The massive longitudinal sectioned plan of Titanic that was used during the British Board of Trade’s inquiry into the tragedy is now on display at Titanic Belfast, the innovative museum which opened this year on the site of the former Harland and Wolff shipyard where Titanic was built. This is great news for Titanic enthusiasts because the plan was only displayed in public for the first time last year before being purchased by an anonymous private collector for a record £220,000 ($363,000) on May 31st, 2011, the 100th anniversary of Titanic’s launch. That collector has generously loaned it to the museum for permanent display.

Created by the Naval Architects Department of White Star Line, the plan was hand-drawn in India ink with red and blue chalk marking the places where the iceberg was thought to have torn through five of the ship’s watertight bulkheads on the night of April 14th, 1912. It is 33 feet long and almost five feet wide, drawn to a precise scale of 3/8ths of an inch to one foot, on a single piece of paper which was then affixed to a linen backing. It was captioned in great detail to make the complex design and usage of the boat clear to the members of the Board of Inquiry who used it throughout their investigation.

The plan hung from cables in the hearing room and was referred to constantly by eyewitnesses (among them the only two passengers called to testify: Sir Cosmo and Lady Duff-Gordon), experts (Ernest Shackleton testified on navigating icy waters and Guglielmo Marconi on wireless telegraphy), White Star officials, and commissioners during the 36 days of the inquiry.

You can see the full plan in greater detail in this BBC photo gallery. The red and blue chalk drawings added during the inquiry to mark the areas of impact are on the last two pictures.

Expert Una Reilly, who is co-founder of the Belfast Titanic Society, said the plan helped to dispel one of the enduring myths about the sinking.

“There has been for more than 100 years this theory that there was a 300 foot gash in Titanic,” she said.

“The actual total amount of damage caused by the iceberg was 12 square feet, which is the size of a normal room door. But it was the fact that it was in six different places.”

The Board of Trade inquiry ended on July 3rd, 1912, concluding that “excessive speed” had caused the sinking of Titanic. The plan was returned to the White Star Line and it remained in private hands, unseen by the public until its sale last year. All we know about the person who bought it is that he or she is Irish and a Titanic enthusiast who wants to share the awesomeness of this one-of-a-kind artifact with the public.

Before going on display, the plan spent five weeks being examined and tended to by paper conservator Sean Madden. He found it in excellent condition, even though it probably spent a few decades gathering dust in a White Star archive before some unknown person saved it from destruction in the 30s or 40s after the 1934 merger of Cunard and White Star. He also believes that a drawing of such detail and size could not have been produced in the ten days between the commissioning of the Board of Trade inquiry on April 22nd, 1912 and the first day of hearings on May 2nd, 1912. Madden thinks it was created in 1908 as a working drawing used for reference during Titanic’s construction in Belfast which is why White Star was able to produce it in time for the inquiry.

The titanic Titanic profile went on display in Titanic Belfast’s “Aftermath” gallery on Thursday, November 27th. There it will be seen by hundreds of thousands of people a year. There was concern before the museum opened this year in time for the 100th year anniversary of the sinking of Titanic that it would have a hard time recouping the £90 million ($144,000,000) investment in its construction. The Northern Ireland audit office estimated it would have to attract 290,000 visitors every year just to break even. It has attracted more than 600,000 visitors in just eight months.