Short answer: A navaid upgrade and approach minima reduction study checks whether improving ILS, DME/DME, VOR/DME, SBAS, GBAS or another navigation capability can lower approach minima and increase usable operating time for a specific airport or runway under local weather conditions.
What makes the business case reliable
- Historical ceiling, visibility, wind and RVR analysis.
- Current and candidate procedure minima comparison.
- Obstacle and terrain limits on achievable OCA/H.
- Runway lighting, marking and infrastructure constraints.
- Fleet equipage and operational approval assumptions.
- Expected recovered operations during low visibility periods.
- Cost, implementation complexity and maintenance impact.
- Clear recommendation on whether the upgrade is worth it.
Why weather matters
A theoretical minima reduction has limited value if local meteorology rarely falls between the old minima and the new minima. The study should quantify how often the upgraded procedure would recover real operations.
Quantify minima benefits
Use weather, procedure and infrastructure data to decide before investing.