GM5 NCO.OP.110 Aerodrome operating minima – aeroplanes and helicopters

CAA ORS9 Decision No. 47

Text in magenta in force from 30 October 2025

CONVERSION OF REPORTED METEOROLOGICAL VISIBILITY TO RVR/CMV

1. A conversion from meteorological visibility to RVR/CMV should not be used:

1. when reported RVR is available;

2. for calculating take-off minima; and

3. for other RVR minima less than 800 m.

2. If the RVR is reported as being above the maximum value assessed by the aerodrome operator, e.g. ‘RVR more than 1 500 m’, it should not be considered as a reported value.

3. For all other circumstances, Table 5 should be used.

Table 5: Conversion of reported meteorological visibility to RVR/CMV

Lighting elements in operation	RVR/CMV = reported meteorological visibility x
	Day	Night
High intensity (HI) approach and runway lights	1.5	2.0
Any type of light installation other than above	1.0	1.5
No lights	1.0	not applicable

The text below will replace the text above on 30 October 2025:

EFFECT OF TEMPORARILY FAILED OR DOWNGRADED GROUND EQUIPMENT ON LANDING MINIMA

1. Lighting in Table 5 should be considered only if the relevant lighting is operating. For example, if components of a FALS have failed leaving only the last 250 m operating normally, the lighting facilities should be treated as BALS.

2. Failures of standby equipment, standby power systems, middle markers and RVR assessment systems have no effect on minima.