Question: Which jet fighter is currently in service in the United States and is to replace the United States navy's F/A-18E/F Super Hornet?
Context: The AIM-54 Phoenix is a radar-guided, long-range air-to-air missile (AAM), carried in clusters of up to six missiles on the Grumman F-14 Tomcat, its only operational launch platform.  The Phoenix was the United States' only long-range air-to-air missile.  The combination of Phoenix missile and the AN/AWG-9 guidance radar was the first aerial weapons system that could simultaneously engage multiple targets.  Both the missile and the aircraft were used by the United States Navy and are now retired, the AIM-54 Phoenix in 2004 and the F-14 in 2006.  They were replaced by the shorter-range AIM-120 AMRAAM, employed on the F/A-18 Hornet and F/A-18E/F Super Hornet.  Following the retirement of the F-14 by the U.S. Navy, the weapon's only current operator is the Islamic Republic of Iran Air Force.  Brevity code "Fox Three" was used when firing the AIM-54. The General Electric F414 is an afterburning turbofan engine in the 22,000-pound (98 kN) thrust class produced by GE Aviation.  The F414 originated from GE's widely used F404 turbofan from the McDonnell Douglas F/A-18 Hornet, enlarged and improved for use in the Boeing F/A-18E/F Super Hornet.  The engine was developed from the F412 non-afterburning turbofan planned for the A-12 Avenger II, before it was canceled. A sixth-generation jet fighter is a conceptualized class of fighter aircraft design more advanced than the fifth-generation jet fighters that are currently in service in the United States and in development in other countries.  The United States Air Force (USAF) and United States Navy (USN) are anticipated to field their first sixth-generation fighters in the 2025–30 time frame.  The USAF is pursuing development and acquisition of a sixth-generation fighter through the F-X program to complement existing platforms in service such as the Lockheed Martin F-22 Raptor.  The USN is pursuing a similar program called the Next Generation Air Dominance, likewise intended to complement and/or replace its existing aircraft such as the Boeing F/A-18E/F Super Hornet. Strike Fighter Squadron 106 (VFA-106), also known as the "Gladiators", is a United States Navy F/A-18 Hornet and F/A-18E/F Super Hornet Fleet Replacement Squadron stationed at Naval Air Station Oceana, Virginia. In current military parlance, a strike fighter is a multirole combat aircraft designed to operate primarily as an attack aircraft, while also incorporating certain performance characteristics of a fighter.  As a category, it is distinct from fighter-bombers.  It is closely related to the concept of interdictor aircraft, but it puts more emphasis on air-to-air combat capabilities as a multirole combat aircraft.  Examples of contemporary American strike fighters are the McDonnell Douglas F-15E Strike Eagle, Boeing F/A-18E/F Super Hornet, and Lockheed Martin F-35 Lightning II. The AN/APG-79 Active electronically scanned array (AESA) radar is a new development for the United States Navy's F/A-18E/F Super Hornet and Boeing EA-18G Growler aircraft, providing a high level of aircrew situational awareness.  The beam of the AESA radar provides nearly instantaneous track updates and multi-target tracking capability.  The APG-79 AESA uses transmit/receive (TR) modules populated with Gallium arsenide Monolithic microwave integrated circuits.  In the F/A-18E/F, the radar is installed in a slide-out nose rack to facilitate maintenance. The Boeing F/A-18E and F/A-18F Super Hornet are twin-engine carrier-capable multirole fighter aircraft variants based on the McDonnell Douglas F/A-18 Hornet.  The F/A-18E single-seat and F/A-18F tandem-seat variants are larger and more advanced derivatives of the F/A-18C and D Hornet.  The Super Hornet has an internal 20 mm M61 rotary cannon and can carry air-to-air missiles and air-to-surface weapons.  Additional fuel can be carried in up to five external fuel tanks and the aircraft can be configured as an airborne tanker by adding an external air refueling system. Strike Fighter Squadron 122 (VFA-122), also known as the "Flying Eagles", are a United States Navy F/A-18E/F Super Hornet and F/A-18 Hornet Fleet Replacement Squadron stationed at Naval Air Station Lemoore. Kenneth Todd "Hock" Ham (born December 12, 1964) is a retired American astronaut and a captain in the United States Navy.  Ham was selected for NASA's astronaut program in August 1998, while serving as the F/A-18E/F Super Hornet lead carrier suitability test pilot.  Ham's aviator call sign is "Hock".  As of July 2013, Captain Ham served as the Chair of the Aerospace Engineering Department at the United States Naval Academy, in Annapolis, Maryland.  Captain Ham has worked for Bigelow Aerospace in North Las Vegas as of August 2014. F/A-XX is a development and acquisition program for a future sixth-generation air superiority fighter to replace the United States Navy's F/A-18E/F Super Hornet beginning in late-2020s.  A requirement was first identified in June 2008.
Answer: sixth-generation jet fighter