John Ericsson - Propeller Design

Propeller Design

He then improved the ship design with two screw-propellers moving in different directions (as opposed to earlier tests with this technology, which used a single screw). However, the Admiralty disapproved of the invention, which led to the fortunate contact with the encouraging American captain Robert Stockton who had Ericsson design a propeller steamer for him and invited him to bring his invention to the United States of America, as it would supposedly be more welcomed in that place. As a result, Ericsson moved to New York in 1839. Stockton's plan was for Ericsson to oversee the development of a new class of frigate with Stockton using his considerable political connections to grease the wheels. Finally, after the succession to the Presidency by John Tyler, funds were allocated for a new design. Unfortunately they only received funding for a 700-ton sloop instead of a frigate. The sloop eventually became USS Princeton, named after Stockton's hometown.

The ship took about three years to complete and was perhaps the most advanced warship of its time. In addition to twin screw propellers, it was originally designed to mount a 12-inch muzzle loading gun on a revolving pedestal. The gun had also been designed by Ericsson and used hoop construction to pre-tension the breech, adding to its strength and allowing safe use of a larger charge. Other innovations on the ship design included a collapsible funnel and an improved recoil system.

The relations between Ericsson and Stockton had grown tense over time and, approaching the completion of the ship, Stockton began working to force Ericsson out of the project. Stockton carefully avoided letting outsiders know that Ericsson was the primary inventor. Stockton attempted to claim as much credit for himself as possible, even designing a second 12 in (300 mm) gun to be mounted in Princeton. Unfortunately, not understanding the design of the first gun (originally named "The Orator", renamed "The Oregon" by Stockton), the second gun was fatally flawed.

When launched, Princeton was an enormous success. On October 20, 1843, she won a speed trial against the paddle steamer SS Great Western, until then considered the fastest steamer afloat. Unfortunately, during a firing demonstration of Stockton's gun, the breech ruptured, killing Secretary of State Abel P. Upshur and Secretary of the Navy Thomas Gilmer, as well as six others. Stockton attempted to deflect the blame onto Ericsson, with moderate success, despite the fact Ericsson's gun was sound and it was Stockton's gun that had failed. Stockton also refused to pay Ericsson, and by using his political connections, Stockton blocked the Navy from paying him. These actions led to Ericsson's later deep resentment toward the U.S. Navy.