An obsolete plane
The plane had something out of the ordinary, it was a very old plane. The operators could not believe their eyes. It was something unusual and almost impossible to see this kind of plane nowadays.
The plane he noticed was an extremely old airliner with propellers that were no longer used for commercial flights, so he made some assumptions. They quickly passed the information on to their superiors, because they did not know the procedure to follow for this type of aircraft. Juan and his colleagues gathered at the watchtower window and watched this spectacle with overwhelming amazement. It got even stranger when they got a call from the plane.