The SS United States is in the process of being towed to its final resting place, on the sea floor near florida, to be a scuba-diving reef. She is the largest ocean liner to be entirely constructed in the United States and was the fastest ocean liner to cross the Atlantic Ocean in either direction, 36 knots or 41 mph average speed. She won the Blue Riband for this on her first voyage, in 1952, and retained that title till today. There was a faster crossing in June, 1990 by the Hoverspeed Great Britain, 36.6 knots, 42.1 mph average speed, but the Hoverspeed was a 76 meter channel catamaran, not an ocean liner.

The SS United States was half-paid for by the US government. Its purpose was fast passenger transport across the Atlantic. The government contributed because it might be used as a troop ship if needed in times of war. In terms of speed, she handily beat the luxurious British liners, Queen Elizabeth and Queen Ann, but the compromises for speed and military use made the SS United States unsuited for use as a luxury cruise ship.

Designed by William Francis Gibbs, one of the greatest ship designers, the high speed was achieved, in part, by making the ship very light. He used aluminum for the entire superstructure, the stuff above water level, making it the largest aluminum construction when built, 1951. Though larger than the Titanic, the United States is thinner and more pointy. Much lighter than the Queen Elizabeth or Queen Ann, she could go as fast backward as the Titanic could forward. The hull is doubled, with fuel stored between the layers as a protection from collisions and canon; the interior is highly compartmentalized too, to make her fairly unsinkable. This was confirmed when she survived a sea collision shortly after launch. Making the ship light on the top made the SS United States stable in wind and rough seas despite its narrow shape. There were two engine sections, divided into four engine rooms, done to increase the chances that the engines would survive an explosion or torpedo attack.

The interior design was American modern, and fire-proof, with few weighty decorations. Furnishings were fiberglass, steel or aluminum, for the most part, see picture below. The red, white, and blue stacks added to the American look. Both are used (recall that there are two engine rooms), and both have aluminum wings. These shield the deck from any sparks that might come out the stacks.

In the end, it was the crossing speed not the comfort level that doomed the SS United States. Even at a top speed of 44.1 mph, crossing the Atlantic took 3+ days. That could not compete with jet planes that travelled at 500 mph. I’ve argued that long range, “high speed” passenger trains make little sense for the same reason. Even at 100+ mph, few Americans will be willing to spend 36 hours traveling from Chicago to Seattle. Fast boats are useful, I think, but only in smaller size foreshorten trips, similar to the Hoverspeed.

Also helping it reach the speeds it did, the SS United States benefitted from innovations in the engines and in the propellers. There were four engines, in two engine sections. These were modern, light weight, compact, steam turbines running at high pressures and temperatures: 975°F and 925 psi. Each turbine delivered 60,000 shaft hp to a variable-speed, geared shaft. The inboard propellers had 5 blades and the outboard (end of ship) had four. This difference in blade number was a secret, design innovation that allowed faster speed, without vibration and cavitation. The 5 blade propeller shown on display at left, accelerated the water, while the 4 blade accelerated it faster. At the time, this was secret technology. We now have some better propellers, though no faster ocean liners. The Hoverspeed uses water jet for propulsion, by the way.

On its way to the bottom of the sea, the ship will first stop at MARS. That is not the planet Mars, but at an engineering firm, “Modern American Recycling Services” in Mobile Alabama, on The Gulf of X. There the MARS folks will prepare the ship to sink in an even way, where its supposed to; a way that works for scuba divers.

Robert Buxbaum, February 28, 2025. My sense is there is still room for steam power. I also think the US government should return to investing in US ship-building, especially for double-use, military and commercial, like this one. A new favorite phrase, from Ovid, Metamorphosis: “Omnia mutantur, nihil interit”. Everything changes, but nothing passes away. RIP, old friend.