The highest accuracy approaches are the CAT III approaches that may provide guidance all the way to the runway with no requirement for decision height (CAT IIIB) nor for runway visual range (CAT IIIC).
Category | Decision Height (DH) | Runway Visual Range (RVR) |
CAT I | DH 200 ft | RVR 550 m (helicopters 500 m) |
CAT II | DH 100 ft | RVR 300 m |
CAT IIIA | DH 100 ft | RVR 200 m |
CAT IIIB | no DH | 75 m (ICAO SARPS: 50 m) |
EASA AIR OPS
Annex I Definitions for terms used in Annexes II to VIII
(14) ‘category II (CAT II) operation’ means a precision instrument approach and landing operation using ILS or MLS with:
(a) DH below 200 ft but not lower than 100 ft; and
(b) RVR of not less than 300 m;
(15) ‘category IIIA (CAT IIIA) operation’ means a precision instrument approach and landing operation using ILS or MLS with:
(a) DH lower than 100 ft; and
(b) RVR not less than 200 m;
(16) ‘category IIIB (CAT IIIB) operation’ means a precision instrument approach and landing operation using ILS or MLS with:
(a) DH lower than 100 ft, or no DH; and
(b) RVR lower than 200 m but not less than 75 m;
Please let us know if you come across this question in your official exam. Considering the current correct option, we believe that the examiner does not take into account CAT IIIC which requires no decision height and no runway visual range.
Learning Objective 062.02.05.04.02: Define the following ILS operation categories: Category I; Category II; Category IIIA; Category IIIB; Category IIIC.
Your Notes (not visible to others)
This question has appeared on the real examination, you can find the related countries below.
-
Austro Control2
-
Germany1
-
United Kingdom1