any doubts that the transmitter would be a health danger for the population and although the Polish Broadcasting Company offered as compromise to reduce transmission power from 2000 kW to 75 kW, protests continued.

At the end the project of rebuilding Konstantynow Radio Mast had to be cancelled and a new site for the transmitter hat to be found.

This was found on a former military area near Solec Kujawski. Because this location is situated far away from settlements, no protests from local population were expected. In 1998 one started with its construction and on September 4^th, 1999 its inauguration took place.

The new facility in Solec Kujawski uses as transmitting antenna a directional antenna, consisting of a 330 meters tall and a 289 meters tall guyed lattice steel mast. Both masts are grounded and are fed over the guy wires with the transmitting power which should be radiated.

Since inauguration of Solec Kujawski transmitter Raszyn transmitter is again used for transmitting a second programme of the Polish Broadcasting Company in the long wave range.

New long wave transmitter Solec Kujawski (Source: http://jerzyjedrzejkiewicz.webpark.pl/str01/gabin-rcn_02.html )

Although there are no broadcasting activities in Konstantynow nowadays, there are, except of the mast and the radio frequency powerline running from it to the transmitter building, still nearly all structures standing on the site. Even the concrete plate, on which once the tallest mast of the world stood and the basements, at which its guys were fixed, are still existing.

Aerial photograph of the site, where once the 646 metre tall radio mast of Gabin stood (Source: http://212.244.179.188/website/Orto/viewer.htm ).Above the letter „i“ of the word „Gabin“, one can see a round plate of concrete. This was once the basement of the tallest structure of the world!

The tallest structures of the world and in Europe today

Since 1991 the KVLY TV-mast in Fargo, North Dakota is with a height of 628 meters again the highest construction of the world. It will be presumably surrounded in 2008 by Burj Dubai, a skyscraper under construction in Dubai, which will presumably be 705 meters tall (the accurate value of the planned height of Burj Dubais is kept secret). The highest structure in Europe outside the GUS states is the 412 meters high long wave radio mast in Hellissandur, Iceland, which was built in 1963 and which is as the former Konstantynow Radio Mast insulated against ground. In the European Union the 385 metre tall FM- and TV- transmission mast in Donington on Bain in Lincolnshire, UK, which was built in 1965, is the tallest construction. The tallest structure in Poland is since 1991 the 360 metre tall FM- and TV-mast Olsztyn-Pieczewo, which was built in 1978. At least the European records will probably be not broken in nearby future…

FM- and TV-Mast Olsztyn-Pieczewo ( Source: http://en.wikipedia.org/wiki/FM-_and_TV-mast_Olsztyn-Pieczewo )

Source

http://www.zb.eco.pl/gb/19/gabin.htm

http://de.structurae.de/structures/data/index.cfm?id=s0000672

http://jerzyjedrzejkiewicz.webpark.pl/str01/gabin-rcn.html

http://jerzyjedrzejkiewicz.webpark.pl/str01/galerie/rcn/index_05.html

Please mail corrections and further information to Harald_der_Grosse@gmx.de