Many passengers experience take-off as a familiar sequence: the engines roar to life, the aircraft accelerates down the runway, takes off, and climbs steeply. However, it is often just as noticeable when the aircraft suddenly levels off while still at a relatively low altitude. In the United States, a common interim level-off is at 10,000 feet (3,050 meters), although this varies by airport, air traffic conditions, and other circumstances.