Retired Air Force Major General William “Neil” McCasland went missing last month … and his wife thinks his disappearance may have been intentional.

In the newly-released 911 call from his February 27 disappearance — obtained by Law&Crime Network — Susan McCasland Wilkerson tells the dispatcher that she has “some indication that he planned not to be found.”

She said Neil changed his clothes, turned his phone off and left it behind … which she noted “seems kind of deliberate, because he’s always got his phone.”

Susan stressed that her husband had “never” done anything “even remotely” like this … but told the dispatcher he’d been “saying if his brain and body keep deteriorating, he doesn’t want to live like that.”

But she didn’t think he was being serious, adding in the heartbreaking audio … “It seemed to me that was just a ‘man, I hate how this is going’ kind of thing. Because I told him, ‘Yes you do. Yes you do.'”

During the call, Susan explained that she and Neil had been seeing a doctor for anxiety, short-term memory loss and lack of sleep.

In fact, it was while Susan was seeing that very doctor that Neil vanished. She told the dispatcher … “I left for a doctor’s appointment at about 11:10 AM and he was here at that time, at the house. And I got back from that at noon and he was gone.”

Susan believes her husband took off on foot, saying their cars and bikes were all in the garage. She said Neil has a smart watch … but didn’t know if he was wearing it when he left.

At the time, Susan checked Neil’s gun safe to see if he brought any with him when he vanished … but couldn’t tell if anything was missing because he has “quite a number of pistols and rifles.”