Side-by-Side Comparison
Airport Runways & Infrastructure
PAPI & VASI Lighting vs. Runway & Taxiway Lighting
Comparing 2 standards across 10 specifications. 10 key differences identified.
Comparing:
PAPI & VASI Lighting
Runway & Taxiway Lighting
The Precision Approach Path Indicator (PAPI) and Visual Approach Slope Indicator (VASI) provide visual glide slope guidance on final approach using color-transition optical lenses: 4 White (Too High), 2 Red / 2 White (On 3.0° Slope), and 4 Red (Too Low).
Airfield lighting follows strict international color codes to prevent runway incursions: Runway Edge (White / Amber), Runway Threshold (Green), Runway End (Red), Taxiway Edge (Blue), and Taxiway Centerline (Green).
Specification Comparison Table
10 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard Approach Angle
|
3.0 degrees standard (up to 5.5° on steep approaches like London City EGLC) | — |
|
PAPI Array Layout
|
Single row of 4 light units perpendicular to runway on left side | — |
|
VASI Array Layout
|
2 or 3 bars of lights in tandem (Upwind / Downwind bars) | — |
|
Visible Range
|
5 miles (8 km) by day, up to 20 miles (32 km) at night | — |
|
Standard Authority
|
— | ICAO Annex 14 / FAA AC 150/5340-30 |
|
Runway Edge Lights
|
— | White (transitions to Amber on final 2,000 ft or half of runway) |
|
Threshold Lights
|
— | Unidirectional Green indicating landing threshold |
|
Runway End Lights
|
— | Unidirectional Red indicating physical end of pavement |
|
Taxiway Edge Lights
|
— | Omnidirectional Blue |
|
Taxiway Centerline
|
— | In-pavement Green (alternating Green/Amber in runway lead-on/off zones) |