An enhanced flight vision system (EFVS, sometimes EVS) is an airborne system which provides an image of the scene and displays it to the pilot, in order to provide an image in which the scene and objects in it can be better detected. In other words, an EFVS is a system which provides the pilot with an image which is better than unaided human vision. An EFVS includes imaging sensors (one or many) such as a color camera, infrared camera or radar, and typically a display for the pilot, which can be a head-mounted display or head-up display. An EFVS may be combined with a synthetic vision system to create a combined vision system.

An EFVS can be mounted on military or civilian aircraft, fixed wing (airplane) or rotary wing (helicopter). The image must be displayed to the pilot conformal to the scene, i.e. the pilot must see the artificially displayed elements in exact positions relative to the real world. Usually along with the enhanced image, the system will display visual cues such as a horizon bar and runway location.

Enhanced vision is a related to Synthetic vision system which incorporates information from aircraft based sensors (e.g., near-infrared cameras, millimeter wave radar) to provide vision in limited visibility environments.

Night vision systems have been available to pilots of military aircraft for many years. More recently business jets have added similar capabilities to aircraft to enhance pilot situational awareness in poor visibility due to weather or haze, and at night. The first civil certification of an enhanced vision system on an aircraft was pioneered by Gulfstream Aerospace using a Kollsman IR camera. Originally offered as an option on the Gulfstream V aircraft, it was made standard equipment in 2003 when the Gulfstream G550 was introduced and followed on the Gulfstream G450 and Gulfstream G650. As of 2009, Gulfstream has delivered over 500 aircraft with a certified EVS installed. Other aircraft OEMs followed, with EVS now available on some Bombardier and Dassault business jet products. Boeing has begun offering EVS on its line of Boeing business jets and is likely to include it as an option on the B787 and B737 MAX.

The Gulfstream EVS and later EVS II systems use an IR camera mounted in the aircraft's nose to project a raster image on the head-up display (HUD). The IR image on the HUD is conformal to the outside scene, meaning that objects detected by the IR camera are the same size and aligned with objects outside the aircraft. Thus in poor visibility the pilot is able to view the IR camera image and is able to seamlessly and easily transition to the outside world as the aircraft gets closer.

The advantage of EVS is that safety in nearly all phases of flight are enhanced, especially during approach and landing in limited visibility. A pilot on a stabilized approach is able to recognize the runway environment (lights, runway markings, etc.) earlier in preparation for touchdown. Obstacles such as terrain, structures, and vehicles or other aircraft on the runway that might not otherwise be seen are clearly visible on the IR image.

The FAA grants some additional operating minimums to aircraft equipped with certified enhanced vision systems allowing Category I approaches to Category II minimums. Typically an operator is permitted to descend to lower altitudes closer to the runway surface (typically as low as 100 ft) in poor visibility in order to improve the chances of spotting the runway environment prior to landing. Aircraft not equipped with such systems would not be allowed to descend as low and often would be required to execute a missed approach and fly to a suitable alternate airport.

Other sensor types have been flown for research purposes, including active and passive millimeter wave radar. In 2009, DARPA provided funding to develop "Sandblaster", a millimeter wave radar based enhanced vision system installed on helicopters which enables the pilot to see and avoid obstacles in the landing area that may be obscured by smoke, sand, or dust.