As engineers continued the slow work of setting the Hunley upright Thursday, scientists got their first good look at the Confederate sub's right flank.

It was sort of like Christmas morning for archaeologists.

"This is an amazing opportunity to see the sub from this standpoint," said Maria Jacobsen, senior archaeologist on the Hunley project. "It makes a large difference."

The Civil-War-era submarine has rested at a 45-degree angle since it was raised from the Atlantic Ocean in 2000, its starboard side lying against the 30 slings holding it in place.

This week, engineers have worked to tilt the sub upright a few millimeters at a time -- moving slowly to keep from possibly putting stress on the rusted iron hull.

The sub is now almost dead upright, and the rotation is supposed to conclude with the sub lowered into a holding track today.

By late Thursday afternoon, with the Hunley listing by less than 10 degrees, the folks inside the Warren Lasch Conservation Center got their first look at features on its right side, including a pie-sized hole in the bow and a protective fin that probably was designed to keep rope or other refuse from jamming the Hunley's dive planes.

While the port-side fin is covered in hardened sand and shell and slightly eroded by the current, the starboard fin is sleek and unblemished, and looked almost silver.

It is similar to the shape of a shark's dorsal fin.

"It was buried beneath the ship in the sand, and that protected it," Jacobsen said.

As interesting as that rare, untouched piece of the sub was, Jacobsen was most intrigued by the intense scouring on the starboard side of the bow. Years of seawater and sand rushing beneath the sub ate away at the hull, smoothing it and thinning it.

The hole exposed Thursday was exactly in the path of the scouring.

"There has been very serious scouring," Jacobsen said. "We could tell by the bow that there had been some, but you can tell from the starboard side that the scouring was intensive. This is going to tell us something about what happened to it."

Those answers will come after the rotation is complete, when conservators begin the arduous task of removing the concretion that coats most of the hull. Removing that hardened sand and shell is the last step before the Hunley undergoes a chemical bath to restore its metal hull.

Michael Drews, Clemson University's lab manager for the Lasch Center, said that engineers on Thursday corrected a minor problem that delayed the rotation slightly. Late Wednesday, scientists discovered that the sub's bow was lower than its stern. A few adjustments of the straps leveled the sub out, and the rotation continued.

Drews, like everyone else, marveled at how much smaller the sub looked when it was not lying on its flank.

"A bunch of people have said today that 'It looks like a real submarine now,' " Drews said. "For everyone, it will be like looking at something new."

Reach Brian Hicks at 937-5561 or follow him on Twitter at @BriHicks_PandC.