Boeing South Carolina’s proposed land deal with Charleston airport officials is up in the air.

Four months after Charleston County Aviation Authority voted to sell 320 wooded acres across from Boeing’s North Charleston campus to the aerospace giant for $12.5 million, the Federal Aviation Administration is questioning the deal, authority attorney Arnold Goodstein said Tuesday.

“They are asking lots of questions,” he said during the panel’s board meeting.

The FAA is raising concerns over the price the Aviation Authority agreed to sell the land for and the land purchase’s effect on overall airport operations in the future, Authority Chairman Andy Savage said.

“The appraisal is just one concern,” Savage said. “They have other issues.”

Among them, he said, was the land deal’s possible “interference with airport operations.”

The deal cannot go forward without FAA approval, Savage said. If it’s not approved, it could land back in the hands of the Aviation Authority and Boeing, he added.

Boeing South Carolina spokeswoman Candy Eslinger declined to comment.

Goodstein and other airport officials along with representatives of Boeing met with FAA officials Monday in Washington to try to move the land purchase along.

Savage said Aviation Authority officials made it clear to the FAA that the authority, though it didn’t get the deal it wanted on the land purchase, stands behind Boeing in its pursuit of the property.

“Boeing is here to stay,” said Mount Pleasant Mayor Billy Swails, who also serves on the Aviation Authority. “It’s important for this to succeed.”

Goodstein said the authority would continue to press forward and try to answer the FAA’s questions.

“We will keep you posted,” he told board members.

The Aviation Authority voted in March to sell the Chicago-based aerospace giant land along International Boulevard for $12.5 million, splitting the difference between a set of second appraisals conducted by both parties. The Aviation Authority’s initial appraisal came in at $27.6 million, a number the FAA is looking at, Savage said.

Airport officials said the first appraisal valued the land as if it were ready for development. The costs of filling numerous wetlands and removing a radar site were not considered.

Boeing has not said what it intends to do with the property, but it doesn’t intend to bank it or sell it for another purpose.

The airplane manufacturer announced in April it will add at least 2,000 jobs by 2020 at its North Charleston campus, where more than 6,000 employees already assemble the 787 Dreamliner passenger jet.

Boeing also has expressed interest in buying the 265 acres it now occupies, as well as 488 acres near Dorchester Road and adjacent to Charleston Air Force Base.

Reach Warren L. Wise at 937-5524 or