The craft was hovering just above a telephone pole. I was heading towards Grand Forks Air Force Base. I stopped my car and watched the craft from approximately 75 to 100 feet across the highway. It was stationary and of unknown aircraft type. As a staff sergeant in the Communications field I knew all the aircraft the services had and this craft was completely unknown and acting like nothing I had ever seen or heard about. The craft was completely black with no markings. It was approximately 25 feet long with a narrow body with wings swept forward nearly touching the front of the craft. I watched it for 15 minutes until it left flying west at a high angle and disappeared in 5 seconds. It made no sound that I could detect. This is the first time I have told anyone about the sighting.