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Precision approach – Category I operations

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Precision approach — Category I operations

1. General
A Category I operation is a precision instrument approach and landing using ILS, MLS or PAR with a decision height not lower than 200 ft and with a runway visual range not less than 550 m.

2. Decision height
An operator must ensure that the decision height to be used for a Category I precision approach is not lower than:
(i) The minimum decision height specified in the Aeroplane Flight Manual (AFM) if stated;
(ii) The minimum height to which the precision approach aid can be used without the required visual reference;
(iii) The OCH/OCL for the category of aeroplane; or
(iv) 200 ft.

3. Visual reference
A pilot may not continue an approach below the Category I decision height, determined in accor- dance with subparagraph (c)2. above, unless at least one of the following visual references for the intended run- way is distinctly visible and identifiable to the pilot:
(i) Elements of the approach light system;
(ii) The threshold;
(iii) The threshold markings;
(iv) The threshold lights;
(v) The threshold identification lights;
(vi) The visual glide slope indicator;
(vii) The touchdown zone or touchdown zone markings;
(viii) The touchdown zone lights; or
(ix) Runway edge lights.

4. Required RVR
The lowest minima to be used by an operator for Category I operations are:

Table 5
RVR for Cat I approach v. facilities and DH

Category I minima

Decision height (Note 7)Facilities/RVR (Note 5)
Full
(Notes 1 and 6)
Interm
(Notes 2 and 6)
Basic
(Notes 3 and 6)
Nil
(Notes 4 and 6)
200 ft550 m700 m800 m1000 m
201-250 ft600 m700 m800 m1000 m
251-300 ft650 m800 m900 m1200
301 ft and above800 m900 m1000 m1200

Note 1: Full facilities comprise runway markings, 720 m or more of HI/MI approach lights, runway edge lights, threshold lights and runway end lights. Lights must be on.
Note 2: Intermediate facilities comprise runway markings, 420-719 m of HI/MI approach lights, runway edge lights, threshold lights and runway end lights. Lights must be on.
Note 3: Basic facilities comprise runway markings, <420 m of HI/MI approach lights, any length of LI approach lights, runway edge lights, threshold lights and runway end lights. Lights must be on.
Note 4: Nil approach light facilities comprise runway markings, runway edge lights, threshold lights, runway end lights or no lights at all.
Note 5: The above figures are either the reported RVR or meteorological visibility converted to RVR in accordance with para- graph (h).
Note 6: The Table is applicable to conventional approaches with a glide slope angle up to and including 4° (degree).
Note 7: The DH mentioned in the Table 5 refers to the initial calculation of DH. When selecting the associated RVR, there is no need to take account of a rounding up to the nearest 10 feet, which may be done for operational purposes, (e.g. conversion to DA).

5. Single pilot operations
For single pilot operations, an operator must calculate the minimum RVR for all approaches in accordance with the Aerodrome operating minima and this Appendix. An RVR of less than 800 m is not permitted except when using a suitable autopilot coupled to an ILS or MLS, in which case normal minima apply. The Decision Height applied must not be less than 1,25 x the minimum use height for the autopilot.

6. Night operations
For night operations at least runway edge, threshold and runway end lights must be on.

Source: EU-OPS

See also:
Fail-Operational flight control system
Fail-Passive flight control system
Precision approach – Category I operations
Precision approach – Category II operations
Precision approach – Category III operations

The presented material is for training purpose only!