Aerodrome Supplementary Guidance: Declared Distances, Lighting Reference, and Sign Colors
Summary of Declared Distances
| Distance | Definition | Formula (Simplified) |
|---|---|---|
| TORA | Take-Off Run Available | Physical runway suitable for takeoff roll |
| TODA | Take-Off Distance Available | TORA + Clearway (CWY) |
| ASDA | Accelerate-Stop Distance Available | TORA + Stopway (STW) |
| LDA | Landing Distance Available | Runway available for landing (affected by displaced threshold) |
- TODA includes the Clearway (may be over water).
- ASDA includes the Stopway (load-bearing pavement for emergency braking).
- If no Stopway, no Clearway, and no displaced threshold: TORA = TODA = ASDA = LDA.
Approach Lighting
Approach lighting measurement is always taken from the threshold outwards.
Sign Colors (Summary)
- Mandatory Instruction Signs: White on Red (e.g., STOP, NO ENTRY).
- Location Signs: Yellow on Black.
- Direction/Destination Signs: Black on Yellow.