Which statement best describes the layers of a modern ship's air-defense envelope and how they cooperate?

• A. Only a single-layer system is used to simplify maintenance.
• B. Early warning sensors and C2; point-defense systems (CIWS); short-range missiles; decoys and EW measures; layered integration provides overlap and redundancy.
• C. Decoys alone provide complete protection.
• D. Passive camouflage replaces the need for active sensors.

Answer: (B)

Modern ships depend on a multi-layer air-defense envelope where detection, decision-making, and engagement happen across several overlapping ranges to create redundancy and maximize protection. Early warning sensors and the command-and-control network provide the initial picture: they detect and track incoming threats at long range, classify them, and cue the rest of the system. The point-defense suite, such as a close-in weapon system, sits at the innermost layer to quickly defeat threats that break through earlier defenses with rapid-fire capability and immediate response. Between these extremes, short-range missiles offer an intermediate layer of intercept capability, catching threats that are closer but still outside the close-in field of fire. Decoys and electronic warfare measures add probabilistic protection by confusing or misleading guidance systems, reducing the likelihood a threat can stay on a correct track to the ship. All of this is tied together by layered integration, meaning data fusion and coordinated engagement so that the right weapon fires at the right time and the system can adapt if one layer is degraded or overwhelmed. This overlap and redundancy make the defense much more effective than any single layer could be.