US2371478A

US2371478A - Boat hull

Info

Publication number: US2371478A
Application number: US481819A
Authority: US
Inventors: Archie A Steele
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-04-05
Filing date: 1943-04-05
Publication date: 1945-03-13
Anticipated expiration: 1962-03-13

Description

' March 13, 1945.

A. A. STEELE BOAT um.

Filed April 5, 1945 2 Sheets-Sheet l Snventor lll I! March 13, 1945. STEELE I 2,371,478"

BOAT HULL Filed April 5, 1943 ZSheets-Sheet 22 35 I 3nventor: ARCH/E ,4. STEELE.

Patented Mar. 13, 1945 UNITED STATES PATENT OFFICE r 2,371,478 J W pon'r HULL I Archie A. Steele, Los dngeleacalif. Application April 5, 1943, Serial No. 4813319 7 Claims. (01. iii-'62)" My invention relates to boats, and relates in" particular to a combinedsail and motor driven vessel having relatively high speed under either sail or motor power, and for this reason beingespecially adapted for use as a sub-chaser or coast patrol vessel.

The usefulness and advantages of a boat of'this character may be readily perceived from a consideration of a proposed 96-foot ship having comfortable accommodations for eighteen men. -A vessel as above indicated, rn'ade in accordance with my invention and equipped with submarine and atmosphericflistening devices, 40 mm. guns,

and depth bombs, is capable of patrolling an area at a considerable distance froma base. nary patrol service would be accomplished under sail power at a speed which would have a maximum of about 13 nautical miles per hour in a would have an approximate speed of 25 knots, so-

as to be fast enough to catch or escape from a submarine", as the case required. Cruising under sail would ordinarily require no use of fuel. In view of this, the vessel would have a wide range of operation. Also, the form embodied in the hu1 of the vessel makes it possible to locate fuel tanks, water tanks, andmotors below the water level.

It is an object of my invention to provide a vessel suitable for operation in all kinds of weather, either under sail or motor power, at

speeds such as indicated in the foregoing, this.

vessel having a, hull of novel form, making it suitable for use either as a sail boat or power boat. It is an object of the invention to provide in a' vessel of the class described a hull having [a displacement keel merging through curved surfaces with concave bottom portions leading to chines which are of a characteristic form and contribute to the accomplishment of the results forming part of the objectives of the present invention,

A further object of the invention is to provide a hull capable of greater speed through the water than ordinarydisplacement type of hulls of equivalent size, wherein the lines from bow to stem are relatively straight and the hollow; body sections between the keeland the chinesflareso formed;

Its ordi that they will carrytrapped airunder the vessel fora distance more than 50% of the water length thereof. 7

It is an object of the invention .to provide ahull of the type described which,.'as the result of a combination of curves and nearly straight buttook lines, is considerably faster than one and one half times the square root of the water line length,"whichiisithe accepted maximum speed in nautical miles per hour for adisplacement type hull;

A further object of the invention is to provide a hull, the speed. of which under sail isenhanced by the boat riding on her own bow wave when heeled over under sail, thereby decreasing the "wetted surface by entrapping air in the space supplemented also. if desired by running the exespecially provided between the chines and the underpower operation a wetted surface decreased I by the entrapment of air from the bow wave,

haustfrom the 'motors, aide'dby blowers, so that they will pass into the concaveareas under water, which concave areas will retain the .air until it reaches the after part of the hull where it will help nullify suction and stem quarter wave for-- mation."

A further object of the invention is to provide a hull which,.due to the slight curvature of selected buttocklineswill not squat when propelled forwardly.

Further objects tion will be-brought out in the following part of the specification. I

Referring to the drawings which are for illustrative purposes only;

Fig. 1 is an elevational view of a vessel having a hull embodying my invention.

Fig. 2-is a schematic plan view showing the body outline of the hull disclosed in Fig. 1'.

Fig. 3 is a-sectional view taken as indicated by the .line 3--3 of Fig.1.

Fig. 4 is a sectional view on the-plane indicated by the. line 4-4 of Fig. 1.

by the. line '5--5 of Fig. 1. t

Fig. 6, is a sectional view taken as indicated by the line 6--6 of Fig. -1.

Fig. '7 is a sectional view, to reduced scale, taken on a vertical .plane represented by the line 5' of Fig. 2. F

The boat shown in Fig. l comprisesa hull Ill and'a superstruetureshown as rigging ll includmg a mast l2 and sails l3. In Fig.1 a keel His showm .Inflthis description the .l eel' M will. be

and advantages of the inven- Fig. 5 is a sectional view taken as indicated I regarded as a part of the hull l0, and in keeping therewith, the upper portion of 'the hull 10, from which the keel I4 downwardly projects, will be referred to as the body portion l5 of the hull In.

The body portion i5 of the hull l0 comprises side walls l6 which meet at the prow I! above the water line of the vessel, diverge rearwardly to a maximum width at substantially the midsection of the body l5, and then converge toward the stem. The side walls It each have a lower edge I8. These lower edges I8 have their front ends l9 starting above the Water line and sloping downward so as to pass below the water line amidships of the vessel, as shown in Fig. 1. I have referred to the keel M as a flotation keel for the reason that it is characterized by its capacity to float the entire weight of the vessel so that the body portion [5 of the hull I0 is substantially entirely above the water line 20. keeping therewith, I have made the keel M of such volume that its displacement is substantially equal to the displacement of the entire vessel equipped and carrying its normal crew. The prow end 2| of the keel I4 is relatively sharp, as shown in Fig. 6, so that it will have acceptable water cleavage, but, as shown in- Figs. 5 and 4, the width of the keel I4 is broadened or widened as its upward extension is completed. Then, as the keel progresses rearward through'the vertical plane indicated by the line 33, it is tapered ofi, as shown in Fig. 3, so that when the edge 22, Fig. 1, is reached, the keel will have a width considerably less than the diameter of the propeller which operates in a recess 23 forming' an opening between the edge 22 and therudder 24 which is hinged thereto. v

Amidships of the hull In the keel is of such width that a chamber 25 is provided, the upper portion of this chamber 25 being of ample size to receive the combustion engin 26 which drives the propeller 21'. As shown in Fig. 4, the keel M has side Walls 21, the lower portions 28 of which are distinctly upright in position, or, in other Words, are vertically disposed. By this descriptive wording we mean that the lower portions 28 of the side walls 21 are near vertical as distinguished from the upper portions 29 of the side walls which are near horizontal so as to form bottom or bilge walls below the body portion [5 of the hull 10. The lateral edge portions 30 of the keel side walls 21 are bent downwardly slightly from a horizontal plane so as to meet the lower edges of the body side walls [6 in a manner to form chines 3|, the bow portions of which lie above the water line, and the amidships portions of which project below the water line when the hull is riding level as shown in Fig. 1. The stem portions of the chines 3| -lie substan: tially at the water line, or drop below whenthe vessel is propelled forward at reasonable speed under motor power. In the preferred form of construction, the chines begin near the stem and extend to or near thetransom, the length of the chines being such that concavities or inverted channels 33 are formed lengthwise of the vessel and inwardly of the chines 3|, of such length that the concavities will receive air at the front ends thereof during forward-motion of the vessel under load, and relatively carry this air under the side portions of the hull body IE to the stern and discharge the air at the after part of the hull so that it will break or partially break the ordinarily encountered stern suction and diminish stern quarter wave formation. Although the 'keel l4 has the displacement characteristics hereinabove described, its slenderness is such that the buttock lines of the keel portion of the hull have small curvature,'and as the result of the combination of transverse curves and nearly straightbuttock lines, the ship is not only fast under sail power, but also exceptionally fast when under mechanical propulsion.

In Figs. 2 and 4 the line 5''5' indicates a vertical plane parallel to the vertical median plane a-a of the hull. The plane 5' 5 is positioned a distance x from the median plane aa,' which is substantially one-half the greatest distance 1/ from the median plane a-ct to the chine. This distance a: is substantially one-fourth of the V greatest width of the underwater portion of the hull. In keeping with the relation of this dimension at to the width of the wetted or underwater portion-of the hull, I have referred to the area q of the hull between the plane 5-5' and the portion c of the chine lying distally as the outer quarter of the hull. This outer quarter q is duplicated on the left side ofthe hull as indicated at q in Fig. 4.

Between the plane 5'-.-5' of Fig. 2 and the most distal part of the chine portion 0, I have shown buttock lines 6, "l, 8, and 9. 'As viewed from above, these buttock lines appear straight. An important feature of the invention is that these buttock lines when viewed from the side have a curvature ofless than one inch in ten feet from substantially the middle section of the hull to the after ends of the individual buttock lines. The forward portions of the buttock lines may be of slightly greater curvature than this. In Fig. 7, the lower line 5 of the section on line 55 comprises the buttock line at the medial limit of the outer quarter q and has the greatest curvature of any of the buttock lines of the outer quarter section. It will be noted that the after portion 5a thereof is nearly straight, having a curvature of not greater than one inch in ten feet; whereas, the forward portion 5b has slightly greater curvature.

This desired effect is enhanced by the boat riding on her own bow wave when she is heeled over under sail, at which time the wetted surface is decreased by the trapping of air between the depressed chine and the keel. Th spacing and depth of the chines 3| make possible decreasin of the external metal ballasts, 35 to a minimum.

As indicated in Fig. 1, fuel tanks 31 may be disposed in the lower part of the chamber 25 of the keel portion l4, and as indicated at 38, a water tank may be located in th forward portion of the chamber 25, below the water line.

I claim as my invention:

water line; and a flotation keel having a displacement substantially equal to the weight of the vessel disposed centrally below said body, said keel having a vertical depth at least as great as the depth of said body, and having side walls, the

lower central portions of which are substantially vertically disposed and the upper portions of which curve outwardly to meet the lower edges of said body side walls in, a manner to form chines,

the front ends of which are disposed above they water line of the vessel and the intermediate". portions of which chines lie -closeto the water where they meet said body-sidewalls so that inverted longitudinal channels are thereby formed under saidbody to trap-air during forward motion of the vessel andguide the air'toward the stern. of the vessel, said keel side walls being so spaced that the intermediate portions thereof will define a chamber of a size to receive a motor to power the vessel.

2. In a hull for a sail and power vessel of the character described, the combination of: a body having side walls extending from the bow portion to the stern portion thereof, the bow ends of the lower edges of said side walls starting at a point above the water line of the vessel and sloping downward and rearward so as to pass below said waterline; and a flotation keel having a displacement substantially equal to the weight of the vessel disposed centrally below said body, said keel having a vertical depth at least as great as the depth of said body, and having side walls, lower portions of which are substantially vertically disposed and the upper portions of which curve outwardly to meet the lower edges of said body side walls in a manner to form chines, the front ends of which are disposed above the water line of the vessel and the intermediate portions of which chines lie close to the water line, the lateral extremities of the central portions of said keel side walls being bent downward where they meet said body side walls so that inverted longi tudinal channels are thereby formed under said line, the lateral extremities ofthe middle portions of said keel side .walls being bent downward body to trap air during forward motion of the vessel and guide the air toward the stern of the vessel and the forward ends of the side portions of said keel side walls rising above the water line of the vessel and meeting the bow portions of said body side walls.

3. In a hull for a sail and power Vessel of the character described, the combination of: a body having side walls extending from the bow portion to the stern portion thereof, the bow ends of the lower edges of said side walls starting at apoint above the water line of the vessel and sloping downward and rearward so as to pass below said water line; and a flotation keel having a displacement substantially equal to the weight of the vessel disposed centrally below said body, said keel having side walls, lower portions of which are substantially vertically disposed and the upper portions of which curve outwardly to meet the lower edges of said body sidekwalls'in a manner to form chines, the front ends of which are disposed above the water line of the vessel and the intermediate portions of which chines lie close to the water line, lateral extremities of said keel side walls being bent downward where they meet said body side walls so that inverted longitudinal channels are thereby formed under said body to trap air during forward motion of the vessel and guide the air toward the stern of the vessel, said keel side walls being so spaced that the intermediate portions thereof will define a chamber of a size to receive a motor to power the vessel.

4. In a hull for a sail and power vessel of the character described, the combination of: a body having side walls extending from the bow portion to the stern portion thereof, the bow ends of the lower edges of said side walls starting at a point above the water line-of the vessel and sloping downward and rearward so asto pass below said water line; and a flotation keel having a displacement substantially equal to the weight of the vessel disposed centrally below-said body, said keel having sidewalls, the lower centralportlons;

of which'a're substantially vertically disposed and the-upper portions of which curve outwardly to, meet the lower edges of said body side wallsain a manner to form chines, the-front ends: of which are disposed above the water line of the vessel and the intermediate portions of which chines lie close to the water line, lateral extremities of said keel side walls being bent downward where they meet said body sidewalls so that inverted longitudinal channels are thereby formed under said body to trap air during forward motion of, the vessel and guide the air toward the stern of the vessel and the forward ends of the side portions of said keel side walls rising above the water line of the vessel and meeting the bow portions of said body side walls.

5. In a hull for a sail and power vessel of the character described, the combination of z a body having side walls extending from the bow'portion to the stern portion thereof and a flotation keel having atdisplacement substantially equal to the weight of the vessel disposed centrally'belowsaid body, said keel having a vertical depth at least as great as the depth of said body, and having side walls, the lower central portions of which are substantially vertically disposed and the upper portions of which curve outwardly to meet the lower edges of said body side walls in a manner to form chines, the front ends of which are disposed above the water line of the vessel and the intermediate portions of which chines lie close to the water line, the lateral extremities of the central portions of said keel side walls'being bent downward where they meet said body side walls so that inverted longitudinal channels are thereby formed under said body to trap air during forward motion of the vessel and guide the air toward the stern of the vessel.

6. In a hull for a sail and power vessel of the character described, the combination of: a body having side walls extending from the bow portion to the stern portion thereof; and a flotation ,keel having a displacement substantially equal to the weight of the vessel disposed centrally below said body, said keel having side walls, the lower central portions of which are substantially vertically disposed and the upper portions of which curve outwardly to meet thelower edges of said body side walls in a manner to form chines, the front ends of which chines are'disposed above the water line of the vessel, and the intermediate portions of which chines lie close to the water line, the upper portions of said keel side walls projecting downwardly along the line of meeting of said body side walls and said keel side walls so that inverted longitudinal channels are thereby formed under the central portion of said body to trap air during forward motion of the vessel and guide the air toward the stern of the vessel. 7

7; In a hull for a sail and power vessel of the character described, the combination of a body having side walls extending from the bow portion.

to the stern portion thereof; and a flotation keel having a displacement substantially equal to the weight of the vessel disposed centrally below said body, said keel having a vertical depth at least as great as the depth of said body, and having side walls, the lower central portions of which are substantially vertically disposed and the upper portions of which curve outwardly to form outer quarters, the buttock lines of which have an average curve of not greater than about one inch in ten feet, the lateral extremes of said upper portions meeting the lower edges 01' said body side walls in'a manner to form chines, the front ends of which chines are disposed above the water line of the vessel and the intermediate portions of which chines lie close to the water line and project downwardly along the line of meeting of the intermediate portions of said body side walls and the intermediate portions of said keel side walls so that inverted longitudinal channels are thereby formed under said body to trap air during forward 'motion of the vessel and guide the air toward the stern of the vessel.

ARCHIE A. STEELE.