OMA 8.4 All Weather Operations (Low Visibility Operations) Flashcards Preview

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Flashcards in OMA 8.4 All Weather Operations (Low Visibility Operations) Deck (12):
1

Explain Approach Ban

Policy regarding an approach ban may differ from country to country. Usually the final approach segment may not be continued beyond the OM or equivalent DME distance if the reported RVR is below the published minima. After OM or equivalent, if RVR becomes lower than the minima, the approach may be continued.

The Approach Ban point is either FAF (i.e. glide slope interception point) or 1000 ft AAL or (OM) Outer Marker and if no OM exists then this is replaced by equivalent position.

The ‘equivalent position' mentioned here can be established by the means of a DME distance, a suitably located NDB or VOR, or any other suitable fix that independently establishes the position of the aeroplane.

2

Commencement and Continuation of an Approach (LVO)

The Commander may commence an instrument approach regardless of the reported RVR/visibility but the approach shall not be continued beyond the Approach Ban point, if the reported RVR/visibility is less than the applicable minima.

If, after passing the Approach Ban point, the reported RVR/visibility falls below the applicable minimum, the approach may be continued to DA/H.

When no outer marker or equivalent position exists, the commander or the pilot to whom conduct of the flight has been delegated shall make the decision to continue or abandon the approach before descending below 1000 feet above the aerodrome on the final approach segment.

The conversion of visibility to RVR is not applicable to CAT II/III approach.

3

Which RVRs are controlling?

The touchdown zone RVR is always controlling. If reported and “relevant”, the midpoint and stop-end RVR also controlling.

The minimum RVR value for Mid Point is 125m or the RVR required for Touch Down Zone if less, and 75 m for the stop end. For aeroplane equipped with roll out guidance or control system, the minimum RVR value for the midpoint is 75m.

Note: “Relevant”, in this context, means that part of the runway used during the high speed phase of the landing down to a speed of approximately 60 kt.

4

Aircraft Stabilization on Approach - CAT II / III
....ft

For CAT II/III Approaches it is a requirement to be stabilized no later than 1500 feet AGL.

5

Requirement for LVO operations

Aircraft certification

Flight Crew are trained and qualified

Runway is certified

AUTHORITY approval

LVO procedure is in force

6

Explain Alert Height (AH)

A height above the runway based on the characteristics of the aircraft and its fail operational landing system, above which a Category III approach would be discontinued and a missed approach initiated if a failure occurred in one of the redundant parts of the fail operational landing system, or in the relevant ground equipment. In AH concept is Applicable to Only CAT IIIB operations with NO decision Height

In other AH Definition, it is generally stated that if a failure affecting the fail-operational criteria occurs below the AH, it would be ignored and the approach continued (except if AUTOLAND warning is triggered). The AH concept is relevant when CAT3 DUAL is displayed on FMA (A330).

For the A330 and B787, the AH = 200 feet.

7

Requirement for LVO operations

Aircraft certification

Flight Crew are trained and qualified

Runway is certified

AUTHORITY approval

LVO procedure is in force

8

Explain Alert Height (AH)

A height above the runway based on the characteristics of the aircraft and its fail operational landing system, above which a Category III approach would be discontinued and a missed approach initiated if a failure occurred in one of the redundant parts of the fail operational landing system, or in the relevant ground equipment. In AH concept is Applicable to Only CAT IIIB operations with NO decision Height

In other AH Definition, it is generally stated that if a failure affecting the fail-operational criteria occurs below the AH, it would be ignored and the approach continued (except if AUTOLAND warning is triggered). The AH concept is relevant when CAT3 DUAL is displayed on FMA (A330).

For the A330 and B787, the AH = 200 feet.

9

A pilot may not continue a precision approach CAT II/III below the specified DH determined for such operations unless following visual references is attained and can be maintained.

CAT II

A segment of at least 3 consecutive lights being:

a) The centre line of the approach lights, or
b) Touchdown zone lights, or
c) Runway centre line lights, or
d) Runway edge lights, or
e) A combination of these is attained and maintained.

This visual segment must include a lateral element of the ground pattern:
a) An approach lighting crossbar, or
b) The landing threshold, or
c) A barrette of the touchdown zone lighting.

10

A pilot may not continue a precision approach CAT II/III below the specified DH determined for such operations unless following visual references is attained and can be maintained.

CAT III A

A segment of at least 3 consecutive lights being:

a) The centre line of the approach lights, or
b) Touchdown zone lights, or
c) Runway centre line lights, or
d) Runway edge lights, or
e) A combination of these is attained and maintained.

11

A pilot may not continue a precision approach CAT II/III below the specified DH determined for such operations unless following visual references is attained and can be maintained.

CAT III B with fail operational flight control system with DH

At least one centre line light is attained and maintained

12

A pilot may not continue a precision approach CAT II/III below the specified DH determined for such operations unless following visual references is attained and can be maintained.

CAT III B with no DH

No requirement of visual contact prior to touchdown