Typical Styles of Bow Sections & Hulls

MODEL - MODIFIED - SPOONBILL & SCOW = BOW'S

     All shipbuilders have particular styles, traits and characteristics, setting them apart.    So you can study a particular shipyards work and instantly see their characteristics after some study.    But remember, all shipyards can marry ( join together ), virtually any style of "Bow Design", to the rest of a hull, to suit whatever a buyer wants.    This means a hull basically consists of Three - Sections = Bow / Mid-ship & Stern and each can be built in various styles and shapes.    Yet married together with only a few changes made, to accomplish the job.    Here shipyard traits are usually easily recognized, once you understand the shipbuilders style and how they do things.   "Basically its like the difference between "Fords & Chevy's!" ... After a while you can easily spot and tell the difference at glance.

     Whether an entire vessel, or just structures and they're shapes, buyer's often want something different from a builder's norms.    REMEMBER .... Things sometimes can be puzzling, but the overall look of a vessel usually shows traits of who built it if you study the design closely.    Today, thanks to computer 3-D drafting & design software, high tech construction methods can build structures at one shipyard, while another shipyard someplace else, builds the hull or other sections.    Then they simply bring all the parts together, using heavy lift -cranes, which is called "Modular Pre-fabrication" and weld them together.    Its commonplace at many shipyards - today, as well as faster and it reduces costs.    But also insures everything fits perfectly upon assembly is done, right down to where the wiring goes.    Here, everything within each section, must be pre-installed in order to make the modular system of building - work.

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    A "MODEL" BOW = Can be used on any size or type of hull, no matter its width or drafts and lengths.    However, its Deep - V shape, is not always continued further back into the hull's = mid-ships or stern sections.    Why? .... Because a V- shaped hull, to easily tips over, if the hull goes aground and it would most likely = roll-over & sink.    Model Bows are generally married into a more typical - Flat Bottom style of Mid - Hull Section.    Or this type of bow section can be used on vessels designed to work only in certain areas, where its deeper v- drafts won't be effected by dangers of running aground.    And this is a favored style of towboat hull designs, for Southern Gulf - Shipyards.    Such Gulf shipyards produce what is commonly called a "Cajun Towboat", for their unique styles, which use traits from Tugboats - as a concept to create a combination Tug & River Workboat.

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    THE MODIFIED BOW =  Is used generally on Mid-size to Large Hull = 90' to 200' lengths in "Line & Long Haul" class vessel designs.    Note its" Hard Chine" = Slanted Hull Sides, which pass more water under the slanted hull-sides, to the stern for better Thrust & Steering..   This style of bow, or overall hull is a standard design used by Jeff boat, "The Worlds Largest Inland River Shipbuilder", located on the Ohio River!    They prefer to build this hull design, but also build anything else buyer's wants, but they highly recommend their own style as any shipyard does.

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    THE SPOONBILL BOW = Is found more commonly on older vessels, usually built prior to the 1960's on larger hulls = Trip Boats / Line & Long Haul - towboats.   But has been used on smaller boats too, and gives the hull a somewhat rounded shape at its corners.    And avoids the problem of the hull - easily being rolled over, if it goes aground, since only the hulls sides are rounded at their edges - Bow & Mid Ship points.    

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    THE SCOW BOW = Is used on all types of towboats - Small & Large.    Class or size of the boat, makes little difference to this design, being the simplest to build.    Note the Scow Bow - simple shapes, which are formed into rounded edges at its lower - hull sides.    The only problem with this design, deals with keeping its bilges - dry, to the hulls - flat bottom shape, making it difficult to keep dry, unlike a vessel with a slightly rounded hull bottom.    With the bilges - dry, its stable = as a Rock, however if a few inches of water are allowed to accumulate in the bilge, it becomes a unstable and easily tips-over and sinks.    Probably the most often used design, for smaller vessels as well as barges, its faults are small,  compared to its success.    Dravo Shipyard of Neville Island PA. ( now out of business ), used this style of hull,  on their large boats.    And their smaller partner company - Steel Ship, also built such hulls, and was once located at Pine Bluff Ark and built many smaller Tenders & Trip boats, before it closed.

    FINAL COMMENTS ....... As I said, there are many ways to marry a Bow, to the rest of a hull, regardless of its shape.    And some very unique shipyard styles have appeared, like during the early 40's to 60's when towboats were commonly given  what was called a "Sway-Back" style of hull, typical of their ole steamboat days in overall hull shapes.    This just means the builder gave the hull a slight amount of curve to its main deck, and amidships section was lower to the waterlines, then the Bow or Stern sections were. .... Sorta low in the middle and High on both ends!    And a "Swayback Hull, if it took on water in the bilge, continued to stay stable because the water always went to the hulls - lowest points.    And there - it could easily be pumped off, without causing the boat to become - unstable.     However, on flat bottom hulls, you must keep a watch on the bilge's, to always keep them pumped - dry.     Because of the flat hull design, water spreads throughout the hull and can, if the boat is turned hard, cause the water to rush to the lower side and cause it to take on more water.   And you can imagine what happens - NEXT, when that Happens!

Typical - Stern Designs

Ramped, Step-Up, Sloped & Flat- Deck

    The Stern Section - can be built with or without - Tunnels, which provide deeper areas under the stern, for the steering and propulsion systems.  A tunnel hull allows enlarged props or wheels to be installed, which naturally increases thrust & power..   The basic's of how shipyards use certain styles or characteristics in hulls, sometimes can be confusing.    And some hull traits are common to only one shipyard and easily recognized, by the trained eye.    While other designs may not easily show exactly whom built them, as far as basic characteristic's - are concerned.    Here, sometimes you have to look at the vessels history, in order to see what was changed or has been modified by past ownership, because these towboats - Never Stay The Same!    Damaged, or in need of rebuilding, often whole sections of the vessel may have been changed or altered, which removes original characteristics, and here - the Vessels Records, which can be located in books like the "IRR" = Inland River Record Book, report on the Vessels past.    So you can determine what has been changed, improved or removed, if you know where to look!

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       Types of - Stern Sections  ( Top to Bottom ) NOTE .... The Three Top Drawings ... show stern sections = equipped with Tunnels ... Which allow the use of larger Props = Wheels, to increase horsepower and thrust.   Especially done with towboats equipped with "Kort Nozzles", which are embedded up into the Tunnel - stern, to protect them further ....   BOTTOM DRAWING = shows a stern that "Is Not Equipped" with a Tunnel, forcing the use of smaller - Props = Wheels.    Stern Hull sections = like this, are built typically in smaller Utility & Tender class boats, that aren't usually over 50' length and is the most basic style used today.

    The Mid-section of the hull, is the deepest part, where most of the inner systems that run the vessel, are located.    From the Main Engines, Fuel Tanks, Water Tanks, Sewage Systems, Used Oil and Bilge holding tanks.    Its usually all fitted into the overall hull, but most of it is located in the deepest part of this sections designs.    The Fuel Tanks, take up most of the space, with the main engines the second largest items.    And this section of the hull, may be designed differently at either end, depending upon the style of the Bow or Stern Sections, that are married to It.    

Hulls, Rudders, Kort's & Keel Coolers

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    The Stern - Section of a Line Hauler    As its built and laid - Upside Down!    Note the "Tunnel Hull" design that includes the "Kort Nozzles", installed into the hulls configuration on this boat.    This is an older "Dravo Ship" design, of about 5,000 horsepower, judging by the hull diameters and the size of the kort's.   The size of the Kort's, indicate the Wheels = a term for Props, from steamboat days.    Will have about a 10' diameter, once they installed under this 12' overall drafted hull.   ( Photo by Joe E. Brown )

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     The Business End     Showing a closer view of the Kort Nozzle and Flanking & Stern Rudder steering..   Note the "Brace Ribs" along the sides of the rudders!    These rudders were designed so that their - lower sections, can break off, if they are struck by an object.  This way - the boat may lose only a portion of a rudder and steering ability, yet still able to continue until later repairs can be made later.  Note also - Water around this area of the stern, is only inches from the surface along the Hull Sides.   The notice how the Wheel and Kort, is actually embedded up into the tunnel hull, allowing an increase sized system, for better thrust, without lowering the props to dangerous points.  This further protects the steering systems from damage, which the hull takes the worst of any abused punishment, usually, as a rule.    ( Photo by Joe E. Brown )     Remember - The theory of towboat designs, are unlike any other.     These boats can't take anything for granted, like having plenty of "Deep Water" under their Hull, unlike others that work in deep water!

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    Hull Coolers   - also called "Skin or Keel Coolers", which are "Radiators" of the boats main engines and/or its Auxiliary Engines.    Mounted along the hull- sides or along the bottom of the hull, where they can cool the engines with water that passes through them.    Note in this photo, how they run the entire length of the hulls - deeper mid section, about 2 1/2 feet from the top of the main deck, or so-called "Boiler Deck"    They will be - just under the surface, or waterline of the hull, once its afloat.    And Both Sides = Port & Starboard have "Coolers", including smaller systems for the Auxiliary Engines  .... ( Photo by Joe E. Brown )

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Last Updated On 01/31/08 . With Fueled By

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