THE DEVELOPMENT OF THE FAT PENGUIN - A Foil
By Paul Cole - Designer

Introduction

I'm the designer of the Fat Penguin - Integrated Flow Form. The Fat Penguin is a new approach to surf craft design; a way of moving to a new level based on scientific principles and solid research into many related technologies. I have been building surfboards since I was 14 years old and am now 49. I got my first surfboard when I was seven; it was an 11'4" Ron Triple 3/4" Stringer and a D-Fin. I grew up at Cronulla Point and became a shaper for G&S.

I left pro-style surfing world in 1974 to go motorcycle racing but I still surfed. My main skills are Flow Dynamics dealing with gases and fluids. In 1988 I started work on the combining surfboard design with applied science and the latest technology.

There are 36 Fat Penguins now in existence. To get to the present level of development has taken 12 years of R&D and a lot of work. This article describes what went into their development.

Background

According to Archimedes, the force a fluid can exert on an object is proportional to it's surface area. The current surfboard is technically a PLANING surf-form. Michael Paine (B.Eng.) wrote a thesis on how the current surfboard works. The current thruster short-board is a very refined product that is now in a steady state as far as advancement of surf craft is concerned.

To develop a new improved approach to surf craft design, I used research information assembled from the fastest flow forms on the planet. I consolidated the profiles of aircraft including Mig foxbat, F-16, SR 71 blackbird, J-39 Euro jet. I next added profiles from the fastest bullet, Mako shark, Spanish mackerel, Tuna; Penguins and finally 12 metre racing yachts. After two and a half years of assembling and crunching data a commonality of flow forms emerged.

Knowing the surf industry would resist anything new I set up controlled test sessions using a series of 21 test boards. The Fat Penguin has 7 subsections that are assembled to create a lifting bodyform. Each of the seven sections needed to be checked and refined. It took 17 months to check and refine the fin system alone. The first 9 test boards gave my research solid direction for the shape. By test board 21, the shape was working well, but tuning in the fins to prevent drag wasn't perfected until No. 26, which was a beautiful board to ride.

The Physics of the Fat Penguin

The hard science used to evolve the FP project is the same as NASA and Japanese Aerospace Engineers used in designing the space shuttle and NASP pressure wave gliders. There is also a mathematical formula to describe the flow shape that took over two years to assemble using the theories of Archimedes, Newton, Freude, Reynolds, Chung, Burt, Rutan, and Helmholtz. This was a big headache to get through yet it was vitally important that the core theory of making the project sound.

When Simon Anderson introduced the thruster fin system in 1976, it revolutionized the way surf craft would plane. The Fat Penguin is an Aquatic Glider with far higher lift/drag ratios then planning gliders, making it more efficient. An analogy would be a paper kite compared to a glider.

What is an Integrated Flow Form?

Answer- The Fat Penguin is comprised of subsections.

(1) NOSE
(2) TAIL
(3) BOTTOM
(4) DECK
(5) WINGS
(6) RAIL LINE
(7) FINS

NOSE

The nose is like a big wave speed board built to drive, great for late take-offs. It has a low area high speed profile that smoothes out chop and has the ability to really attack a wave

TAIL

Slightly rounded 5"to 6" Square tail chosen for stability and to give a straighter and faster rear rail line with small enough surface area enabling high speed cutbacks. The tail works well high in a wave and suits vertical maneuvers.

BOTTOM

The concave provides lift. You cannot compress a liquid so it accelerates. By the time it reaches the tip of the concave the fluid is moving faster than the fluid at the edge of the board. The concave tip shape is very important; it directs the accelerated fluid flow to the sudden tail lift. The sudden tail lift at the end of the concave running into the back of the board encourages the rear stern pressure waves to return early under the tail of the board, creating a high pressure zone under the tail. This recycles energy rather than throwing it away as spray. Water flows from a larger area to a smaller surface area and into the tail quickly - great for snap turns. The vee bottom was added for stability, cutbacks and tight hard turns. Work on stern pressure waves was based on Professor Dubeur.

DECK

The deck draws on "Bernoulliís principles" to create a narrow waist to encourage the fluid flow to hug the body form e.g. Spitster boatail bullet, SR.71 Blackbird, Migs, f16.

WINGS

The wings are called pectoral flyers. They add stability and lift when trimming or driving and their effect is very noticeable in white water.

- to provide surface area and lift at low speed.
- to create a rear section Rail line of a modern short board 19.5" wide
- for change of rocker. In full rail bottom turns you use the full rocker for big arcs. The wings at speed are neutral stabilizers you wouldn't know they were there. For short radius turns the change in rocker makes this easy. Check out a photo of surfers doing cutbacks or tight top slashes. They are only using the back half of their boards. The wing chord profiles a copy of a mach 2.5 low form.

RAIL LINE

The rail line is hard and low at the nose and progressively softens to the boardís widest point; the back one third of the rail is hard and low.

FINS

There are two sets of fins on the FP. The front set are called VENTRAL FINS and are there to stop yawing at high speed and in a tight turn they act like a Carnard wing helping steer the board round them. The rear fins are a set of twin fins about the size of a single fin with the base area cut away to make them loose at low speeds. The third thruster fin was made redundant by the pintail concave and tail relief.

THE TEST RIDERS

Several test riders have taken the board for a few days or weeks in exchange for feedback. As for Pro-surfers, yes there have been a few. Pros can't really endorse a different design as they risk loosing sponsorship. Encouragement and feedback has been received from long-term surfers who knew their sport and who were open minded enough to try something new.

Fat Penguin 2000
Web page: www.spacegroove.com/fatpenguin/
E-mail: fatpenguin2000@hotmail.com