Like their lattice boom counterparts the cranes have a versatile crawler base making them robust and manoeuvrable on construction sites, yet unlike their counterparts the telecrawlers need no space or time on site to build the boom. "We have seen a tremendous uptick in demand for these machines over the last 12-18 months," says CEO of New York based dealer Empire Crane, Luke Lonergan. "Once customers take them they don’t realise how they got along without them. They can do foundation work in the morning and hook work in the afternoon," adds company president Paul Lonergan. The brothers founded the company together in January 2002 and today carry between 12 and 15 Tadano Mantis telecrawler machines at any time, ranging from 30t to 100t. The company is traditionally a sales oriented crane firm but for telecrawlers it made an exception. "We have invested a lot in rental and we convert a large number of rentals into sales," says Paul Lonergan.

Crane supply companies in other markets also report increased interest. AGD Equipment Limited in the UK stocks Marchetti 25t and 70t telecrawlers along with 30t and 50t IHI machines and a range of 3t to 9t Japanese made mini-cranes. "We have seen this market increase rapidly since we introduced the first 30 tons capacity machines into the UK in 1996," says managing director Robert Law. "In my view a telescopic crawler is mainly competing with a lattice boom crawler. It is quicker to erect and easier to transport and you don’t need as much space on site to string the boom together and erect it," he says, pointing to a job at the UK’s Reading train station where the 25t Marchetti Sherpina CW 25.35, was the only option for the contractor. The crane can retract to have a base width of just 2.5m. "It had to drive along the platform and lift in steelwork for a new canopy. "There was nothing else that could have done the job," says Law.

On the downside Law, and other suppliers, acknowledge that the capacity for a telecrawler is up to 25% less than that of a lattice boom of the same class thanks to the heavier boom, and capacity reduces accordingly along the radius. However this is not usually a deterrent for users who are primarily interested in the narrow footprint, fast mobilisation times and site flexibility.

"We really see telescopic crawler cranes as where the industry is going," says Dave Rees, sales manager at the UK’s NRC Plant Ltd. "The versatility and rapid set up times for these types of machines means that the cranes can roll straight off the low loader and into position, and within a matter of minutes they are ready to work.

"We have currently stock telescopic cranes in our rental fleet ranging from 5t to 70t, with a view to increasing the capacity range to 100t+ in the future," he says.

Against this backdrop then it is not surprising that manufacturers are investing in new machines. Both major manufacturers and smaller producers alike are targeting the segment. US manufacturer Link-Belt, which is owned by Japan’s Sumitomo Heavy Industries, is expected to add to its fleet in 2014. "We can go larger, we can go smaller and we intend to," says Link-Belt senior manager for telecrawlers Pat Collins. The firm currently has three successful telecrawlers in the US market ranging from 45USt to 100USt, the TCC 450, TCC 750 and the TCC 1100.

Development of these cranes began with the use of a Link-Belt rough terrain teleboom on a Hitachi Sumitomo SCX400 crawler base for use in Europe and the US. "We had been manufacturing the attachment for Sumitomo for several years. We watched that product develop and have some success. The reliability and quality was excellent so we started a 450USt over here in 2006. Right away customers liked it but also said that they would like a bigger one. By that point we were committed to the market and introduced the TCC 750," explains Collins. As the cranes gained acceptance and customers showed interest in larger cranes the 110USt TCC 1100 was launched in the uutumn of 2010. The 110USt machine is at the top end of telecrawler capacity allowing them to also compete in the general lift arena. Only Germany’s Liebherr has gone a long way above this at 220t with the LTR 1220, with a 60m boom, which carried out its first job in June 2013. Crane and heavy transport contractor Albert Regel GmbH added the machine to its stable of 35 machines and put it to work on construction of a building in Villingen-Schwenningen handling prefabricated concrete components. On the site the LTR 1220 hoisted loads of up to 21t and positioned components at a radius of up to 55m. For now Liebherr, which has 60t to 120t machines (as well as the enormous LTR 11200 designed for wind parks), says it is not working on any new models and notes that although it sees demand for the cranes sales are below that of all terrains in the same class.

However a key advantage that telecrawlers have over all terrains is that they don’t need outriggers to achieve the lift capacities. "A telecrawler is a time saver and productivity improver. Anywhere that there is repetitive repositioning you can save time by not needing to break it down and position outriggers as you do for rough terrain or all terrain cranes," says Tadano Mantis vice president for sales and customer support Ed Hisrich. "People are really starting to realise the benefits of the telecrawler concept, that being that it is a very quick machine to take from truck to work. Generally there is very little assembly, you don’t generally need extra people for moving around outrigger pads and making sure the machine is level, or assembly of booms as you do for lattice equipment."

Tadano Mantis has a wide range of machines and produces domestic and export models ranging from 27t to 100t. It is also working on new developments for 2014. Presently its newest is the 15010 which is an upgrade of the earlier 14010 and improved the machine from being 70USt to 70 metric t (77USt) for export. "The changes were relatively minor structurally because we have such robust development in the overall concept of the crane," says Hisrich. He says this robustness is vital and explains that designing the cranes as a standalone telecrawler is a key part of this. "We designed the crane completely as a crawler, to do pick and carry work, to work out of level as crawler cranes do. If you take an existing boom or upper from an all terrain and put it on a crawler under carriage you have designed your all terrain crane to work perfectly in level, but it is obviously quite easy for a crane on tracks to get out of level. As soon as you do that you induce loads into an all terrain boom that it was never intended to take," he says explaining that machines that do this need a lot of counterweight and sometimes outriggers to retain stability and achieve capacity.

Hisrich notes that the 2008 Tadano acquisition brought a lot of benefits to Mantis opening the cranes to a more global market through the Tadano sales and service network. "This means that we have come back from 2009 and 2010 which were poor in the crane world. It also enabled us to bring in some of the benefits that Tadano brought to the table as far as lean manufacturing and improving processes and overall quality of the machines," he says.

Dealers agree that the cranes have improved. "Mantis machines today are the best they have ever been and there is better support and quality control," agrees Paul Lonergan.

Tadano Mantis first designed its telecrawler in the late 1970s to build tanks but the market has become extremely diversified since then. Manufacturers say it is impossible to credit any single sector with the growth as telecrawlers serve such a wide variety of markets. "We don’t really look to one application or even a few — it is a really wide open from oil field service companies to a guy at the top of mountain on a dam site with really restricted access, or on site in a tight spot working stationary. These cranes are not just for hostile environments, they are really varied and run the whole gamut," says Link-Belt’s Collins.

Other firms point to more bridge building, plant work, services operations, conveyor builds and power line work as driving demand with airport, highways and railways maintenance also key.

"Airports like the machines, because they do not have unnecessary booms up during the night, so do chemical plants. Contractors like them, because they are ‘plug and play’. Operators like them because they are flexible and feel more sturdy than a truck crane," explains Hemmo Luijerink, telecrawler expert and adviser in China to Fuwa Heavy Industry Company. He says that the machines have slowly become more popular in China although they are competing with cheaper conventional truck cranes. Luijerink has advised Fuwa on the development of its FW 55T and successor the FW 65T, designing the first set of side-by-side winches to reduce the rear end working radius.

Despite the flexibility of the machines, foundation work remains a faithful customer in all markets. Tadano Mantis’ Canadian dealer Cropac Equipment recently rented the 77USt 15010 to contractor Icanda Corporation to drive 14in tubular piles for a bridge foundation in Quebec, Canada. The telecrawler worked with Bermingham Foundation Solutions L-15 vertical travel leads, a B-21 diesel hammer and an HHH-12 hydraulic spotter to install the piles in a cofferdam at 3:1 fore batters set by the spotter. Hisrich explains that the unique ability to quickly adjust both the telescopic boom and spotter length reduced the amount of excavation required because the boom could be retracted and spotter extended to achieve the required angle to drive the piles; then the boom could be extended and spotter raised and retracted to achieve the reverse batter (thus consuming less space) while loading piles into the lead system.

Back in Europe, Germany’s Sennebogen points to a recent local job involving foundations for its latest machine the 673 R HD crawler crane, a 70t class model with 36m telescopic boom, where contractor Himmel und Papesch (HuP) , headquartered in Hessen used the machines to erect steel solid-wall pylons during construction of a new 110 kV high voltage line along 35km in Lower- Saxony. The crane began with general lift for the removal and loading of the pylons before being used in combination with a Junttan hydraulic hammer for driving the foundations. This began by driving some existing foundations deeper into the ground with a 6t drop weight to create space for the new founding. This was followed by insertion of a 2m diameter steel ring, before the casing foundations up to 5m in length were driven vertically into the ground. Each mast took 2-3 days to install.

Like other manufacturers, Sennebogen says that it will continue to extend its product range and respond to the market. Italy’s Marchetti is also considering developing a new 90t machine.

"We started with a mid size machines to see what the reaction of the market would be. We have reached the expectations that we had in the beginning," says export manager Marcello Maestri. "Recently we shipped a unit to Singapore and we have reason to believe that we can continue to develop this market."

However Maestri is careful to point out that the firm is not trying to compete with the major telecrawler manufacturers on price and will focus on customised solutions for its customers. Recently it has adapted a number of its 70t Sherpa CW 70 machines for use in Africa and Finland. "They have gone from +45°C to -35°C. Of course we had to customise the machines for the extreme cold and the extreme heat but they are doing well."

Development of telecrawlers has been an evolution of the company’s all terrain models. "When we started with the telecrawler cranes we tried to use what we already had in our fleet. The boom from our Sherpa is the one used for the 70t all terrain crane. What we have added is outriggers which come from the truck cranes, to remain a niche so as not to go against the big players and to allow it to do other kinds of jobs," he says, noting that although the cranes combine uppers and lowers their performance is fully analysed and studied.

Whether the telecrawlers are taking market share from all terrains, rough terrains or lattice booms varies between dealers and markets. In reality they are taking a little from each. "There are still a lot of customers coming through that are seeing them for the first time — they haven’t gotten used to the idea of how it would fit their needs so that is what we work on every day," says Collins, who also credits the distributors for finding a place for telecrawlers in their fleets. "Telecrawlers take strong distributors because not everybody buys them at retail right out, so a strong dealer network is critical. If you don’t have the dollars this is an easy one for dealers not to put into their fleet. Ours stepped up and put them out there," he says.

Telecrawlers are more expensive than their all terrain and lattice boom counterparts, and dealers report that unlike many models these cranes have maintained strong rental rates despite the downturn. This is understood to be mainly due to the small number of manufacturers and distributors which ensured that when markets were flooded with lattice boom models the less available telecrawlers remained in demand and competition for these is growing keeping prices high. Despite this contractors are being seduced by their flexible ways and speedy set up thereby reducing cost overall. With several new models about to enter the market, and steady growth continuing to characterise the sector, telecrawlers are proving their worth and growing from the foundations that they have been building for decades.