Stage 3 noise compliant after 31 December 2015. The Falcon 20 was listed explicitly in Federal Register 78 FR 39576. Any examples of the type that were not been modified, either by the installation of Stage 3 noise-compliant engines or have had hush kits installed upon noncompliant engines, were no longer permitted to fly anywhere in the contiguous 48 states after 31 December 2015. However, 14 CFR §91.883 Special flight authorizations for jet airplanes weighing 75,000 pounds or less – lists special flight authorizations that may be granted for operation after 31 December 2015. Design The Dassault Falcon 20 is a French business jet, often considered to be an easy to fly and relatively visually appealing aircraft. The favourable flight qualities of the aircraft meant that no need existed to incorporate a stick pusher or stall-barrier systems to achieve its predictable stall behaviour. The flight controls of the Falcon 20 are hydraulically powered, augmenting the mechanical pushrods between the cockpit controls and the flight control surfaces. In the event of complete hydraulic failure, the aircraft can be practically flown without any augmentation. The controls incorporate an artificial feel system, optimising the sensations perceivable to the operating pilot to be smooth, predictable, and precise. On the Falcon 200, the cockpit is heavily modernised, being more comparable with the newer Falcon 50 than the original Falcon 20. The Falcon 20 is powered by a pair of rear-mounted turbofan engines; most commonly powered by a pair of General Electric CF700 engines, the type has also been powered by alternative powerplants, including the Garrett TFE731 and ATF3 engines. The adoption of newer engines often had the benefit of improving the Falcon 20's range in addition to increased speed and climb rate; this, in combination with its low-drag fuselage, required more careful speed planning than the majority of business jets. On some models, protection against engine conditions such as instances of over-speed and over-heating is provided by electronic flight computers, as is the aircraft's 'throttle-lock' power management system to maintain safe levels of engine power throughout climbs without any crew commands. As conventional thrust reversers are not compatible with the location of the engines, an alternative configuration in the form of rotatable doors fixed to the outer cowling of the engine partially cover both the engine fan and core exhaust, deflecting thrust upwards and forwards. The Falcon 20 is furnished with a highly swept wing;