Enhanced Vision Systems (EVS)

This page provides guidance and links to Safety Requirements for Air Traffic Service (ATS) Providers and Aerodrome Licence Holders wishing to implement Enhanced Vision Systems operations.

Overview

An EVS uses modern technology (currently infra-red) to overlay an image of the surrounding topography on a head up display allowing the pilot to see the surrounding terrain in low visibility conditions.

Using an EVS, a pilot may continue an approach below Decision Height (DH) or Minimum Descent Height (MDH) to 100ft above the threshold elevation of the runway provided at least one of the visual references prescribed in EU-OPS is displayed and identifiable on the EVS. A pilot may not continue an approach below 100 ft above the runway threshold elevation unless at least one of the visual references prescribed in EU-OPS is distinctly visible and identifiable to the pilot without reliance on the EVS.

Suitably approved aircraft operators will be able to conduct approaches in reduced Runway Visual Range (RVR), down to a minimum of 350 m. Table 9 of EU-OPS, Subpart E (All Weather Operations) Ops 1.430, Appendix 1 (New) paragraph (h) gives the reduction allowed to the RVR normally required, if using an EVS.

The detailed requirements for EVS are published in EU-OPS, Subpart E (All Weather Operations) Ops 1.430, Appendix 1 (New), paragraph (h).

Regulatory Requirements

These operations do not require any changes to Navigation Infrastructure or Aeronautical Ground Lighting.

Note: Aerodrome operators should be aware there may be an issue with the introduction of Light Emitting Diode (LED) lighting systems as LED infrared signatures are not compatible with existing EVS equipment.

Low Visibility Requirements

As lower RVR values will be used at the aerodrome, it will be necessary to review and where necessary revise Low Visibility Procedures (LVPs) in the Aerodrome Manual and the Manual of Air Traffic Services Part 2, to ensure their compatibility with operations at the lower RVR values.

The requirements contained in CAP 493 and CAP 168 Chapter 2 Appendix 2B Low Visibility Operations remain applicable.

Phraseology

No new phraseology has been promulgated for EVS operations.  It is considered that the Low Visibility Procedures will be sufficient for Air Traffic Control (ATC) to manage all aircraft operating to the minimum RVR value.

Instrument Approach Procedure

Even though a lower RVR value is used there is no change to the type of operation (e.g. Non Precision Approach or CAT I).  There is no requirement to change the design of any Instrument Approach Procedure.

Runway Visual Range

Even though a lower RVR value is used there is no change to the type of operation.   It will be necessary to ensure that the minimum RVR is able to be presented on the RVR display.

Instrument Runway Visual Range requirements remain applicable as prescribed in CAP 670 NAV 01.

Promulgation

To assist Aircraft Operators to assess whether the Low Visibility Procedures are acceptable for EVS operations, it will be necessary to promulgate in the AIP section AD 2.20 Section 6 “Use of Runways” the operations that are being offered.

Examples of AIP entries are shown below.

Runway XX suitable for EVS operations.

Note: Work is on-going with in the CAA to develop a dedicated EU OPS heading in AD 2.20.

Related Information