The McDonnell Douglas F/A-18 Hornet is a twin-engine, supersonic, all-weather, carrier-capable multirole combat jet designed as both a fighter and attack aircraft. Designed by McDonnell Douglas, now Boeing, and Northrop, it was derived from Northrop's YF-17 in the 1970s for use by the United States Navy and Marine Corps, and it has also been used by the air forces of several other nations and, beginning in 1996, by the U.S. Navy's Flight Demonstration Squadron, the Blue Angels. The Hornet was among the first aircraft to make heavy use of multifunction displays, allowing a pilot at the push of a button to perform fighter or attack roles or both, giving operational commanders greater flexibility in fast-changing battle scenarios. It was the first Navy aircraft to incorporate a digital multiplexing avionics bus, enabling easy upgrades. It was also designed to reduce maintenance and has required far less downtime than heavier counterparts such as the F-14 Tomcat and the A-6 Intruder; its mean time between failures is three times greater than any other Navy strike aircraft, and it requires half the maintenance time. Its General Electric F404 engines were designed with operability, reliability, and maintainability first, and while unexceptional in rated performance, they proved exceptionally robust under various conditions and resistant to stall and flameout. The F404 engine connects to the airframe at only 10 points and can be replaced without special equipment, with a four-person team able to remove the engine within 20 minutes.