Some airports have those flat escalators (moving walkways?) and when you are nearing the end a loud voice warns you - something about getting to the end of the walkway.
I don't think it is for blind people, either, I think someone fell in or got caught up in the end of the thing and now all of us have to listen to that announcement play over and over and over.
Actually, the moving walkways had their start (and initial problems) in an aviation environment
From
http://todayinsci.com/Events/Technology/MovingSidewalks.htm:
When the moving sidewalk was first opened with the new terminal building at the city's new municipal airport, Love Field, in Dallas, Texas, on 30 January 1958, it was technology being put to use as a modern convenience. Passenger conveyors traveling at the granny-friendly speed of one-and-a-half miles per hour assisted foot traffic for the long walk in each of three concourses from the terminal lobby to the plane ramps. This was the first two-way, moving sidewalk put into service at an airport in America. It was 1,425 feet long and consisted of three loops. Each loop provided a floor-level, rubber carpet, moving continuously between two side-walls that carried a moving handrail of the kind already familiar from its use on escalators. A continuous series of wheeled pallets supported the deck, with flexible connections between them, which were also able to follow vertical or horizontal curves in their track.
In the 18 Jul 1955 issue of Time magazine, the cost was given as $234,704
As with new technology, there were unforeseen problems in the design. At first these were minor. Several persons had been caught by the sidewalk. Also a dog suffered a broken leg in the mechanism. On 26 Jan 1958, Mrs. R. E. Womack, 38, of Dallas, was sightseeing with her seven-year-old son, Robert Lee Womack. According to Patrolman R. J. Shackelford, in an Associated Press report, the boy was riding the moving seidewalk, and fell near the end of it. The youngster's T-shirt was entangled in the mechanism, and dragged him to the end of the walk. The fingers of his right hand were skinned.
When his mother knelt beside him to help, her own clothes were also caught up by the belt, and her skirt and petticoat were pulled off. She was left wearing her knee-length leather coat. The power for the sidewalk was turned off. The mother went with her frightened son to an office in the terminal.
In a later accident, a death resulted. Among the Friday night's crowd of holiday travelers, on 1 January 1960, was tiny, 2-year-old, blond Tina Marie Brandon. She was there with her family for the departure of a relative. Having never seen a moving sidewalk before, she was fascinated by it. Tina ran down the hall to the end of the slowly moving belt. Apparently, she bent down to get a closer look where the it disappeared under the step-off plate. Her coat sleeve was caught by the heavy rubber belt where it turned under at the end, and it continued to drag her clothing into the mechanism. Her left hand, left writst and half of her left forearm were pulled below floor level. She screamed, as did her brother, Wilfred, 5. Before any adult nearby could react, the girl was crushed to death by her own clothing squeezed ever tighter around her body.
After the belt was stopped, E. M. Hardy, a policeman stationed on duty at the terminal said that as he cut off part of her clothes to release her, the material was drawn so tightly around her body, that he could barely insert a knife blade underneath it.
The girl was already dead upon arrival at the hospital, where officials said she had a crushed chest and shoulder. “My child was murdered and there was nothing in the world we could do to help her,” her distraught mother, Mrs. L. C. Brandon told a newspaper reporter. “They have no tools out there at all, not even a crowbar.” The father, L. C. Brandon, the next day said he had talked to a lawyer concerning possible legal action against the city. “I don't want to get anything out of it because of her, but I think something should be done about that machine.”
The moving sidewalks at the airport remained shut down for investigation. A newspaper account of the accident reported that Dallas Mayor, R. L. Thornton, and two other city officials promised action to prevent further accidents. They were manufacturered by Hewitt-Robins Co. of Passaic, N.J., maker of industrial conveyors and materials handling equipment. Normal clearance between the rubber belt and the step-off plate was less than an inch. Their engineers were expected to make close inspections before any further use of the moving sidewalks.