The SS United States is shown at speed going over 38 knots during sea trials.
In May of 1952, with the SS United States more than 90% complete, initial sea trials were conducted. These trials proved without a doubt that the liner SS United States would capture the Blue Ribbon and complete the fastest transatlantic crossing in history. The ship was noticeably free of vibration.
In June of 1952, a second more rigorous set of sea trials were conducted on America's superliner. 1,700 invited guests, reporters, and crew were onboard to witness the trials. William Francis and his brother Frederic Gibbs were onboard, along with 150 United States Lines personnel who were guests. The trials were conducted by the shipbuilder as the SS United States had not yet been turned over to United States Lines. The SS United States raced up and down the Virginia Capes. The ship was put through the rigors of crash stops, full rudder tests, and stability tests. Mechanical tests were also performed. The ship even traveled in reverse at a phenomenal speed of 20 knots, nearing the top forward speed of the ill-fated Titanic. The ship is reported to have reached an astonishing top speed of 43 knots for a brief period of time, outpacing a speeding Navy Destroyer! The SS United States performed beautifully in gale force winds and moderately rough seas. Roll and vibration was minimal, and the ship remained very stable at high speed. The ship met or exceeded all performance specifications, and even exceeded the expectations of William Francis Gibbs himself.
The SS United States is shown here going 20 knots in reverse during sea trials.
I obtained the above diagram from William Tilley of the Independence Seaport Museum in Philadelphia. Special thanks to William for sending it. He used it as a slide in his lecture in Philadelphia on June 22, 2002. It is from John Kane's paper "The Speed of the SS United States," read before the Society of Naval Architects and Marine Engineers on November 3, 1977. John Kane was the Vice President of Newport News Shipbuilding and Drydock Company during that time.
In the diagram above, the left side depicts the stern and the right side depicts the bow of the SS United States. The above diagram illustrates the concept of "fine ends." The smooth hull design is evident in the lines of the diagram and allowed the SS United States to travel through the water faster than any other ship of her kind.
The SS United States was capable of traveling through the water at such a high rate of speed due to a number of factors. The first reason is hull design. The SS United States has very "fine ends" meaning a narrow and streamlined bow and stern which allow the ship to move through the water with the least amount of resistance possible. The SS United States has a smooth welded steel hull which cuts down on "skin friction." This contrasts with more traditional riveted plating which creates more friction as a ship moves through the water. "Fine ends" and a smooth steel hull allowed the SS United States to almost glide through the water producing very little wake. There are no bow waves producing the traditional V-shaped wake. Instead, the SS United States delivered a flat, boiling turbulence that disappeared about 1/4 of a mile aft of the ship.
In addition, the SS United States had a very high power to weight ratio. The ship's powerful engines produced up to 247,785 SHP, which was considerably more than the 158,000 SHP Britain's Queens were capable of delivering. The extensive use of aluminum helped to minimize weight, and the SS United States weighed approximately 53,300 tons, or roughly 30,000 tons less than the Queen Mary, which was of comparable size. America's superliner SS United States was clearly poised to capture the coveted Blue Ribbon from Brittain's Queen Mary on her maiden voyage.