Defense Department officials said those numbers aren’t tracked making it difficult to determine how widespread the problem might be.
A Tinker spokesman said McClelland-Hall’s was the second child pornography case at the base since 2009.
A spokesman at Altus Air Force Base reported no child pornography cases for at least the past five years.
Despite repeated requests, Fort Sill, the state’s largest Army installation, did not provide a response before publication.
McClelland-Hall enlisted in 2009 and served as a specialist with the 72nd Security Forces Squadron based at Tinker. His court-martial took place over two days in a small courtroom on the Oklahoma air base.
McClelland-Hall’s room- mate described how he found the pornographic titles after McClelland-Hall asked for help fixing his computer while both were stationed at Eskan Village Air Base in Riyadh, Saudi Arabia.
Military investigators testified how when confronted the clearly embarrassed airman became teary-eyed and emotional, and how McClelland-Hall willingly demonstrated how he had used his computer to search for, download and briefly view several child pornography videos.
Investigators said he told them he’d watched them about 10 times for no more than 10 seconds.
From Saudi Arabia, the computer made its way to Tinker, where an agent with the Air Force Office of Special Investigations selected and sent 27 images and videos to the Defense Criminal Forensics Lab for analysis.
Videos not deleted
Military prosecutors argued that McClelland-Hall previewed some of the videos while they were being downloaded, but did not stop the download. They also said that other videos that were downloaded were kept in a file on the computer and not deleted.
His civilian defense attorneys argued that McClelland-Hall mistakenly and unintentionally downloaded the material.
When he saw what it was he sought to delete it, but didn’t know how, they said.
McClelland-Hall, who was dressed in his blue Air Force uniform with close-cropped blond hair, did not testify.
The Air Force reported 11 child pornography convictions so far this year and 16 in 2011. The numbers don’t include service members tried in civilian courts. Defense Department officials said those numbers aren’t tracked making it difficult to determine how widespread the problem might be. A Tinker spokesman said McClelland-Hall’s was the second child pornography case at the base since 2009.