Commercial airplanes typically fly at cruising altitudes between 31,000 and 42,000 feet (5.9 to 7.2 miles) above sea level. The exact altitude depends on several factors, including the type of aircraft, the distance it is traveling, the type of engine it has, its weight, and the current strength of the winds. The cruising altitude is the height at which air offers the least resistance, allowing planes to travel faster with less fuel. Planes can fly higher than their cruising altitude, but this can present safety issues and is not the most efficient use of fuel. Smaller aircraft, whether commercially operated or not, will fly at lower altitudes, often below 15,000 feet. The minimum altitude for commercial planes is 10,000 meters (32,808 feet) . The FAA and ATC officials plan carefully to make sure that every aircraft takes off, lands, and gets to where they are going without issue, and there are thousands of flights in the sky at any given moment.