Aviation Minima Tool

Version: Latest (2/11/26)

Overview

This web tool calculates and displays required regulatory minima for aviation approaches and procedures, supporting all categories (CAT A/B/C/D), approach types (precision, non-precision, circling), and custom user input. It enables instant compliance checking, regulatory comparison, and operational documentation.

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Latest update (2025-08-17): Added the "Circling Raise for Procedure" feature, which dynamically adjusts circling minima when any procedure’s DH/MDH or RVR exceeds circling values for the same category. This results in additional raised circling summaries per procedure to ensure safer, compliant minima, improving user visibility and operational accuracy.

Features and Logic Implemented

1. Regulatory Minima Calculation

• Uses official table-based RVR/VIS minima for all approaches and lighting facilities.
• Handles precision approaches (CAT I, RNP, GLS, PAR, LPV, LNAV/VNAV).
• Handles non-precision approaches (LOC, LOC+DME, VOR+DME, LNAV, SRA, LDA, VOR, NDB+DME, NDB).
• Handles Circling procedures (CAT A/B/C/D).
• Values are calculated per selected lighting facility, procedure type, and category.

2. Custom Business Rules

• Minimum RVR Rules:
  • Precision approaches: Cannot use RVR values below regulatory table minima.
  • Non-Precision (CDFA): Minimum RVR 750m; cannot use less.
  • Non-Precision (Non-CDFA): Minimum RVR 1000m (CAT A/B), 1200m (CAT C/D); cannot use less.
• LNAV/VNAV Approaches:
  • Minimum DH is 250ft for calculations; any lower value automatically raised.
• Non-Precision, MDH >1200ft Rule:
  • If user MDH is above 1200ft for any non-precision procedure, system forces Non-CDFA and RVR value is 5000m for that row.
• Circling:
  • Uses fixed visibility minima by CAT (A:1.5km, B:1.6km, C:2.4km, D:3.6km).

3. CDFA/Non-CDFA Handling

• CDFA and Non-CDFA conditions toggled by main option and sub-options (CAT A/B only, CAT C/D only).
• Applies correct CDFA RVR caps or no caps/rules per selection and procedure.

4. User Interaction Controls

• Clear All Button:
  • Instantly resets all user inputs, selections, and results for fresh calculation.
• Page Zoom Controls:
  • Fixed top-right bar to zoom the entire tool in/out, improving accessibility.
• Font Zoom Controls:
  • Additional feature to zoom font sizes if configured.

5. Regulatory Status Highlighting

NEW and LATEST (2025-08-16):

• Summary Display: (Located at top/left of summary results section)
  • STANDARD box: Highlighted green if ALL calculated values are standard compliant (at or below required minima).
  • STATE box: Highlighted red if ANY calculated value is a "STATE" value (user input is strictly above required minimum).
• Calculated Value Highlighting:
  • If any result for any row (RVR or VIS) is a STATE value, that specific value is highlighted in red in the summary panel.
  • All other values remain plain/normal—no clutter, no box next to every row.
• Instant, automatic feedback:
  • User immediately sees if any approach has a value over regulatory minimum, at-a-glance.
  • Does NOT change calculation, compliance, or workflow logic—this is for UI visibility only.

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How To Use

1. Open the tool in any modern browser.
2. Select procedure type, category, and lighting as needed.
3. Enter relevant user data (DH, MDH, DA/MDA, RVR/VIS) for each approach.
4. Click “Calculate All”.
5. Review calculated results and regulatory compliance in the summary:
   • STANDARD box green = all values compliant.
   • STATE box red = at least one approach/row uses non-standard minimum; corresponding calculated value appears red.
6. Use Clear All to clear inputs, and zoom buttons to adjust page size for comfort.

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Installation (See Recent update- Use only "index.html" file)

• Copy index.html and calculator.js to your project directory.
• Ensure CSS snippet for state indicators is within or block in your HTML.
• Paste the latest summary logic at the end of calculator.js.
• No other configuration is required.

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Support and Customization

• For additional features, bugfixes, or rule changes, contact Vishal K Basson.
• You can request downloadable bundles, UI tweaks, or workflow improvements at any time.

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CHANGELOG

Latest (2025-08-16):

• Added summary “STANDARD/STATE” highlight logic for instant regulatory status detection.
• Added calculated value highlighting in red for STATE results.
• No per-row box, no workflow clutter—simple, clear summary.
• All other calculation and logic features from previous versions remain.

🚀 Recent Updates (11-2-26)

Single-File Consolidation: Integrated all HTML structure, CSS styling, and JavaScript logic into index.html for maximum compatibility and zero-latency performance.

Dynamic Unit Conversion: Added a real-time toggle to switch between Meter and Feet inputs for DH/MDH, with automatic conversion to the standard 3.28084 ratio.

Enhanced CDFA/Non-CDFA Logic: Automated selection for Non-CDFA rules per Category (A/B or C/D) with forced 5000m RVR rules for MDH exceeding 1200ft.

Precision Floor Logic: Implemented mandatory minimums (250ft for LNAV/VNAV, 200ft for CAT 1) ensuring calculations never dip below safety standards.

📂 File Structure

index.html: The complete application. Contains the CSS grid layout, the RVR lookup arrays, and the calculation event listeners.

⚖️ License

This project is licensed under the GNU General Public License v3.0 (GPL-3.0).

Copyleft: Any derivative work must also be open-source under the same license.

Freedom: You are free to use, modify, and distribute this software.

⚠️ Disclaimer (Experimental Tool)

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND. This is an experiment/demonstration tool only. Calculations provided by this tool are for educational purposes and must NOT be used for actual flight planning or navigation. Always cross-reference results with official charts. The author assumes no liability for errors or consequences resulting from the use of this software.

Created by Vishal Kumar Basson