Module 3 Naval Skills Unit 3 Basic Seamanship

Module 3 – Naval Skills Unit 3 - Basic Seamanship Chapter 3 – Small Boat Seamanship Section 2 – Coxswain

What You Will Learn To Do Demonstrate an understanding of basic care, makeup and use of fiber lines and wire ropes, ground tackle and deck equipment, as it relates to basic seamanship

Objectives 1. Describe the duties of the coxswain 2. Describe the procedures for small boat handling

Objectives 3. Given a set of maneuvering problems related to small craft, use recognized concepts to maneuver a boat in a classroom 4. Describe boat etiquette as practiced by the United States Navy

Key Terms CPS Key Term Questions 1 - 7

Key Terms Coxswain ‑ The person in charge of a small boat Side force ‑ The force that tends to move the boat’s stern sideways in the direction of propeller rotation Screw current ‑ A force on movement of a vessel that is a result of suction current and displacement current

Key Terms Headway ‑ Sternway ‑ Boat etiquette ‑ Pennant ‑ Forward movement; progress in a forward direction The movement of a vessel backward, or stern foremost Customs, honors, and ceremonies related to movement, traffic, and passengers of boats A flag of distinctive form and special significance, displayed on vessels to identify or signal

Opening Question What sort of forces can affect the movement of a boat in water? (Use CPS “Pick a Student” for this question. )

Warm Up Questions CPS Lesson Questions 1 - 2

Coxswain In civilian life, the person in charge of handling a boat is customarily called the boat’s captain. The Navy follows the same tradition.

Coxswain For powerboats, however, the coxswain (pronounced coc'-sun) is the person in charge of the boat, its crew, and any passengers.

Coxswain When a commissioned line officer is embarked as either a boat officer or passenger, this officer may give directions under certain circumstances to the coxswain.

Boat Handling To become a good boathandler, you must understand the forces, controllable or uncontrollable, that act on the boat and cause it to move in one way or another.

Boat Handling Propeller force and rudder pressure are examples of controllable forces. Rudder pressure Propeller force

Boat Handling Uncontrollable forces include wind and current. Current Wind

Boat Handling The interplay of all forces acting simultaneously determines how a boat will respond in a given situation.

Boat Handling Generally, a boat is moved by forces resulting from pressure differences. One such force is propeller thrust. A rotating propeller or screw creates high and low pressure areas on opposite sides of the blades.

Boat Handling A forward movement results when a right-handed propeller rotates clockwise. Stern Thrust High pressure Low pressure

Boat Handling A backward movement results when a right-handed propeller rotates counterclockwise. Stern Thrust Low pressure High pressure

Boat Handling Next in importance is side force, which tends to move the boat’s stern sideways in the direction of propeller rotation. Side force

Boat Handling • Upper blades exert a force opposite to that of the lower blades • Lower blades are moving in water of greater pressure

Boat Handling Single screw ahead Side force Stern tends to starboard Single screw backing Side force Stern tends to port

Boat Handling Side force is greater at lower speeds and when backing.

Boat Handling Screw current has two parts. Suction current flows into the propeller, and is a relatively minor force. Stern Suction current

Boat Handling Discharge current flows away from the propeller, and is a major force in going forward and backing. Stern Discharge current Suction current

Boat Handling With the screw going ahead, discharge current is strong on the rudder. Forward Ru dd er Discharge current Side force (view from below)

Boat Handling When backing, discharge current against the boat’s hull is a strong side force. Ru dd er Forward Discharge current Side force (view from below)

Boat Handling Screw (ahead) Discharge current

Boat Handling Single Screw Twin Screw A twin-screw ship or boat usually has a rudder behind each propeller, as shown, but could have a single rudder between the two propellers.

Check On Learning Questions CPS Lesson Questions 3 - 4

Boat Handling A rudder is used to attain or maintain a desired heading. Controlling forces and compensating for uncontrollable forces guide the stern.

Boat Handling Rudder effect depends on: • Rudder size, angle, and location • Boat speed • Direction of propeller rotation • Headway (ahead) and sternway (backing) • Suction and discharge currents • Side force

Boat Handling • Rudder size, angle, and location • Boat speed • Direction of propeller rotation • Headway (ahead) and sternway (backing) • Suction and discharge currents • Side force = Resultant force The direction and amount of net force exerted on a boat’s stern.

Boat Handling A single-screw boat or ship has a tendency to back to port, effected by four distinct forces. Discharge current from the propeller Starboard Suction current from propeller drawing water from astern Port Normal steering effect of the rudder Sidewise pressure of the blades

Boat Handling 1. Discharge current from the propeller 2. Suction current from propeller drawing water from astern 3. Sidewise pressure of the blades 4. Normal steering effect of the rudder How do these four forces impact the movement of the boat? In the situations that follow, assume there is no wind, tide, or current, unless specifically stated.

Boat Handling Boat going ahead from standstill, right rudder on: • Screw starts turning over • Screw hits rudder and forces stern to port Right rudder on

Boat Handling Boat proceeding ahead, left rudder on: • Stern moves to starboard • As speed picks up, the effect of the screw current diminishes • Normal steering effect controls the heading Left rudder on

Boat Handling As the boat proceeds ahead, a change in the rudder direction requires about two or three boat lengths before achieving the desired effect—a little faster at higher speeds. Because there is a brief adjustment, the operator may not be able to avoid a collision with a quick turn.

Boat Handling When backing, the effect of the forces on rudder hard right are: Discharge current Suction current (weaker at first) Side force Steering effect

Boat Handling When backing, the effect of the forces on rudder hard left are: Steering Discharge current effect Suction current (weaker at first) Side force

Boat Handling Relationship of discharge current to speed when boat and screw are going ahead Discharge current Highest Lowest Speed Highest

Boat Handling When backing over longer distances, it is usually necessary to reverse the rotation of the screw and shift the rudder long enough to straighten out the boat.

Boat Handling Strong winds affect backing ships and boats. Until you discover differently, assume a boat will more easily land to port.

Boat Handling When trying to avoid danger ahead with screw backing remember that direction changes entail adjustment. Continued forward motion turn to starboard 3 4 2 1 Danger ahead Reverse screw hard right rudder Boat backing rudder in charge

Check On Learning Questions CPS Lesson Questions 5 - 6

Making a Landing It’s good advice to make a landing heading into the wind, if possible, or to make it on the side of the pier where wind or current will work in your favor. However, such choices are usually not an option.

Making a Landing A good coxswain learns to adjust to any circumstance and handle the boat correctly in an almost secondnature manner.

Making a Landing In the examples that follow, it is assumed the boat handler understands: • The boat’s typical response to speed and direction variations • How far the boat will fetch (glide) with the screw in neutral

Making a Landing When bow line is secured to pier left rudder commence backing Bow line 20° to 30° angle Port-side-to landing

Making a Landing When the bow line is secured to pier right rudder commence backing. Bow line 20° to 30° angle Starboard-side-to landing

Making a Landing Making use of current… Current On pier Current Off pier

Twin-Screw Boats Port propeller counterclockwise Starboard propeller clockwise Boat going ahead Port propeller clockwise Starboard propeller counterclockwise Boat going astern

Twin-Screw Boats When the bow line is secured to pier port engine back, starboard engine ahead, left rudder. Bow line Maneuvering a twinscrew craft into a pier

Twin-Screw Boats Port engine ahead, starboard engine back, right rudder, when clear of pier, port engine back, rudder amidships and maneuver to safe waters. Maneuvering a twin-screw craft away from a pier

Boat Etiquette Boat etiquette traditions have been passed along since the founding of the Navy. Observance of proper boat etiquette is second in importance only to safety aspects of boat handling. Adm. Jonathan Greenert Chief of Naval Operations (CNO) renders honors to the national ensign

Boat Etiquette Boat etiquette consists of: • Customs • Honors • Ceremonies

Boat Etiquette Established customs to promote boat etiquette involve: • Landing of passengers • Governing boat traffic • Expediting movement of boats at gangways and piers

Boat Etiquette Clean boats and sharp, courteous crews are signs of good seamanship and make a lasting impression.

Boat Etiquette Hand salutes are rendered to boats carrying officers and officials in much the same way as while walking on land.

Boat Etiquette It is not the size or type of boat, but the rank of the officer aboard that determines a boat’s seniority. If you can’t determine rank, offer the first salute.

Boat Etiquette Boat salutes are rendered by a boat’s coxswain and by the senior officer embarked.

Boat Etiquette During a salute: • The engine of the junior boat should be idled; it can resume after the salute is returned • Coxswains rise unless it is dangerous or impractical • Officers generally do not rise to salute

Boat Etiquette During morning or evening colors, a boat’s engine should be idled or stopped and the clutch disengaged. The boat officer and coxswain stand at attention and salute in the direction of the ceremony, if it is possible to do so without losing control of the boat.

Boat Etiquette The coxswain in charge of a boat salutes when officers enter or leave the boat if the situation allows.

Boat Etiquette Make way for seniors quickly, quietly, and without confusion.

Boat Etiquette Courtesy aboard boats: • Juniors board first and leave after seniors • Seniors take the seats farthest aft

Boat Etiquette At sea, as long as safety is not compromised, junior boats must avoid embarrassing senior boats. At landings and gangways, juniors should give way to seniors.

Boat Etiquette Juniors defer to seniors by not crossing the bows of their boats or ignoring their presence. Normally, enlisted personnel remain silent in boats with officers aboard.

Boat Etiquette The national ensign is displayed from boats of the Navy when: • Under way during daylight in a foreign port • Dress or full dress occasions • Going alongside a foreign vessel • Officers or officials are embarked on official occasions

Boat Etiquette • When a flag or general officer, a unit commander, a commanding officer, or a chief of staff is embarked in a boat of his or her command or in one assigned for personal use • At times prescribed by the senior officer present

Boat Etiquette On official occasions, an officer in command, or a chief of staff acting for an officer in command, displays a personal flag or command pennant from the bow. If not entitled to either, a commission pennant is displayed. Broad command pennant Commission pennant

Boat Etiquette Admiral Rear Admiral (Upper) Vice Admiral Rear Admiral (Lower)

Review Question What are the reasons for setting forth standards for boat etiquette? (Use CPS “Pick a Student” for this question. )

Closing Questions CPS Lesson Questions 7 - 8

Questions?