Which statement best describes the general differences between Category II and III ILS minimums compared to Category I?

• A. II and III provide higher precision and lower visibility requirements than Category I.
• B. II/III require higher thresholds for both decision height and visibility.
• C. II/III have not improved precision over Category I.
• D. Category III cannot operate with lower decision height than Category I.

Answer: (A)

The key idea is that Category II and III ILS approaches are designed to allow landings in poorer weather by using more precise guidance and lower minimums than Category I. With II and III, pilots can descend to lower decision heights and operate with lower visibility requirements, thanks to enhanced guidance, stricter equipment and procedures, and additional crew training. This means you can land closer to the runway in less favorable conditions than Category I permits. The other statements misstate this relationship: II/III do not require higher DH or visibility than Category I; in fact they enable lower thresholds. And Category III can operate with even lower or no decision height in some cases, which further shows that II/III provide improved or at least more capable minima than Category I.