Geo

Geographic Data Validator

Systematic validation of geographic data in aviation/travel applications.

Audit Process

Run each validation category. Flag every error. Score each category 0-10.

Category 1: IATA Airport Code Validation

Checks

• Code format: All IATA codes are exactly 3 uppercase letters.
• Code existence: Every code maps to a real, operational airport.
• Code currency: No closed/decommissioned airports (e.g., TXL closed 2020).
• Multi-airport cities: Correct airport chosen for the city.
  • Berlin: BER (not TXL or SXF, both closed)
  • London: LHR (Heathrow), LGW (Gatwick), STN (Stansted), LTN (Luton), LCY (City)
  • New York: JFK (Kennedy), EWR (Newark), LGA (LaGuardia)
  • Tokyo: NRT (Narita), HND (Haneda)
  • Paris: CDG (Charles de Gaulle), ORY (Orly)
  • Istanbul: IST (Istanbul Airport, not SAW which is Sabiha Gokcen)
  • Mumbai: BOM (not MUM)
  • Rome: FCO (Fiumicino, not CIA Ciampino for international)
• Primary airport: For programmatic pages, use the PRIMARY international airport.

Common IATA Mistakes

Category 2: City Name Accuracy

Checks

• English names: Using standard English city names (not local names in English context).
  • Mumbai (not Bombay), Beijing (not Peking), Kolkata (not Calcutta)
  • BUT: standard English names where established (Munich not Munchen, Rome not Roma)
• German names: Using standard German city names in DE context.
  • Munchen (not Munich), Rom (not Rome), Lissabon (not Lisbon)
  • BUT: keep English for international cities (New York, not Neuyork)
• Slug consistency: Slugs use English city names regardless of locale.
  • munich-to-istanbul (not muenchen-nach-istanbul)
• City-airport alignment: City name matches the airport's actual city.
  • FRA is in Frankfurt (correct), not "Frankfurt am Main" in slugs
  • NRT is Narita but city should be "Tokyo" (that's where travelers mean)
  • FCO is Fiumicino but city should be "Rome"
  • ORY is Orly but city should be "Paris"
  • LHR is Heathrow but city should be "London"

Slug Generation Rules

lowercase(english_city_name_origin) + "-to-" + lowercase(english_city_name_destination)

Use the CITY name, not the airport name. "hamburg-to-london" not "hamburg-to-heathrow".

Category 3: Country Code Validation (ISO 3166-1 Alpha-2)

Checks

• Format: All country codes are exactly 2 uppercase letters.
• Existence: Every code is a valid ISO 3166-1 alpha-2 code.
• Currency: Using current codes (not historical).
• Geopolitical sensitivity: Correct handling of disputed territories.
  • Taiwan: TW (ISO standard, but some APIs use CN)
  • Kosovo: XK (not ISO standard but widely used)
  • Palestine: PS
  • Hong Kong: HK (not CN)
  • Macau: MO (not CN)

Flag URL Validation (flagcdn.com)

https://flagcdn.com/{width}x{height}/{lowercase_country_code}.png

• Country code MUST be lowercase in URL: de not DE
• Standard sizes: 16x12, 20x15, 24x18, 28x21, 32x24, 40x30, 48x36, 56x42, 64x48, 80x60
• Retina: use 2x size in srcSet (e.g., 40x30 base, 80x60 2x)
• Some codes don't have flags on flagcdn (e.g., XK for Kosovo)

Category 4: Flight Distance & Time Estimates

Checks

• Great-circle distance: Within 5% of actual great-circle distance between airports.
• Flight time formula: distance_km / 850 + 0.5 hours (850 km/h avg cruise + 30min taxi/climb/descend).
• Reasonableness check: Flight times match reality within 15%.

Reference Distances (verify against these)

Stops Classification

Flags

• Flight time < 45 min: verify route exists (too short for commercial)
• Flight time > 18 hours: verify this is a real route (may need 1+ stops)
• Distance > 15,000 km: almost certainly requires a stop

Category 5: Route Feasibility

Checks

• Route actually exists: Airlines operate scheduled service on this route (direct or common 1-stop).
• Seasonal routes: Flag routes that are seasonal only (e.g., summer charters).
• Hub logic: Origin-destination pairing makes geographic sense.
  • FRA-DEL: Yes (Lufthansa hub to major Indian city)
  • HAM-NRT: Questionable (no direct, would connect via FRA/MUC)
• Airline availability: Named airlines actually fly this route.
• Directional logic: For reverse routes, verify demand exists (diaspora corridors, business travel).

German Hub Routes (verified operational)

Category 6: Geopolitical Accuracy

Checks

• Conflict zone alignment: Routes flagged as "near conflict zone" actually pass near that zone.
  • BER-IST: Passes near Black Sea / Ukraine zone (correct)
  • FRA-DEL: Passes near Iran/Pakistan airspace (correct)
  • FRA-BKK: Overflies Iran or detours south (correct to flag)
  • BER-LHR: Does NOT pass near any conflict zone (correct to not flag)
• Safety level accuracy: Zone risk levels match current data.
• Country name sensitivity: Using internationally recognized names.
  • "Turkiye" (official) vs "Turkey" (common English): use "Turkey" in English context
  • "Myanmar" (official) vs "Burma": use "Myanmar"
• Airspace routing: Commercial flights may not fly the great-circle route due to airspace restrictions. Flagging conflict zones should consider actual likely routing, not just great-circle proximity.

Scoring

Passing score: 9/10 overall. Geographic errors in production are factual errors that destroy user trust.

Quick Audit Command

When invoked as /geo, validate all geographic data in the current plan or code. Check every IATA code, city name, distance, flight time, and route feasibility. Output the scoring table with specific errors found.

Data Sources for Verification

• Airport codes: IATA official list, airportcodes.io, Wikipedia "List of airports by IATA code"
• Distances: Great Circle Mapper (gcmap.com), or calculate from coordinates using Haversine formula
• Flight times: Google Flights actual results, airline schedules
• Country codes: ISO 3166-1, restcountries.com API
• Conflict zones: EUROCONTROL NOTAMs