🔍 Key Concepts

• Rule 27 – Vessels Not Under Command or Restricted in Their Ability to Maneuver (Navigation Rules) • Day shapes for vessels engaged in underwater operations • Special signals for diving operations on small vessels when normal shapes are impracticable

💭 Think About

• Which of these options is associated with diving in both day and night signals, especially for small craft? • Which shapes (balls, cylinders) are normally used for restricted in ability to maneuver or vessels at anchor, and do they specifically indicate divers in the water? • Think about what signal a recreational dive boat would use to warn other vessels to keep clear, and how that’s represented in the Rules.

✅ Before You Answer

• Identify which option is specifically tied to divers in the water in the Navigation Rules, not just any restricted‑maneuvering vessel. • Eliminate any shapes that are standard day shapes for other conditions (e.g., constrained by draft, restricted in ability to maneuver, at anchor). • Confirm that the correct signal is acceptable by day for a small vessel when the usual underwater-operations shapes cannot be shown.