What color and shape define a mandatory instruction sign on the airfield?

What color and shape define a mandatory instruction sign on the airfield?

• A. Blue background with white lettering
• B. Red background with white lettering
• C. Yellow background with black lettering
• D. Green background with white lettering

Answer: (B)

Mandatory instruction signs on the airfield use a red background with white lettering. This color combination instantly signals actions that must be followed, such as stops or holds, and the white letters ensure the message is easy to read from a distance. These signs are typically rectangular and placed at points where compliance is required to safely proceed, like near hold-short lines or runway entrances. Other sign types use different color schemes, so the red-with-white-inscription combination uniquely identifies a mandatory instruction.

Mandatory instruction signs on the airfield use a red background with white lettering. This color combination instantly signals actions that must be followed, such as stops or holds, and the white letters ensure the message is easy to read from a distance. These signs are typically rectangular and placed at points where compliance is required to safely proceed, like near hold-short lines or runway entrances. Other sign types use different color schemes, so the red-with-white-inscription combination uniquely identifies a mandatory instruction.