The lowest-visibility precision ILS approaches, allowing landings in extremely poor weather using advanced aircraft systems, ground equipment, and specially trained crews. CAT III approaches are subdivided into three levels based on Decision Height (DH) and Runway Visual Range (RVR) requirements.
Key characteristics:
- CAT IIIa:
- DH: below 100 ft (or no DH)
- RVR: ≥ 200 meters
- DH: below 100 ft (or no DH)
- CAT IIIb:
- DH: below 50 ft (or no DH)
- RVR: ≥ 75 meters
- DH: below 50 ft (or no DH)
- CAT IIIc:
- No DH
- No RVR minimums (theoretical “zero-zero” landing capability, requiring full autoland and rollout guidance).
Other considerations:
- Ground equipment: Highly accurate ILS transmitters, advanced approach lighting, runway monitoring systems, and sometimes rollout guidance.
- Aircraft requirements: Autoland systems (dual/triple autopilot redundancy, fail-operational capability), radio altimeter, and certified avionics.
- Crew requirements: Intensive CAT III training, special approval, and recurrent checks.
Application in DCS World
- DCS aircraft with autopilot-coupled ILS (e.g., F/A-18C, F-16C, A-10C) can simulate approaches into very low visibility, down to near-zero decision points if the mission weather is set that way.
- DCS does not model true CAT III systems: no rollout guidance, no dual/triple autopilot certification, no autoland categories, and no RVR enforcement. CAT IIIc “zero-zero” landings are not realistically possible.
Cadets can simulate CAT III-style training by flying ILS approaches in near-zero visibility, practicing disciplined instrument scans and blind runway intercepts. This reinforces instrument precision, though real-world CAT III procedures remain theoretical in DCS.