The third of four offshore oil drilling rigs in the Tarzan class is set to leave LeTourneau’s Vicksburg shipyard for Texas Thursday.

“It’s smaller, but it’s more of a man, so to say it, than the Gorilla is,” general manager Mike Gray said Thursday as he led a tour of about 15 business and industrial leaders and elected officials through the rig on the bank of the Mississippi River south of the city.

The oil-exploration rig, named the Bob Keller, sits on three legs totaling 445 feet in length and can search for crude oil and natural gas at depths of 40,000 feet. The Bob Keller has a hookload, or pulling capacity, of 2 million pounds. This, in addition to engines carrying horsepower of 2,150, give it a more powerful, compact build than its larger counterparts, the 116-E class and the Gorilla class, Gray said.

Tarzan class rigs are designed for drilling in areas of less hostile weather conditions, such as the Gulf of Mexico, parts of the eastern Caribbean Sea, and the waters of the Middle East.

Up to 82 employees can be accommodated on the Bob Keller, each with amenities ranging from a movie theater-style satellite television viewing room to Internet connections in each employee’s living quarters.

After a series of continuous seesaw movements with its massive legs, the rig will be floated to Sabine Pass shipyard in Texas, owned by Rowan Companies Inc., LeTourneau’s parent company, for final refinements.

Nearly two years in the making, the third Tarzan class rig is part of a string of exploratory rig construction projects at LeTourneau, located south of the city on the Mississippi River.

“For something in a competitive business like this to be successful right here in Vicksburg is pretty phenomenal,” said Jimmy Heidel, executive director of the Vicksburg-Warren County Economic Development Foundation, who was on hand for the tour.

A fourth Tarzan class rig, which will be named the Hank Boswell, is under construction and has at least another year and a half before completion, Gray said.

LeTourneau Inc., is among Vicksburg’s largest employers. It built oil exploration rigs from its founding by Texas industrialist R.G. LeTourneau during World War II to the company’s shutdown in 1992. Two years later, however, the company resumed operation after it was bought by Houston-based Rowan Companies Inc., a major offshore drilling and land contractor.