Полёт на предельно малой высоте: тактика и особенности

Very low altitude flight technique

Nap of the earth (NOE) is a type of very low altitude flight course used by military aircraft to avoid enemy detection and attack in a high threat environment. "ground hugging", "terrain masking", "flying under the radar" and "hedgehopping". During NOE flight, geographical features are used as cover, exploiting valleys and folds in the terrain by flying in, rather than over, them. This keeps the aircraft below enemy air defence radar coverage, avoiding being silhouetted against the sky.

NOE is used to minimize detection by hostile aircraft, airborne early warning and control surveillance and control systems, ground based radar, or attack targets.

Most NOE flying is done during the day using visual reference by pilots who are experienced in low flying. Data from a radar altimeter or terrain following radar system is also used, the latter enabling low flying in adverse weather where it would not be possible by visual reference and manual pilot control. At night, a night vision device may be used.

The lowest NOE flying is by helicopters because they have lower speeds and more maneuverability than fixed wing aircraft, particularly fast jets. Helicopters can fly at treetop levels or even below the height of surrounding trees where there are clear areas (such as in river gullies), flying under wires (such as electricity cables) rather than over them. Attack helicopters can hide behind trees or buildings, "popping up" with minimum exposure, just enough to use their (rotor mast mounted) radar or other sensors and launch weapons. The required altitude depends on the type of terrain, such as low vegetation or low buildings, tree canopy layer of less than , presence of tall buildings or concrete pylons with heights of up to international standard, or emergent tree layer canopy and lattice steel electricity pylons to being present. In populated areas with tall radio transmission towers, an altitude of above ground level applies.

Height above ground level in NOE and low flying generally vary with the aircraft speed, aircraft maneuverability and the ruggedness of the terrain. Helicopters are capable of flying with no more than a few feet of clearance below the helicopter's skids or wheels. Fast jets are more constrained and at a typical low flying speed of , 200 feet (61 m) is not unusual and 50 feet (15 m) is possible in relatively flat terrain. Power wires are a danger to all aircraft flying at low level and "wire strikes" are common, such as the 1998 Cavalese cable car crash. Special maps are produced that plot the routes of these wires but these are difficult to keep up to date, especially for foreign/enemy countries. Pilots are trained to scan for the pylons or power poles that support these wires, because they can be seen at a distance where the wires themselves cannot.