CHICAGO (CBS) -- The "Ledge" at Willis Tower has a new rival for skyscraper thrills in Chicago. The Hancock Center has its own gravity-defying feature, "Tilt," which lets visitors lean out over the edge of its observation deck at a 30-degree angle.
For an extra $5, visitors to the Hancock's 94th floor – now dubbed 360 Chicago – can walk into a steel-framed box that gradually tilts eight people at a time to a 30-degree angle toward the ground – more than 1,000 feet up in the air.
John Peronto, a structural engineer on the Tilt, said the wind speed at that height was one of the most critical obstacles to overcome.
"As the Tilt system moves in and out, there are three piston-like devices that push the actual steel frame outside the building about 50 inches, give or take, which creates the rotation of 30 degrees for the occupant," he said.
Hancock's New 'Tilt' Leans Visitors 1,000 Feet Above The Ground
The Ledge at the Willis Tower doesn't lean out like Tilt, but the glass boxes give visitors the illusion of standing on air, since even the floors are transparent.
Peronto assured acrophobic visitors there's no danger the Tilt box will lean out any further than designed.
"The system itself can't go beyond 30 degrees. There's hard stops embedded in the system," he said.
Ironically, Peronto's got his own fear of heights, so he won't be riding it much.
"I have been on it about a half dozen times. I think that's enough for me," he said.
Ald. Bob Fioretti (2nd) and Ald. Brendan Reilly (42nd) were on hand for Thursday's ribbon cutting for the Tilt.
Reilly had some joking remarks about their presence 94 floors up.
"We haven't let the mayor near that today, have we? Because two of his headaches could fall out the window," he said.
Reilly and Fioretti are two of Emanuel's more vocal critics on the City Council.
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