Chapter 2.2

Transcript

1. 2.1 Category II 2.2 Category III 2.3 Decision Height and Alert Height 2.4 Runway Visual Range 2.5 Fail-passive Autoland System 2.6 Fail-operational Autoland System 2.7 Minimum Approach Break-off Height 2.8 Concept of Minima Module 2 - General Concepts
2. A CAT III operation is a precision approach at lower than CAT II minima. CAT Ill is divided in three sub-categories: CAT III A, CAT III B, and CAT III C, associated with three minima levels (CAT III A is associated with highest minima, and CAT III C with lowest minima). Category III
3. A category III A approach is a precision instrument approach and landing with no decision height or a decision height lower than 100 ft (30 m) and a runway visual range not less than 700 ft (200 m). ICAO and FAA CAT III Definitions
4. A category III A approach is a precision instrument approach and landing with a decision height lower than 100 ft (30 m) and a runway visual range not less than 700 ft (200 m). It is worth noting that the JAA considers that CAT III A is always associated with a decision height (difference with ICAO/FAA). JAA CAT III Definitions
5. A category III B approach is a precision approach and landing with no decision height or a decision height lower than 50 ft (15 m) and a runway visual range less than 700 ft (200 m), but not less than 150 ft (50 m). ICAO and FAA CAT III B Definitions
6. A category III B approach is a precision approach and landing with no decision height or a decision height lower than 50 ft (15 m) and a runway visual range less than 700 ft (200 m), but not less than 250 ft (75 m). Notes: ICAO/FAA and JAA differ by the minimum RVR associated with CAT III B approaches (50 m / 75 m). JAA: Where the DH and the RVR do not fall in the same Category, the RVR will determine in which Category (CAT III A or B) the operation is to be considered. JAA CAT III B Definitions
7. A category III C approach is a precision approach and landing with no decision height and no runway visual range limitation. CAT III C operations are not currently authorized and the JAA does not mention this sub-category. Note from ICAO document: Where the DH and RVR do not fall within the same Category, either the DH or the RVR may determine in which Category the operation is to be considered. The operation will be in the Category with the lower minima. ICAO and FAA CAT III C Definitions
8. The main objective of CAT Ill operations is to provide a level of safety equivalent to other operations but in the most adverse weather conditions and associated visibility. In contrast to other operations, CAT III weather minima do not provide sufficient visual references to allow a manual landing to be made. The minima only permit the pilot to decide if the aircraft will land in the touchdown zone (basically CAT III A) and to ensure safety during rollout (basically CAT III B). CAT III Objective
9. Therefore, an automatic landing system is mandatory to perform Category III operations. Its reliability must be sufficient to control the aircraft to touchdown in CAT III A operations and through rollout to a safe taxi speed in CAT III B (and CAT III C when authorized). Note about automatic landing: Automatic landing is not CAT III. An automatic landing system is only equipment providing automatic control of the aircraft during the approach and landing and is not related to particular weather conditions. CAT III Objective
10. This system is mandatory for all CAT III operations. However, it is a common practice to perform automatic landing in good visibility but in that case, the ILS performance must be sufficient and ILS signals protected (see Module 5). As for CAT II operations, the desired level of safety is achieved with more stringent requirements. CAT III Objective
11. CAT II and III Definition
12. Correspondence Meter/Feet (ICAO)