The F-4 Phantom was designed as a fleet defense fighter for the U.S. Navy, and first entered service in 1960. By 1963, it had been adopted by the U.S. Air Force for the fighter-bomber role. When production ended in 1981, 5,195 Phantom IIs had been built, making it the most numerous American supersonic military aircraft. Until the advent of the F-15 Eagle, the F-4 also held a record for the longest continuous production with a run of 24 years. Innovations in the F-4 included an advanced pulse-doppler radar and extensive use of titanium in the airframe.  QF-4 Phantom 74-626 at McGuire Air Force Base, 12 May 2007. An A-10 Thunderbolt II can be seen in the background.  Despite the imposing dimensions and a Maximum Takeoff Weight of over 60,000 pounds (27,000 kg), the F-4 was capable of reaching a top speed of Mach 2.23 and had an initial climb rate of over 41,000 feet per minute (210 m/s). Shortly after its introduction, the Phantom set 16 world records, including an absolute speed record of 1,606.342 miles per hour (2,585.086 km/h), and an absolute altitude record of 98,557 feet (30,040 m). Although set in 1959-1962, five of the speed records were not broken until 1975.  The F-4 could carry up to 18,650 pounds (8,480 kg) of weapons on nine external hardpoints, including air-to-air and air-to-ground missiles, and unguided, guided, and nuclear bombs. Since the F-8 Crusader was to be used for close combat, the F-4 was designed, like other interceptors of the day, without an internal cannon. Air combat experience over North Vietnam led to the adoption of the Phantom by both the Navy and Air Force as the primary air superiority fighter of both services. Its large wing and powerful engines gave it competitive performance against smaller MiGs, and the weapons systems officer assisted in spotting opposing fighters in visual range dogfights as well as with radar.  Due to its widespread service with United States military and its allies and distinctive appearance, the F-4 is one of the best-known icons of the Cold War. It served with distinction in Vietnam War and Arab-Israeli conflicts, with F-4 crews achieving 393 aerial victories and completing countless ground attack sorties. The F-4 Phantom has the distinction of being the last United States fighter to attain ace status in the 20th century. During the Vietnam War, the USAF had one pilot and Weapon systems officer (WSO), and the USN had one pilot and Radar Intercept Officer (RIO), become aces by shooting down 5 or more enemy aircraft in air to air combat. It was also a capable tactical reconnaissance and Wild Weasel (suppression of enemy air defenses) platform, seeing action as late as 1991, during Operation Desert Storm.  The F-4 Phantom II was also the only aircraft used by both of the USA’s flight demonstration teams. The USAF Thunderbirds (F-4E) and the USN Blue Angels (F-4J) both switched to the Phantom for the 1969 season; the Thunderbirds flew it for five seasons, the Blue Angels for six.  The baseline performance of a Mach 2 class fighter with long range and a bomber sized payload would be the template for the next generation of large and light/middle-weight fighters optimized for daylight air combat. The Phantom would be replaced by the F-15 Eagle and F-16 Fighting Falcon in the US Air Force. In the US Navy, it would be replaced by the F-14 Tomcat and the F/A-18 Hornet which revived the concept of a dual-role attack fighter. The General Dynamics F-111 succeeded the Phantom as a medium bomber.