Posts tagged with "Antennae":

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The view from this South Dakota TV Tower is as grand & dizzying as any Manhattan skyscraper

04-tower-vid While here in New York City, the antennas we cover tend to sit atop skyscrapers like the World Trade Center, for much of the American landscape, the tallest fixtures are spindle-thin television towers that keep watch over an agrarian landscape. But the view from atop those towers can be just as beautiful as the view from a $100 million Manhattan penthouse, as this drone video proves. A day on the job for project manager Kevin Schmidt involves scaling a 1,500 foot television tower to change a lightbulb. A vertigo-inducing video of the climb shot by Schmidt’s colleague, Todd Thorin, using a Quatrocopter drone sent pulses racing and went viral on YouTube—and for good reason: it's stunning. Shot for Thorin’s aerial photography and videography startup, Prairie Aerial, the footage shows Schmidt’s painstaking climb, rung by rung, as the ground becomes increasingly distant and the buildings mere pinpricks. The TV antenna in Salem, South Dakota is operated by KDLT-TV and has been inactive for some time, but a functioning light bulb is necessary to warn pilots to circumvent the sky-high mast. An employee of Sioux Falls Tower and Communications, the climber with nerves of steel has been screwing in light bulbs at dizzying heights for eight years on outposts in dozens of states through rain, shine, sleet, and snow. Even at wind speeds of 60mph, it’s business as usual. “Some of my friends can’t believe I do it,” Schmidt told USA Today. “They get scared on top of their house.”
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Kammetal Tops Off SOM’s One World Trade Center

Seven tons of glass and steel clad a structural stainless frame on the Western Hemisphere’s tallest building.

Brooklyn-based metal fabrication company Kammetal and DCM Erectors of New Jersey were selected to fabricate and install the crowning beacon atop the spire on 1 World Trade Center. The fabrication team executed SOM’s design for a dynamic and complex adornment to one of the country’s most anticipated buildings, along with the help of engineers at Buro Happold to ensure safety at 1,776 feet. To craft a 15-ton, 50-foot beacon that accounted for thermal expansion and movement, Kammetal modeled and drew their designs in SolidWorks. The company’s team laser cut 48 triangular 316 stainless steel panels with ¼-inch thickness in a nondirectional finish to clad DCM’s square tubular steel frame. “Before we started the project, we had the structural frame 3D scanned to generate a point cloud,” explained Sam Kusack, president at Kammetal. “Because the structure was so dynamic—it contains zero right angles or reference points—we had to verify the conditions.”
  • Fabricators Kammetal, DCM Erectors
  • Architects Skidmore Owings & Merrill
  • Location New York
  • Date of Completion May 2013
  • Material 316 stainless steel, stainless steel tubing, tempered laminated glazing, bolts, custom gaskets
  • Process SolidWorks, laser scanning, laser cutting, press brake forming, welding, machining, hand assembly
Once the angles were defined, multiple processes were employed to achieve the gentle curves of the cone. In order to ensure even bumping, or bending on a press break, the fabricators laser-scribed lines at every 1/8-inch along the panels’ interior. And to securely fasten each panel to the complex angles of the frame, Kammetal also devised a proprietary clip system that affixes each panel without obstruction. Clips that fell along certain angles could not be bent safely and had to be welded into place. To install tempered and laminated heat-soaked glass panels from Oldcastle, Kusack designed a proprietary vacuum panel lifting mechanism to adjust the panels without affecting the edges. “There’s a gap of just 3/8-inches, so it was the only way to handle the panels,” he told AN. The arm required a unique radius and capacity for strength to pick up each panel in a balanced manner and evenly align the gaps. Custom gaskets fabricated in London seal the glass from the elements. Kammetal also realized SOM’s original design for a rainscreen, which serves as a ventilation component. The beacon houses various mechanicals, including FAA lighting, so slots were laser cut to allow for air-cooling. To install the beacon, DCM Erectors fabricated a series of frames, supports, platforms, and transportation devices to safely place the beacon on top of the spire. “The owner of DCM invented a lot of gear and technology to realize this installation,” Kusack marveled. For example, a holding location was constructed at 1,700 feet to assemble the final interior and exterior components that all had to be raised an additional 70 feet so the apex could be lowered into place.
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One World Trade Center unseats Willis Tower as western hemisphere’s tallest building

Move over, Willis Tower. The Council on Tall Buildings and Urban Habitat (CTBUH) issued its official ruling Tuesday: New York’s One World Trade Center unseats the Chicago skyscraper as the tallest building in the Western Hemisphere. The new tower’s symbolic height of 1,776 feet was called into question when a design change suggested it might achieve that elevation only through the addition of a removable broadcast antenna. CTBUH counts only structural elements that are considered an integral part of the building’s aesthetic. It was designers Skidmore, Owings & Merrill’s assertion that 1 World Trade Center’s communications equipment represented a permanent architectural feature that persuaded CTBUH to affirm its height. The bottom point of the building was also in dispute. Without antennae, 1 World Trade Center is 1,368 feet tall — the height of the original World Trade Center tower destroyed in the 2001 terrorist attacks on Sept. 11. Chicago’s Willis Tower (also an SOM building), still commonly referred to as the Sears Tower, stands 1,451 feet tall — 1,729 feet tall with antennas. It was the tallest building in the world until 1996, when the Petronas Twin Towers in Kuala Lumpur, Malaysia, won CTBUH’s recognition.
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Childs vs. Durst: WTC’s Stripped Spire Stokes Controversy

The Durst Organization and the Port Authority have decided to abandon designs for what they once assured the public would be the tallest building in the Western Hemisphere, and architect David Childs of SOM is fighting back. By stripping away the sculptural finishes designed by SOM with artist Kenneth Snelson the developers and the Port may no longer qualify for the tallest title bestowed by the Council of Tall Buildings and Urban Habitat, the body that tallies and ranks building heights. In today's New York Times a spokesperson for the Council said that the galvanzized steel replacement would probably be interpreted as an antenna and not a spire and would not qualify as part of the building structure. Besides losing the title, the developers will also arguably be pulling one of the most significant works of art from the site. Douglas Durst told The Wall Street Journal that the spire should have been designed better as it will cost too much to maintain. "It's not the end of the world," he told the paper. To the Times he indicated the utilitarian replacement should work just fine: “I try not to get involved with the aesthetics. We’re here to discuss how it’s built and how it’s maintained.”