The Polaris A-1 was a fleet ballistic missile built by Lockheed Missiles and Space Company. It had a diameter of 4 feet 6 inches, a length of 28 feet, a weight of 28,000 pounds, no wing or fin span, a solid propellant power plant, hypersonic speed, a range of 1,380 miles, inertial and celestial guidance, and nuclear armament. The Navy ordered five existing submarines to be modified to carry the Polaris missile. The first modified submarine was SSBM 598 George Washington, originally SSN 598 Scorpion, and all five renovated submarines became known as the George Washington class. During launch, the missile was ejected vertically through a hatch on the deck of the submarine. The Polaris A-1 was officially retired from service in October 1965 when the last George Washington class submarine, the Abraham Lincoln, returned to port.