James Corley: Great article, but one MAJOR factual error. Yes, these carriers were erroneously called "27 Charlies" by the sailors - the angled deck was a SCB-125 design feature.
These ships, however, were NOT called 27C because of their displacement; that was a std disp of 33,000 tons. The 27 Charlie comes from their Ship Construction Bureau number (SCB-27) with the 27C being the third overall design in the sequence but only the second built. The contemporary CVS design was a SCB-27A update. The SCB-27B was never used and is often erroneously used to describe the experimental angled deck installation on Antietam.
The SCB-27C update included modernizing the ship to the 27A baseline with the addition of steam, not hydraulic, catapults being the largest additional factor, but the beam was also increased for added stability and the #3 elevator was moved to the side of the deck. There were only 3 pure 27C conversions: Intrepid, Ticonderoga and Hancock. Lexington had a conversion begun as a 27C, but had the new SCB-125 conversion added during the process. The 125 was the program that added the enclosed bow and angled deck to the class.
Most of the 27As also got the 125 update, except Lake Champlain. but did not get the 27C conversion. Oriskany did get a modified 27C/125A when she was upgraded.