BOSTON - USS Constitution "Old Ironsides" received a waterborne underwater hull cleaning and comprehensive inspection in Boston Harbor, April 6-7 in preparation for its upcoming May 19 dry-docking.
Constitution, the oldest commissioned ship in the U.S. Navy, last docked in 1995 and since then accumulated marine growth has fouled her hull. The Navy's Supervisor of Salvage and Diving (SUPSALV) administers the Navy's hull cleaning program and provides hull cleaning and inspections services through its government contractor, Seaward Marine Services.
Hull cleaning reduces operating fuel expenses, safeguards the environment via reduced greenhouse gas emissions, mitigates the spread of invasive species, and restores the hydrodynamics of the ship to improve its performance. Additionally, once a hull is cleaned, it affords divers the opportunity to assess the condition of the hull, hull coatings, and appendages for any damage prior to dry-docking.
The 217-year-old ship, launched in October 1797, is unique because its wooden hull is covered with thin copper sheets attached with copper nails. Historically, copper sheathing was used to inhibit marine growth and Constitution retains the sheathing for that purpose.