The world's busiest airport just told the TSA to shape up or be replaced by private security

Atlanta's Hartsfield-Jackson International Airport, the world's busiest, has issued a warning to the US Transportation Safety Administration to get its act together or be replaced.

According to a letter from Hartsfield-Jackson general manager Miguel Southwell to TSA Administrator Peter Neffenger, the airport's security screening checkpoints are woefully understaffed with no sign of significant improvement in sight.

The letter, obtained from a source by Aaron Diamant of Atlanta's WSB-TV, was dated February 12. The TSA confirmed to Business Insider that it has received the letter and is evaluating it.

In the letter, Southwell says the chronic staffing shortages are leading to wait times of over half an hour at the TSA checkpoints. If things don't change, the airport will bring in private security personnel under the TSA's Screening Partnership Program, he warns.

"Several times throughout the day from May to October 2015, wait times (at TSA checkpoints) exceeding 35 minutes were not uncommon," Southwell wrote. "This is unacceptable as reflected in the customer service surveys of our hub carrier Delta Air Lines."

"This morning as I write this letter, wait times up to 52 minutes were experienced between 6:00 am and 6:30 am," he added.

'Dreading' 2016

According to Southwell's letter, the TSA's Atlanta Airport team did manage to get a 7.5% staffing increase last year, but that proved to be "late and inadequate." This is because Hartsfield-Jackson, the world's business airport with more than 96 million passengers in 2014, saw traffic increase 10% over that same period.

Further, Southwell claims that traffic jumped another 14% in the first quarter of this fiscal year which has it "dreading the outcome of 2016."

With no sign of additional staffing on the way from the TSA, airport management has initiated programs to promote expedited security programs like TSA Pre-Check or Global Entry and the adoption of new technology in the screening process. However, Southwell doesn't believe this will be enough to alleviate the airport's checkpoint problems.

"Even with all of our efforts, however, as the airport's experience demonstrates, things appear to be only getting worse," Southwell added.

"We recognize that the issues raised in the letter are a concern, not just in Atlanta, which is fueled primarily by the rapid growth in travel volume combined with a renewed focus on our security mission," Mike England, a spokesman for the TSA wrote in an e-mail to Business Insider. "Resolving these issues and achieving our common goal calls for a collaborative approach with our industry partners. While we are working on better solutions, we believe the public will support our vital mission of ensuring safe air transportation."

We have reached out to Hartsfield-Jackson Atlanta International Airport for comment and will update this post when we hear back.

Click here to read the full letter on WSB-TV.com.