Design Articles

See also: Boatbuilding Articles

FOAM CORE MATERIALS IN THE MARINE INDUSTRY
APRIL 2002

DIAB, Inc.

For over 60 years foam cores have been utilized in marine applications to lighten, stiffen, and strengthen everything form hull bottoms to fly bridges. But what exactly is foam core? What type do I use, and where can I use it? Should I use it instead of balsa or plywood? With the seemingly endless variety of foam core materials on the market today, it can be frustrating for the average boating enthusiast to find the right foam core for his/her particular application. This article will attempt to inform boat builders about the properties and correct manufacturing procedures involved in constructing foam core sandwich laminates.

FOAM CORE MATERIALS IN THE MARINE INDUSTRY CLICK HERE TO READ THE FULL ARTICLE

HISTORY OF SAILING YACHT MASTS, RIGGING, AND SAILS: 1900-PRESENT DAY
MARCH 2002

James Gilliam

The design, construction and materials of masts, rigging and sails have changed greatly over the course of the 20th century. From solid wooden masts built from a single tree to carbon fibre sections aerodynamically tested, super light and super strong. For sails there have been developments from natural materials such as cotton, which had a tendency to rot and stretch when wet, to new materials such as North sails 3DL sails using Vectran, carbon fibre, Kevlar and exotic films and glues.

HISTORY OF SAILING YACHT MASTS, RIGGING, AND SAILS: 1900-PRESENT DAY CLICK HERE TO READ THE FULL ARTICLE

WHAT MAKES THE TUNNEL HULL WORK?
FEBRUARY 2002

AeroMarine Research

A three-part article written by Jim Russell of AeroMarine Research which summarizes the main factors involved in tunnel boat design.  Jim has written a number of books including Secrets of Tunnel Boat Design and History of Tunnel Boat Design and has also created the Tunnel Boat Design Program software. Hopefully you will find this three-part article to be an interesting introduction to the hydrodynamic and aerodynamic forces which must be carefully considered and skillfully balanced in the design of a high performance powerboat.  For designers not already familiar with the intricacies of tunnel boat design, this article will provide a good starting point and will hopefully spark your interest.  And I believe the more advanced designers among our audience will find this series of articles to be a great preview of the Books and Software from AeroMarine Research which continue to take tunnel boat and aerodynamic design much further.

Part I provides an overview and discusses Lift.  Part II describes the Drag = Thrust relationship.  Part III looks at the necessary dynamic balance of forces.

	WHAT MAKES THE TUNNEL HULL WORK? PART I - LIFT AND WEIGHT CLICK HERE TO READ THE FULL ARTICLE
	WHAT MAKES THE TUNNEL HULL WORK? PART II  - DRAG AND THRUST CLICK HERE TO READ THE FULL ARTICLE
	WHAT MAKES THE TUNNEL HULL WORK? PART III - DYNAMIC FORCE BALANCES CLICK HERE TO READ THE FULL ARTICLE

REVISITING A MAST-AFT SAILING RIG
MARCH 2001

RunningTideYachts, Ltd.

A fascinating article from Brian Eiland detailing his development of a sailing rig which discards the "inefficient mainsail, and replaces it with two clean leading-edge headsails, acting in a parallel, harmonious fashion" with a mizzen sail creatively added and the mast stepped aft in the cockpit area and canted forward 10 degrees.

This design provides:

1.)	A cruising rig that is more aerodynamically efficient.
2.)	A rig that delivers a clean leading edge for all the sails
3.)	A rig that allows the whole sail plan to be roller-furled away or deployed.
4.)	A rig that allows the reefing of the sails without turning into the weather.
5.)	A rig that divides up the total sail area into smaller manageable sizes.
6.)	A rig that maintains its balance center (CE) with different sail combinations.
7.)	A rig that produces less overturning moments.
8.)	A rig that can be operated without leaving the cockpit.

We believe that you will find both the developmental narrative and the concept extremely interesting.

REVISITING A MAST-AFT SAILING RIG CLICK HERE TO READ THE FULL ARTICLE