Who can forget the images of that 69-year-old Kentucky doctor -- David Dao -- who was knocked out, then dragged off a United Airlines plane when he refused to give up his seat on the overbooked flight from Chicago O'Hare to Louisville, Kentucky? In one remarkable act of poor customer service, United Airlines proved that it could indeed happen to anyone.

Previous reports say that United Airlines reached a confidential settlement with Dao to the tune of $140 million for the injuries he suffered, including a broken nose, a concussion, and broken teeth.

Just when the news of this horrific incident was beginning to fade from our collective consciousness comes news that the (now-ex) Chicago Aviation Police officer James Long --  one of the officers who dragged Dr. Dao from the flight -- has filed a lawsuit against United Airlines, Chicago Aviation Commissioner Ginger Evans, and the City of Chicago.

According to news reports, James Long claims that the incident, which happened just over a year ago, on April 9, 2017, resulted in him being unfairly terminated from his job. According to Long's attorney, his client

"is seeking action because he feels he was doing his duty at the time Dr. Dao was escorted off the plane. He was not in the wrong. But if he did do something wrong it was because the City of Chicago failed to properly train him."

Unfortunately, it appears that this incident -- and all the bad press it brought United Airlines -- hasn't gone away yet.

Here's a video of the incident, though I know I'll never forget it.