Tallest Building, Largest Ship

Despite global economic doldrums, Kuwait is building a 3,284 foot tower-construct destined to make the 2,300 foot Burj Dubai feel like an also-ran. The new Mubarak towers will consist of three interlocking spiral towers with moveable aelerons on the trailing edges. The construction is meant to serve the practical purpose of making efficient use of real estate for housing purposes. As described, the building will almost contain self-contained cities within a city -- like an urban arcology.

Although the three-pronged design keeps the high-rise from swaying, it doesn’t counter the choppy winds that whip around the uppermost stories, which can cause damaging vibrations. So Kuhne is trying something never before done on a building: giving it vertical ailerons, the normally horizontal flaps on the trailing edge of aircraft wings that control rolling motion. The ailerons, which are only three to six feet wide, run the full length of each edge of the towers and mechanically adjust to redirect the changing winds around the structure and scatter the vortices, mitigating vibrations.

The Mubarak’s size is intended to accommodate Kuwait’s explosive population growth, with seven 30-story neighborhoods stacked atop one another, each with apartments, offices and hotels, and four-story “town squares” linking them. Even the height has a cultural significance, Kuhne says. “One thousand and one meters for [the classic Arabian fairy tale] One Thousand and One Nights. It’s the difference between bragging rights and telling a story.” _PopSci

In Florida, the world's largest ship -- The Oasis of the Seas -- is being constructed. Although not exactly a seastead, it is approaching the size of an actual "floating city." It will have room for 6300 passengers, and features an outdoor tree-filled park.

Royal Caribbean engineers widened the hull and split the box in half, erecting two six-story towers of cabins on either side, with enough space between them to fit the football-field-size park.

To maneuver this new giant, three 20-foot-tall propellers pull rather than push the boat through the water. The propellers are mounted on swiveling pods along with electric motors (powered by diesel generators in the ship) delivering the equivalent of 30,000 horsepower. This system is more efficient, because it eliminates the need for a long drive shaft, which typically creates drag under the ship. The propellers can rotate 360 degrees, so they also act as the steering system, allowing the captain to make adjustments in port of as small as one foot. _Popsci

The ship will feature a huge central atrium offering views of a central recreational area.

It is easy to conceive of a few small design changes that could turn the Oasis of the Seas into a full-fledged seastead, capable of sustaining a full-time living, working population at sea for extended periods of time. All that is lacking is the workable business model that would provide the income to replace expected passenger fees.