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Course # Module 1
Principles of Small Craft Naval Architecture
Course # Module 1 Objectives
Describe the design spiral
Comprehend and discuss the basic laws of flotation and describe the basic physical laws which state how various propulsion systems work.
Solve basic algebraic, geometric, and trigonometric problems after completing this math review.
Discuss the meaning of a set of hull lines, calculate displacement using Simpsons Rule or the Trapezoidal Rule, locate the center of buoyancy of a hull, and compute wetted surface, and perform a weight study and locate a hull’s center of gravity.
Discuss and apply the concepts involved regarding the nature of frictional, residual and wind resistance and be able to make recommendations to reduce resistance. Calculate righting arms and righting moments at any angle of heel, analyze stability curves, and comprehend the principles of trim and flotation.
Create and prepare presentation drawings and proposals for new yachts.
Use the required drafting instruments to properly draw lines, curves fair sweeps and other figures needed to draw working plans and apply what you have learned to draw an outboard-profile elevation and general-arrangement plan.
Create and draw and fair a complete set of hull lines, prepare a table of offsets, and a set of hydrostatic calculations for a hull lines drawing.
Obtain a passing grade on a series of written examinations demonstrating that the student attained the required knowledge in the subjects presented in this course and can apply the knowledge to correctly answer the questions and problems presented in the examinations. .
Course # Module 1 Goals
The overarching goals of this course are to enable students to:
Analyze the meaning of a set of hull lines and to calculate the various physical characteristics that describe a boat.
Discuss and break down the nature of frictional and residual resistance and be able to make recommendations to reduce resistance.
Describe the mechanisms involved in transverse metacentric stability and dynamic stability and acquire a comprehension of the principles trim and flotation.
Develop the skills required for manual marine drafting.
Draw and fair a complete set of hull lines
Obtain a passing grade on a series of written examinations demonstrating that the student attained the required knowledge in the subjects presented in this course and can apply it to correctly answering exam questions and problems
This course prepares the student to work as an apprentice to yacht and boat designers with production boat building companies or at firms engaged in private practice while continuing his/her studies. It is the prerequisite to course # Module 2.
Employ a segment of the design spiral to solve a typical design office problem.
Explore several alternatives in order to arrive at the best solution.
Present best solution graphically in the form of a preliminary sketch.
LESSON 8: Stability 2 - Longitudinal Stability
Trim and Flotation
a. Change in level flotation
b. Immersion Calculations
Longitudinal Stability
a. Longitudinal GM
b. Longitudinal Moment of Inertia of Waterplane
Calculations for Change of Trim
a. Moment to trim 1 inch (or 1 centimeter)
b. Correcting out of trim conditions
Design Considerations
a. Variable Loads
b. Comfort Zones
c. Roll Period
Dynamics
a. Pitching
b. Heel and Trim in Sailboats
c. Pitchpoling, Chine Walking, Porpoising
d. Trim Tabs
LESSON 9: Review
Topics lessons 1 thru 8 as needed to clarify concepts or methods
LESSON 10: Introduction To Marine Drafting
Design/Graphics/Communication
a. The design Process Revisited
b. Where do ideas come from?
c. Level 2, 2, 3, and 4 design phases
d. Sketching
Drawing Instruments and Media
a. Equipment and Materials List for Manual Drafting
b. Drafting Tables
c. Pencils and leads
d. Media
e. Scales and Planimeters
f. Ships Curves, splines, and Spline Weights
Layout of Sheets and Scales
Lettering
Practical Exercises
Computer Aided Drafting
LESSON 11: Drawing Of Hull Lines
The meaning of a Set of Lines
Relative Importance of Various Lines
V-Bottom hulls
Round Bottom Hulls
Layout
Drawing the Designed Waterline
Sketching in the Section Lines
Purpose of Diagonals
Buttocks
The Fairing Process
The Offset Table
Parallel Buttock Principle
Form and Proportion
A working Procedure for Drawing a Set of Lines
Hull Line Examples
a. Contemporary High Speed Deep-V planing hull
b. 42’ Medium Displacement Sailing Yacht
c. 43’ Sportfisherman
d. 22’ Contemporary V-Bottom Runabout
e. 13.7m IMS Cruiser/Racer