Commercial aircraft operate at elevations from ranging 30,000 to 45,000 feet and fly at speeds greater than 500 miles per hour. To achieve this, aircraft are powered by engines that spin at rates from 10,000 to 25,000 revolutions per minute. The reliable operation of these aircraft is a testament to the quality of modern aircraft engineering, aircraft maintenance & repair, and the quality of tools used to build and repair aircraft. The power and speed of aircraft result in a great deal of force being exerted on each part of the aircraft. Because of this, every single part of an aircraft, down to the last nut and bolt, must be secured in place properly.