Sight distance for landing – assumed pilot’s eye height For approach and runway sight-distance calculations, what standard height above the runway surface is the pilot’s eye commonly assumed to be?
-
A1 m
-
B3 m
-
C4 m
-
D5 m
-
E2 m
Answer
Correct Answer: 3 m
Explanation
Introduction / Context:Several runway and approach visibility computations, including approach lighting and decision cues, use a conventional pilot’s eye height to standardize sight-distance assessments across aircraft types.
Given Data / Assumptions:
- Standardized planning assumptions for approach and landing.
- Representative jet transport cockpit heights relative to runway surface.
Concept / Approach:Using a single height simplifies calculations and ensures conservative, reproducible results. A value around 3 m approximates the eye position of flight crew in many transport category aircraft during flare/touchdown phases, and is widely adopted for geometric checks.
Step-by-Step Solution:Identify the standard convention needed for sight-distance geometry.Adopt the commonly used pilot’s eye height for approach calculations: 3 m.Select 3 m as the correct option.
Verification / Alternative check:Design guides and exam keys frequently cite 3 m as the nominal eye height for runway visibility envelopes.
Why Other Options Are Wrong:
- 1 m / 2 m: Too low for transport-class cockpits, not conservative.
- 4 m / 5 m: Higher than standard convention; could over-predict visibility.
Common Pitfalls:Confusing antenna height, gear strut length, or tail height with the pilot eye reference used in visibility checks.
Final Answer:3 m