What ground equipment is required for CAT II operations?

For Category II (CAT II) operations, the key requirement is the presence of both a Localizer (LOC) and a Glide Slope (GS) in conjunction with an Outer Marker (OM) or an acceptable substitute. This combination is essential for providing the necessary precision guidance for approaches in lower visibility conditions.

CAT II operations are designed to allow aircraft to land with a decision height typically ranging from 100 feet to 200 feet above the runway, compared to CAT I operations which have higher decision heights. The LOC provides lateral guidance to ensure that the aircraft remains aligned with the centerline of the runway, while the GS offers vertical guidance to facilitate a safe descent path. The inclusion of an OM or a substitute helps improve the reliability of the approach by providing additional data points for pilots to determine their positions during the landing phase.

Other choices do not meet the requirements for CAT II operations. For instance, relying solely on an Instrument Landing System (ILS) without consideration for the necessary components like LOC and GS does not provide a complete picture of what is needed for safe landings under CAT II conditions. Similarly, having just a VOR or a radar altimeter would not suffice, as they do not offer the precise approach guidance necessary for this level of operation