Low Vis Ops

Question 1

When does it apply?

Answer 1

Take off operations in less than 400m RVR

Approach and Landing operations in less than 550m RVR

Question 2

Low Vis Take Off

Answer 2

Absolute Take Off Minimums :

75/75/75 (with at least one PVD)
125/125/125 (No PVD)

These values are the lowest possible RVRs - higher limits may apply - check AOI pages

For take off operations with any RVR element below 200m all 3 RVRs are required to be at or above the appropriate minimum value.

Question 3

Low Vis Landing

Answer 3

Absolute landing minima:

75/75/75* (CAT 3B)

Minima/125/75* (CAT 3A or greater)

The minimum value for the midpoint is 125m or the TDZ RVR if that is lower.

*If crew deem the stop end RVR is relevant, it is controlling and is always required to be 75m.

(Relevant means part of the runway uses during the high speed phase of landing down to around 60kts)

Question 4

To Autoland or not?

Answer 4

Any approach in minima lower than CAT1 must be followed by an autoland (and auto roll out if possible) this includes LTS Cat 1/2 approaches!

Crew many only attempt to autoland on a runway for which LVO minima are published, even in CAT 1 conditions.

Question 5

LTS Cat 1 and OTS Cat 2 Approaches

Answer 5

European only low vis approaches.

LTS Cat 1 approaches permit a minimum RVR of 400m

OTS Cat 2 approaches permit a minimum RVR of 350m

In each case, an autoland is required. Possibility of missed approach higher as some elements of ground infrastructure may not be present.

Question 6

Runway Coded Centreline Lights

Answer 6

Red and white alternating lighting starts at 900m remaining (should be 90kts)

Continuous red lighting starts at 300m remaining (should be be 30kts)

Useful on short runways to check speed against distance (eg SAN)

Question 7

Alert height

Answer 7

200 Radio

Question 8

Autoland Capability

Answer 8

LAND3 - CAT3B
LAND2 - CAT3A
NO AUTOLAND - CAT1

Autoland not allowed with:

SLATS DRIVE
SINGLE SOURCE ILS
SINGLE SOURCE RAD ALT
SINGLE SOURCE DISPLAYS

Automatic aural alerting of landing minima is mandatory for all CAT 3 operations. Appropriate CAT 3A Radio DH must be set when reverting from CAT 3B to CAT 3A.

Question 9

Pilot Assessment of RVR

Answer 9

You only see slant range therefore assume you can’t see first light. (RVR of 150 m with 15 m light spacing, you should see 9 lights)

Question 10

LVO procedures in force when….

Answer 10

“Low visibility procedures in force or CAT 3 approaches in use etc.”

Or in USA:

LVP’s are implicit if the cloud base <800’ and/ or visibility is <2sm.

Question 11

RVR and CMV

Answer 11

A conversion from MET visibility to RVR (CMV) may NOT be used if:

• RVR is reported
• Calculating Take-Off minima
• For landing when the RVR required is less than 800m

On Lido charts RVR / CMV values are shown without a limiting letter. If a letter (R or V) follows the published value, then NO conversion is allowed.

Use flow chart if MET to RVR is allowed.