US2448075A - Retractable sponson - Google Patents

Description

I- 1948- I w. A. BORTNER 2,

RETRACTABLE SPONSON Filed Sept. 14, 1945 2 Sheets-Sheet l WILLIAM A. BORTNER 31, 1948- w. A. BORTNER RETRACTABLE SPONSON 2 Sheets-Sheet 2 Filed Sept. 14. 1945 5.. w; w u V8 :U/ilwwfilrlwww1ylwww|bwvwi E s ,2 j -M, 1 $0 1/) n1}. 8 2 7 M. v z a m 4 I 7\ I F 2 gwum WILLIAM A BORTNER Patented Aug. 31, 1948 j sT-ATEs PATENT OFFlCEp RETRACTABLE SPONSON I William A. Bortner, Baltimore, Md., assignor to -The Glenn L. Martin Company, Middle River,

Md.,.a corporation of Maryland 14, 1945, Serial No. 616,255

4 Claims. (01. 244-102) Application September This invention relates to spray control onflying boats and moreparticularly to retractable spray control strips'mounted along'the chine of. the. --hull.' I I when a flying'boat takes off from the water, it is -moved forwardly through the water by the power of the engines and propellers until suflicient speed is obtained'so that the hull is raised from its normal waterline floating position until it planes onthe contoured botto'm of the hull. Asmore speed is attained, the flyingboat is supported partially by planing on the hull bottom and partially by the aerodynamic lift of the airfoils." When thehull bottoms are formed to a contour that give a good planing surface they are very apt to cause aheavy spray tube-thrown off, upwardly and outwardly'from the chine of the hull. As the hull moves forwardly thisheavy spray can :cause serious interference with the tail surfaces: of the'airplane' and therefore with some hull designs, it is necessary to locate these stall surfaces'high off the water line. In some instances thespray will'interfere with the engine and propellers.

The present inventionhas-for its object retractable spray "strips extending along the chine in the side'of the hull-of a seaplane. These spray strips extend from a position forwardly of the leading'edge of the wing to a point under the wing along the-chine; The spray strips so arrangedare retractable into recesses in the sides of the hull and their'outward surfaces present a smooth continuous hull surface so that a minium of drag is offered by this structure when the seaplane is in flight. In the extended position these spray strips extend'laterally oi the chine to direct spray from the planting portions of the hull outwardly and downwardly, thus affording additional plane area and directional control for the spray from the hull.

A further object of this invention is the provision for a built-in hydraulically actuated mechanism for retracting the spray strips after take-off; 1

A further object of this invention is the pro visionofameans to control the spray from the chines of the hull to direct the spray so that it will not interfere with the functioning of the engine and propellers and control surfaces on the empennage. i V

Further and other objects will become apparent from the description of the accompanying drawings which form a part of this disclosure and in which like numerals refer to like parts.

In the drawings:

Figure 1 shows a fragmentary-perspective viewv ofv a flying boat embodying the invention.

1 Figure 2 is a side sectional view through-the hull showing thespray strip in the extended and retracted positions.

Figure 3 is a plan sectional view through the side of the hull of the flying'boat.

Figure 4 is a perspective view showing the retracting mechanism for the spray strips.

The spray strips shown in Figure 1 comprise sections I to 4 hinged along the chine attached to each side of the seaplane hull. In Figure 1,

the spray strip sections are shown in the open.

cr'operative position. For purposes of illustratingthe application of the invention, the-spray,

strips are shown under the wing and extending forward of the leading edge of the wing,- but it should be understood that these strips can-be located wherever objectionable spray may be encountered. The spray from the chine of -a seaplanehull has always been a problem and in some cases seriouslyinterferes with good design of the airplane or the take-off characteristics of the plane. In some seaplane designs, a gull wing is employed to liftthe engines and propellers .up away from the'surface of the water-and out of the spray. But as seaplane sizes increase and greater spray isencountered from larger hulls,

the gull wing construction presents a serious fabrication problem so that it is desirable to use, a straight high wing extending from the top :ofv

the-hull on which the-engines and propellers are supported. The hull can be designed to minimize the spray but it can further be controlled through the use of the spray strips of this invention.

Due to the long sweeping curvature of the hull along the chine, it is necessary that the spray strip be fabricated in sections. These sections may be extended into their operative position simultaneously'or as many sectionsmay be extended as observation of the spray condition indicates. are:

necessary.

Figures 2 and 3 show the relationship of the spray strips to the'hull in closed position. The

spray'strips shown in Figures 2 to 4 for purposes of more clearly showingthe invention 'are views through section 4 of the spray strip'shown in Figure l. The spray strip sections each comprise two-portions, section 4 shown in Figures 2 to4 comprise members 6 and l hinged by a piano hinge at 8. These members are reinforced on the inside but offer a plane, smooth surface on the outside so that in the retracted position they maintain smooth and continuous the side of the hull. Reinforcing structures 24 and 25 are secured to the surface sheets to render members and 1 suiilciently rigid to withstand the stresses involved when in the operative position. The

lower end of section 6 is hinged at 9 to the chine of the seaplane hull. The members forming sponson 4 are shown in the operative position in phantom as portion 6' and 1. The sections are capable of being moved into a flush position shown at 6 and 1 in the side of the seaplane hull. Cavities In, II, I! and I3 formed in the side of the hull above the chine accommodate the structure of the spray strip sections I to 4.

The movement of the members forming the spray strips is accomplished by a hydraulic cylinder I 4 having fluid connections l5 and Hi to the hydraulic system. The thrust member I! of the hydraulic cylinder carries a fitting on its outer end l8 to which is attached a bracket l9 to support rollers 20. These rollers are guided by roller channels 2! secured in the cavities in the side of the hull. hinged at 22 to a bracket 23, also secured to fitting Hi. It will be noted in Figure 1 that the adjacent ends of the spray strips or sponsons such as the ends of sponsons 3 and 4 can be connected to a single fitting I8 so that one power unit may operate the adjacent ends of the sponson sections. sponson construction is located as shown in Figure 1 along the chine so that spray from that portion of the hull extending forward ofthe first step will be deflected outwardly and downwardly;

Priorto take-ofi the hull is afloat and depending upon the water line some portion of the spray strip or some sections "may be under water. As the hull moves forwardly, it rises out of the water and begins to plane on the bottom surface of the hall. the seaplane gathers speed the hull rides on the forward step and from this time until take off it is most important to control or direct the spray from the hull away from the critical operating parts of the-airplane mentioned above. when it is observed that the spray is objectionable any or all of the spray strips may be extended to the operative position shown in Figure 2 Portion 6 shown in the extended position 6 terms a smooth continuous extension of the hull bottom which directs the spray outwardly and downwardly that would normally move upwardly around the chine and interfere with the control orop-era'tion of the seaplane. As soon as the airplane leaves the surface of the water the spray strips may be moved to the retracted position and thereafter maintained in a closed position in the cavities to ofier little or no drag to the flight of the "airplane.

For the purposes of illustration, the sections of the spray strips in the drawings are shown with a space between the adjacent edges but depending upon the clearances and tolerances re quired, the adjacent sections of the spray strip can be as closely spaced as is practical.

It is to be understood that certain changes, alterations, modifications and substitutions can be made without departing from the spirit and scope of the appended claims.

I claim as my invention:

l. A seaplane hull having a recess extending along the chine iorward and aft of the leading edge. of the wing, apa'nel pivoted along the chine The upper ends of member I areadapted to move to a position extending laterally of said hull so that the outer surface of said panel forms a continuation of the bottom thereof, a second panel pivoted to the outer end of said first panel, a bracket secured to the upper end of said second panel, track means in said. recess and guide means [on said bracket moving in said track means, hydraulic means secured to said bracket to retract said hinged panels into said cavity and to extend said first mentioned panel into its operative position forming an extension of the hull bottom.

2. In combination in a seaplane hull having a recess extending along the chine forward and aft of the leadin edge of the wing, a panel pivoted along the chine adapted to move to a position extending laterally of the seaplane hull forming a continuation of the bottom thereof, a second panel pivoted to the outer end of said first panel, a bracket secured to the upper end of said second panel, track means in said recess and rollers on said bracket moving in said track means, a hydraulic cylinder secured to said bracket to retract said hinged panels into said cavity and to extend said first mentioned panel into its operative position to form an extension of the hull bottom.

3. A seaplane hull having asha'll'ow recess formed in the side thereof, above the chine for ward and aft of the leading edge of the wing, a sectional spray strip including pairs of panels placed one above the other mounted in said re cess, having the outer surface. flush with the surface of the seaplane hull, the lower edge. of the lower panel being hinged along the chine, the upper edge of the lower panel being hinged to the lower edge of the upper panel, the top edge of. the upper panel being secured to a mechanismmounted within said recess to lower each pair of.

panels so that the lower panel is moved to a position extending laterally from said so that. the outer surface of said panel forms a continua.- tion of the bottom thereof, along the chine.

4. A seaplane hull having a sectional spray strip comprising panels hingedly secured along the chine adapt-ed to be moved. to a position ex tending lateral-1y therefrom, the outer surface thereof forming a continuation. of the bottom of said seaplane hull, other panels. each having one edge secured to each of said first mentioned panels at the outer edge thereof, bracket members secured to the upper edge of said second panel, a mechanism secured to said brackets to move the upper edge of said second panel toward said chine so that said first mentioned panel is moved to said laterally extending position.

. WILLIAM A. BORTNER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number I Name Date 21,158,266 Minsha'll et al. Apr. 4, 1939 2,320,574 Dornier- June 1, 1M3- FOREIGN PATENTS Number Country Date 842,986 France Mar. 13, 1939

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