Question 36 RVR03 - Mate of LT 500-1600 GRT

The Correct Answer is A. **Explanation for A (about 1 second):** Option A is correct because it accurately describes the duration of a "short blast" of the whistle, as defined by both the International Regulations for Preventing Collisions at Sea (COLREGs) and the Inland Rules (33 CFR 83). The maneuvering and warning signals used in head-on and/or crossing situations (such as one short blast for "I am altering my course to starboard," two short blasts for "I am altering my course to port," and three short blasts for "I am operating astern propulsion") all utilize the short blast signal. A **short blast** is defined as a blast of about one second's duration. **Explanation for Incorrect Options:** * **B) 2 to 4 seconds:** This duration is too long for a short blast. While a long blast (defined as 4 to 6 seconds) is used for warning signals, leaving a dock, or restricted visibility signals, it is never used for the maneuvering signals required in head-on or crossing situations. * **C) 4 to 6 seconds:** This range defines a **prolonged blast** (or long blast). Prolonged blasts are used for signals like restricted visibility (Rule 35) or when leaving a berth (Rule 34(d)), but not for the specific maneuvering signals (one, two, or three blasts) utilized during head-on or crossing encounters. * **D) 8 to 10 seconds:** This duration is excessively long and does not correspond to any standard, defined whistle signal (short, prolonged, or repeated blasts) under COLREGs or Inland Rules.