For single runway designators, which feature makes the red color more conspicuous on the extremity runway designation sign?

For single runway designators, which feature makes the red color more conspicuous on the extremity runway designation sign?

• A. Increased width
• B. Decreased width
• C. Extra sign height
• D. Different color

Answer: (A)

Conspicuity at distance comes from how large the colored area appears to the pilot. For an extremity runway designation sign on a single runway, widening the sign increases the red field that pilots scan, which makes the sign stand out more quickly as you approach from the air or on the ground. The larger red area raises the sign’s angular size in the pilot’s view, improving recognition and reducing search time, especially against complex backgrounds or in varying lighting. The color is fixed as red in this context, so simply changing color isn’t the mechanism for increased visibility. A taller sign could help somewhat, but width has the bigger impact on how conspicuous the red is from a distance.

Conspicuity at distance comes from how large the colored area appears to the pilot. For an extremity runway designation sign on a single runway, widening the sign increases the red field that pilots scan, which makes the sign stand out more quickly as you approach from the air or on the ground. The larger red area raises the sign’s angular size in the pilot’s view, improving recognition and reducing search time, especially against complex backgrounds or in varying lighting. The color is fixed as red in this context, so simply changing color isn’t the mechanism for increased visibility. A taller sign could help somewhat, but width has the bigger impact on how conspicuous the red is from a distance.