Degraded Visual Environment (DVE)

Definition

• Any flight environment of reduced visibility in which situational awareness of the aircrew or control of the aircraft may be severely diminished, completely lost, or may not be maintained as comprehensively as they are during flight operations within clear or undiminished visibility. DVE conditions are further categorized into eleven different types: smoke, smog, clouds, rain, fog, snow, whiteout, night, flat light, sand, and brownout.

References

• Helicopter Flying Handbook, Federal Aviation Administration, 2019