Editing USS Constitution (section)

===1995 reconstruction===
''Constitution'' entered dry dock in 1992 for an inspection and minor repair period that turned out to be her most comprehensive structural restoration and repair since she was launched in 1797. Multiple refittings over the 200 years of her career had removed most of her original construction components and design, as her mission changed from a fighting warship to a training ship and eventually to a receiving ship. In 1993, the Naval History & Heritage Command [[Naval History & Heritage Command#USS Constitution and NHHC Detachment Boston|Detachment Boston]] reviewed Humphreys' original plans and identified five main structural components that were required to prevent [[Hogging and sagging|hogging]] of the hull,<ref name="CSM7261994">{{Cite news | work = The Christian Science Monitor | date = 26 July 1994 | page = 12 | title = 'Old Ironsides' Gets a Major Overhaul |author = Nichols, Judy }}</ref> as ''Constitution'' had {{convert|13|in|abbr=on}} of hog at that point. Using a 1:16 scale model of the ship, they were able to determine that restoring the original components would result in a 10% increase in hull stiffness.<ref Name="PatrickOtten">{{cite web|last=Otten |first=Patrick |title=USS Constitution Rehabilitation and Restoration |publisher=Naval History & Heritage Command |date=March 1997 |url=http://www.history.navy.mil/constitution/restore.htm |access-date=25 March 2011 |archive-url=https://web.archive.org/web/20110509160909/http://www.history.navy.mil/constitution/restore.htm |archive-date=9 May 2011 }}</ref>

Three hundred scans were completed on her timbers using [[radiography]] to find any hidden problems otherwise undetectable from the outside—technology that was unavailable during previous reconstructions. The repair crew used sound-wave testing, aided by the United States Forest Service's Forest Products Laboratory, to determine the condition of the remaining timbers that might have been rotting from the inside.<ref name="CSM7261994" /> The {{convert|13|in|abbr=on}} of hog was removed from her keel by allowing the ship to settle naturally while in dry dock. The most difficult task was the procurement of timber in the quantity and sizes needed, as was the case during her 1920s restoration as well. The city of Charleston, South Carolina, donated live-oak trees that had been felled by [[Hurricane Hugo]] in 1989, and the [[International Paper Company]] donated live oak from its own property.<ref Name="AmericanForests">{{cite journal | last = Nickens | first = Eddie | title = Restoring Old Ironsides&nbsp;– frigate USS Constitution | journal = American Forests | date = November–December 1993}}</ref> The project continued to reconstruct her to 1812 specifications, even as she remained open to visitors who were allowed to observe the process and converse with workers.<ref name="CSM7261994" /> The $12&nbsp;million project was completed in 1995.<ref name="ChiTrib07-22-97">{{Cite news | work = Chicago Tribune | date = 22 July 1997 | page = 1 | title = As Time Briefly Stands Still, Old Ironsides Sails Solo Again on its 200th Birthday |first=Fox|last=Butterfield }}</ref>