Patent Publication Number: US-6702630-B2

Title: Auxiliary keel system for marine crafts powered by jet propulsion systems

Description:
RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 10/100,330 filed Mar. 18, 2002, now U.S. Pat. No. 6,561,858 issued May 13, 2003. 
    
    
     The invention relates to an auxiliary system for providing positive steering to marine crafts using jet propulsion systems, typically personal jet driven watercrafts such as jet boats and jet skis. 
     By way of background, there are two types of jet propulsion systems currently in use. The first type most commonly used is found on personal watercrafts usually referred to as Jet Skis. This type uses a directional nozzle. The nozzle turns from side to side directing water from the jet to change the direction of the watercraft. 
     The second type is commonly used on Jet Boats. This type of system incorporates a movable hood or cover over the directional nozzle to force the water from the jet below the boat to add reverse thrust and allows the boat to back up. For forward thrust, it is pulled up above the jet nozzle. 
     In both types, the steering of the watercraft relies completely on the direction and force of the water being expelled from the directional nozzle. This steering method is extremely unreliable as it responds slowly and fails totally if power is reduced or turned off. As a result, there have been many deadly accidents as a result of such watercraft not being able to quickly and positively respond to a need for directional change at any speed, even if engine power is cut off. 
     The present invention addresses this steering deficiency currently found in existing watercrafts powered by jet propulsion systems by incorporating an auxiliary keel system to dramatically enhance the steering performance of such watercrafts. In normal operation, the keel steering enhances the watercraft&#39;s maneuverability with immediate and controlled response. 
     In operating conditions where the operator reduces the jet power or stalls the engine, the keel steering takes over and the watercraft will steer accurately. Consequently, the present invention makes the operation of jet propelled watercrafts more enjoyable and, more importantly, much safer. 
     Although the present invention is more fully described hereinafter, in general, the present invention includes, among other features, a combination of keel members attached to a stern section of a hull. The keels are interconnected using tie rods to the directional steering drive assembly. In other embodiments, the keels are instead attached directly to the directional nozzle or incorporated into the manufacture of the directional nozzle as one piece, and where a hood is included in the directional nozzle assembly, notches are included in the keels to allow for full operation of the hood into its lowest position. For the latter embodiments, although one center keel will work, a divergently depending two keel system or a two keel system together with a center keel further enhance the watercraft steering performance. 
     For safety purposes, the bottom edges of the keels are preferably rounded off with a radius of at least {fraction (3/16)} inch. This feature can also be included by gradually tapering the keels to widen at the bottom edges to accommodate the rounded bottoms. 
     In addition, in circumstances where the keel member are designed to be part of the directional nozzle, then the tapered keel may be hollow such that a portion of the outlet flow of water can also be directed through the hollow portion of the keel members and exit the back edge of the keel members in a substantially parallel direction to the general flow of the water out the directional nozzle. 
     If more positive reaction to steering is desired or even less positive reaction to steering is desired, than the contemplated 1:1 response in the embodiment using tie rods described below, an odd number of apertures, linearly arranged where the tie rod ends are connected together could be provided so that an owner can adjust the sensitivity of the steering response by connecting the tie rod ends to the central aperture for 1:1 response, to an aperture closer to the stern for a little less rapid and lesser response (less than 1:1) and to an aperture further away for a more rapid and greater response (greater than 1:1). 
     In still another embodiment of the invention, two more keel members can be incorporated into a directional nozzle with a ridge being formed along either side of the directional nozzle so as to form cupped sides between each outside keel member and the ridges. It is also preferred, but not necessary, that a cup be formed on the directional nozzle between the keel members as well. Where the outside keel members depend relatively straight down from the directional nozzle, it is recommended that the most bottom ends of each outside keel member (when two or three keel members are included) be formed to bow or slightly bend outwardly. 
    
    
     In the accompanying drawings: 
     FIG. 1 a  is a depiction of the present invention attached to a jet boat with the hood in the “UP” position for forward motion; 
     FIG. 1 b  is a depiction of the embodiment of FIG. 1 a  with the directional nozzle and the keels of the present invention turned to make a right turn with the jet boat; 
     FIG. 1 c  is a depiction of the embodiment of FIG. 1 a  with the hood in the “DOWN” position for creating a reverse thrust in the jet boat; 
     FIG. 1 d  is a depiction of one application of the present invention used in FIGS. 1 a - 1   c;    
     FIG. 1 e  is a depiction of a practical application of an alternative attachment bracket to interconnect the tie rods from the directional nozzle drive assembly; 
     FIG. 1 f  is a depiction of one example for providing angular adjustment means to accommodate the angle of the stern; 
     FIG. 2 a  is a depiction of another embodiment of the present invention that provides for the installation of a keel system directly to the directional nozzle outlet; 
     FIG. 2 b  is a depiction of another embodiment of the invention depicted in FIG. 2 a , except that the keels members are detachable from the C-shaped portion that is mounted over the directional nozzle; 
     FIG. 3 a  is a depiction of another embodiment of the present invention for use on personal watercrafts such as jet skis; 
     FIG. 3 b  is a depiction of another embodiment of the invention of FIG. 3 a , except that the generally C-shaped portion is formed by the assembly of parts that allows for the keel members to be replaced without having to replace the portion that attaches to the directional nozzle; 
     FIG. 3 c  is a depiction of the invention of either FIG. 3 a  or FIG. 3 b  attached to the directional nozzle of a jet ski; 
     FIG. 3 d  is a representation of the invention of FIGS. 3 a  or  3   b  attached to a jet ski with the normal forward movement water line and the keel members submerged below the water line; 
     FIG. 3 e  is a further representation as in FIG. 3 d  except that the jet ski is leaning to the starboard to initiate a right turn and the lowered right side keel member provides control assistance to the operator; 
     FIG. 3 f  is also a further representation as in FIG. 3 d  except that when the personal watercraft proceeds at high speeds, the keel members remain relatively below the water line for maintaining turn control at high speeds; 
     FIG. 4 depicts another embodiment where the keel members are part of the directional nozzle; 
     FIG. 5 a  is a conceptual depiction of a directional nozzle with a single center keel depending therefrom; 
     FIG. 5 b  is a conceptual depiction of a directional nozzle with two spaced-apart and divergently depending keel members depending from the nozzle; 
     FIG. 5 c  is a conceptual depiction of a directional nozzle with three keel members; 
     FIG. 6 a  is a conceptual depiction of a directional nozzle with a detachable single center keel depending therefrom; 
     FIG. 6 b  is a conceptual depiction of a directional nozzle with two detachable spaced-apart and divergently depending keel members depending from the nozzle; 
     FIG. 6 c  is a conceptual depiction of a directional nozzle with three detachable keel members depending from the nozzle; 
     FIG. 7 a  is a depiction of another embodiment of the keel with a rounded portion on its bottom edge; 
     FIG. 7 b  is a cross-sectional view taken from FIG. 7 a;    
     FIG. 8 a  is a depiction of another embodiment of the keel similar to that of FIG. 7 a , except that the rounded portion is formed from a gradual tapering of the keel member; 
     FIG. 8 b  is cross-sectional view taken from FIG. 8 a;    
     FIG. 9 is a depiction of a typical tie rod connector with an odd number of tie rod connector apertures for adjusting the sensitivity of the steering response; 
     FIG. 10 is a depiction of an embodiment similar to FIG. 9, except that it is incorporated into a universal mount that bolts to assorted jet nozzles and is formed to clear any reverse hoods while operates the tie rods; 
     FIGS. 11 a  and  11   b  are representative depictions of a lower cross-sectional portion of a directional nozzle end, showing an example of up to three keel members depending from the nozzle; 
     FIGS. 12 a  and  12   b  are representative depictions of a lower cross-sectional portion of a directional nozzle end, showing an example of up to three keel members depending from the nozzle, similar to that of FIGS. 11 a  and  11   b  except that the tapered keel(s) are hollow such that a portion of the outlet flow of water can also be directed through the hollow portion of the keel members and exit the back edge of the keel members; and 
     FIGS. 13 a  and  13   b  are schematic depictions of another embodiment wherein as an example, two keel members depend from the nozzle and a longitudinal ridge is formed along either side of the directional nozzle so as to form cupped sides between each keel member and the ridges, and an inverted cup-shaped is also formed on the directional nozzle between the keel members. 
    
    
     Referring now to the drawings, FIGS. 1 a - 1   e  disclose one embodiment of the present invention, which is an auxiliary keel system and is depicted generally as  10 . The present invention depicted in these Figures is an auxiliary keel system  10  for a jet propelled watercraft  12  having a directional nozzle drive assembly  14  at the stern  12   a  of the watercraft  12  and a movable hood  16  that rotates over a directional nozzle  18  to downwardly direct and force water from the directional nozzle  18  below the watercraft  12  for providing reverse thrust. 
     One embodiment of the present invention is an auxiliary keel system  10  which comprises two tie rod members  19 , each having a first end  19   a  and a second end  19   b ; and means  20  for attaching the first end  19   a  of each tie rod member  19  to an external portion  22  of the directional nozzle drive assembly  14 , wherein the means  20  for attaching the first end  19   a  of each tie rod member  19  to the external portion  22  of the directional nozzle drive assembly  14  moves in unison with the movement of the directional nozzle  18 . 
     As shown in FIG. 1 b  by the directional arrows for the keels  26  and the directional nozzle  18 , the jet boat  12  is depicted as making a right turn and the nozzle  18  and keels  26  move in unison. As the means  20  for attaching the first end  19   a  of each tie rod member  19  to the directional nozzle drive assembly  14  rotates with the movement of the drive assembly  14 , the first end  19   a  of the tie rod members  19  pivots at location  24  as shown in FIGS. 1 a - 1   e.    
     The first end  19   a  of each tie rod member  19  and the means  20  for attaching the first end  19   a  of each tie rod member  19  to the external portion  22  of the directional nozzle drive assembly  14  is engaged such that the first end  19   a  of each tie rod member  19  is allowed to pivot at location  24  with the movement of the directional nozzle  18 . 
     As shown in the drawings, the tie rod members  19  may be made from round rod and formed to accommodate the installation on the stern  12   a  and drive assembly  14 . The tie rod members  19  may be made from steel or aluminum but certainly other products in the polymer industry may be considered. Each end typically has a flat portion with an eyelet through which a pin in inserted about which the tie rod member  19  moves and rotates as the system  10  is operated. 
     FIGS. 1 a - 1   d  and  1   e  provide two examples of a typical application of making the means  20  for attaching the first end  19   a  of each tie rod member  19  to the external portion  22  of the directional nozzle drive assembly  14 . Both methods are designed to avoid interference with the operation of the hood  16 . In FIGS. 1 a - 1   d , the attachment means  20  is designed as a flanged plate for bolting to the drive assembly  14 , with an arm that rises and projected rearward away from the stern  12   a  to a fork like engagement portion through which a bolt is inserted to engage the eyelet of the tie rod members  19 . Certainly, the fork-like portion could also be wider and narrower such that two parallel pins are used to engage adjoining first ends  19   a  of the tie rod members  19 . This alternative for an attachment means  20  can be made from flat stock, round rod stock or a combination of both. 
     In FIG. 1 e , flat bar stock forming a T-shape is used whereby the transverse top of the “T” is bolted or fastened to the drive assembly  14  (se apertures for entry of fasteners into drive assembly housing) and the lower end of the leg of the “T” has the fork-like portion similar to that described above. Typically, ¼ inch thick steel or aluminum flat stock should suffice. Using this type of attachment means  20  places the attachments means  20  above the hood  16 , which avoids any interference with the hood  16 . Of course, this alternative attachment means  20  can also be made from flat stock, round rod stock or a combination of both. 
     In FIG. 1 d , it is shown from the perspective view that the apertures in attachment means  20  are recessed. This is done so that the bolt head can be recessed low enough to avoid interference with the hood  16  when it is in the “UP” position as depicted in FIG. 1 a.    
     A keel  26  is connected at each of the second end  19   b  of each tie rod member  19 . Each keel  26  has a generally planar member  28  forming the keel  26  with a generally horizontal upper edge  30 . The second end  19   b  of each tie rod member  19  is pivotally connected near a proximal end  34  of the upper edge  30 , as represented at  32 . 
     Also included is means  36  for attaching each keel  26  to the stern  12   a  of the watercraft  12 . Each means  36  for attaching the keel  26  to the stern  12   a  of the watercraft  12  further has means  38  for pivotally connecting the upper edge  30  of the keel  26  at a predetermined location between a distal end  40  of the upper edge  30  and the proximal end  34  of the upper edge  30 , preferably at an intermediate location approximately midway between the mid-point of the upper edge  30  and its distal end  40 . 
     By having the means  38  for pivotally connecting the upper edge  30  of the keel  26  at a predetermined location between a distal end  40  of the upper edge  30  and the proximal end  34  of the upper edge  30  as depicted in the drawings, hydraulic pressure from the water pressing on the front portion of the keel  26  reduces the pressure applied by the water on the rear portion of the keel  26 , which in turn reduces the stress on the steering cable and tie rod members  19 , among other components. 
     As shown in the drawings, a simple application of this pivot feature is the incorporation of a pin that vertically extends from the upper edge  30  through a shaft with provisions such as bearings which allow for lubrication of the shaft as further described below. It is even more desirable that the device be, in effect, a factory sealed greased assembly that does not require further lubrication. 
     One can surmise from the depictions that the auxiliary keel system  10  presented herein operates such that when the directional nozzle  18  moves, each keel  26  moves in unison with the directional nozzle  18  to provide enhanced steering performance. 
     The planar member  28  of each keel  26  preferably has a generally tapered arcuate-shaped leading edge  42  extending from the distal end  40  of the upper edge  30  downwardly toward a bottom edge  44  of the keel planar member  28 . 
     Each keel  26  can also be made of steel, aluminum, or durable polymers or plastic materials/composites. 
     In a preferred application, the means  38  for pivotally connecting the upper edge  30  of the keel  26  is at a predetermined angle  46  relative to the stern  12   a  of the watercraft  12  such that the upper edge  30  of the planar keel member  28  remains generally horizontal in operation and the distal end  40  of the upper edge  30  does not contact the stern  12   a  of the watercraft  12 . Preferably, means  48  for adjusting the angle  46  in relation to the stern  12   a  of the watercraft  12  for accommodating an installation such that the distal end  40  of the upper edge  30  does not contact the stern  12   a  of the watercraft  12  are included to provide more flexibility in installing the invention on existing boats  12  with different angular inclines  46  of the stern  12   a . This can be done in a number of ways known in the art, including the use of slots and multiple holes, engagement gear/teeth locking mechanisms, friction-type engagement mechanism, and similar other adjustment methods and/or combinations of those mentioned. FIG. 1 f is a conceptual example of one method where a slot with teeth-like spaced-apart protrusions are used for adjustable insertion of a pin. 
     In another embodiment, the means  36  for attaching each keel  26  to the stern  12   a  of the watercraft  12  further comprises break away means  50  for pivotally enabling the planar keel member  28  to rotate upward and away from the stern  12   a  should the planar member  28  strike an underwater object or surface thereby preventing damage to the keel  26  or to the stern  12   a  of the watercraft  12 , wherein the proximal end  34  of the upper edge  30  pivotally rotates about an axis  52  of the second end  19   b  of the tie rod member  19 . 
     In a typical application as shown in the drawings by way of example only, the break away means  50  includes a shear pin designed to shear at a predetermined impact force. The shear pin is located below a pivot pin about which the planar keel member  28  rotates away from the stern  12   a.    
     As mentioned above, although a sealed bearing or bushing containing lubrication may be used such as in a factory installation or a permanent sealing characteristic, in a preferred application, the means  38  for pivotally connecting the upper edge  30  of the keel  26  should further comprise means  58  for lubricating said means  38  for pivotally connecting the upper edge  30  of the keel  26 . As shown in the drawings, this can be done by simply adding a grease fitting where a white lithium type of grease or other marine type of grease can be periodically added. 
     Because the widths of the stern portion  12   a  of watercrafts  12  are different and some sterns  12   a  may have contours that would require someone installing the invention to adjust the length of the tie rods  19  so as to mount the keel  26  against a flat area of the stern  12   a , it is preferable that the second end  19   b  of each tie rod member  19  includes means  60  for adjusting a length of the tie rod member  19 . Although there are several ways known in the trade to provide this feature, one example as depicted in the drawings is to have the second end  19   a  be a separate piece which threads inside an axial end (see axis  52 ) of the tie rod member  19 . In this way, fine adjustments can be made by screwing the eyelet end in or out to accommodate the installation of the keel  26  to the stern  12   a.    
     Other embodiments described below were developed in anticipation that operators may want a less expensive system that provides the same benefits of the above described embodiment, that is, positive enhanced steering. 
     One such embodiment is an auxiliary keel system, depicted generally as  10   a  in FIGS. 2 a - 2   b  for a jet propelled watercraft  12 , which as above has a directional nozzle drive assembly  14  at the stern  12   a  of the watercraft  12  and a movable hood  16  as in the above described embodiment, that rotates over a directional nozzle  18  to downwardly direct and force water from the directional nozzle  18  below the watercraft  12  for providing reverse thrust, except that this auxiliary keel system  10   a  has a generally C-shaped portion  62  with means  64  for attaching the C-shaped portion  62  to an outside surface  66  of the directional nozzle  18 . The C-shaped portion  62  is adapted to extend from a first end  68  which is adapted to be located near a first side  70   a  of a notch  70  in a bottom outlet portion  70   c  of the directional nozzle  18  around a top surface  72  of the directional nozzle  18  to a second end  74  to be located near a second side  70   b  of the notch  70  in the bottom outlet portion  70   c  of the directional nozzle  18 . 
     The first and second ends  68 , 74  of the C-shaped portion  62  each have a generally planar keel member  76  angularly depending therefrom so that a distance  80  between a lower edge  82  of each planar keel member  76  is greater than another distance  80  between the first and second ends  68 , 74  of the C-shaped portion  62 . 
     As with the first described embodiment, the invention is installed such that when the directional nozzle  18  moves, the planar keel members  76  move in unison with the directional nozzle  18  to provide enhanced steering performance. 
     The means  64  for attaching the C-shaped portion  62  to the outside surface  66  of the directional nozzle  18  includes a generally U-shaped portion  84  extending from at least a portion of each of the first and second ends  68 , 74  of the C-shaped portion  62 . The U-shaped portions  84  are adapted for engaging the corresponding first and second sides  70   a , 70   b  of the notch  70  in the bottom outlet portion  70   c  of the directional nozzle  18 . 
     Typically, the means  64  for attaching the C-shaped portion to the outside surface  66  of the directional nozzle  18  further includes at least one aperture  86  in the C-shaped portion  62  for inserting means  86   a , 86   b  for fixedly engaging the C-shaped portion to the outside surface  66  of the directional nozzle  18  and for preventing the C-shaped portion  62  from sliding off the directional nozzle  18 . For the embodiment shown in either FIGS. 2 a  or  2   b , the means  86   a , 86   b  for fixedly engaging the C-shaped portion to the outside surface  66  of the directional nozzle  18  is shown as a bolt and nut. However, there are several other known types of fasteners that can be used including screws, quick release pins such as those used for vehicle hitches, etc. 
     Although a keel plate can have many leading edge designs, it is preferable that each planar keel member  76  has a generally tapered arcuate front edge  88 , that is, the edge which is nearest the stern  12   a  of the watercraft  12  when installed. 
     Because the hood  16  rotates in front of the outlet of the directional nozzle  18  when reverse thrust is needed, there is a possibility that this embodiment may prevent the hood  16  from rotating fully to its desired position. For this reason, it is preferable that each planar keel member  76  has a notched-out portion  90  near an upper back edge  82   a  of said planar keel member  76 . The notched-out portion  90 , when necessary, is sized to allow the movable hood  16  to be fully lowered to its maximum allowable position without interference from the planar keel member  76 . 
     In cases where it may be advantageous to make the keel plate member  76  from plastic or other polymeric materials so the keel plate  76  would break on hard impact with an object underwater such as a rock in shallow lake waters or hard ground, the invention could be made such that the keel plates or planar members  76  are detachable for replacement without the necessity of replacing the portion  62  that is attached to the directional nozzle  18 . 
     Some jet skis do not have a cover or hood  16  in combination with the directional nozzle  18 . In a further embodiment to accommodate this type of personal watercraft  12 , the auxiliary keel system, which is depicted generally as  10   b  in FIGS. 3 a - 3   f  comprises a generally C-shaped portion  94  having means  96  for attaching the C-shaped portion  94  to an outside lower surface  98  of the directional nozzle  18 . 
     A generally planar keel member  100  angularly depends from a location near each of a first end  102  and a second end  104  of the C-shaped portion  94  so that a distance  106  between a lower edge  110  of each planar keel member  100  is greater than another distance  108  between the locations from which the planar keel members  100  depend from the C-shaped portion  94 . 
     As with the previously described embodiments, when the directional nozzle  18  moves, the planar keel members  100  move in unison with the directional nozzle  18  to provide enhanced steering performance. 
     It is preferred that the means  96  for attaching the C-shaped portion  94  to the outside lower surface  98  of the directional nozzle  18  further includes at least two apertures  112  in the C-shaped portion  94  for inserting means  86   a  for fixedly engaging the C-shaped portion  94  to the outside lower surface  98  of the directional nozzle  18 . 
     As with the previously described embodiment, it is preferable that each planar keel member  100  has a generally tapered arcuate-shaped front edge  114 , that is, the edge which is nearest the stern  12   a  of the watercraft  12  when installed. 
     Additionally, as with the previous embodiment, another optional feature is the incorporation of means  116  for detachably connecting each planar keel member  100  to the generally C-shaped portion  94 . This allows for cost efficient replacement of any broken keel plate  100  made from plastic or other polymeric materials. 
     As with any of the above described embodiments, the invention can be made from several materials, including steel, aluminum, polymeric materials including reinforced composites. One skilled in the art can determine the thickness required and the overall size depending on the application and expected hydraulic forces. 
     As previously stated above in where the drawings are briefly described, FIG. 3 c  is a depiction of the invention of either FIG. 3 a  or FIG. 3 b  attached to the directional nozzle of a jet ski. As the nozzle moves, the auxiliary keel system moves in unison to provide enhanced positive stability and steering control of the jet ski. Now referring to FIGS. 3 d - 3   f , FIG. 3 d  is a representation of the invention of FIGS. 3 a  or  3   b  attached to a jet ski with the normal forward movement water line and the keel members submerged below the water line. FIG. 3 e  depicts the jet ski leaning to the starboard to initiate a right turn and the lowered right side keel member provides control assistance to the operator. As the watercraft straightens out and proceeds to a high speed, FIG. 3 f  demonstrates that the keel members typically remain at least partially below the water line, despite the fact that the nozzle itself may rise somewhat above the water line. The submerged keel members enables the operator to maintain turn control at high speeds. 
     FIG. 4 depicts another embodiment wherein the keel system or keel members  76  described above is incorporated directly into the manufacture of a directional nozzle  18 . FIGS. 5 a - 5   c  and  6   a - 6   c  depict conceptually that single keel system where the keel member  76  depends essentially parallel to the center of the directional nozzle  18  to a two keel system to a combination of both embodiments for a three keel system. The difference being that the keel system depicted in FIGS. 5 a - 5   c  is integrally incorporated into the manufacture of a directional nozzle  18  while in the depiction of FIGS. 6 a - 6   c , the keel members  76  are detachably engaged with the directional nozzle  18 , that is, the directional nozzle attachment portion (also referred to herein before as a C-shaped attachment portion) is adapted to fit over the lower outside surface of the directional nozzle  18 . Where the keels are integrally formed with the nozzle, the keels can be welded to the nozzle or molded as part of the nozzle fabrication. 
     To elaborate on the above-described embodiments depicted in FIGS. 5 a - 5   c  and  6   a - 6   c , a single keel would provide positive steering at a slow speed and reduce its steering influence as the watercraft tilts into a high speed turn. Two angled keels would provide more steering influence at high speed for precise maneuvering. The three keel system would provide continuous steering influence regardless of the velocity or attitude or pitch of the watercraft. These variations would provide a wide range of assistance levels to meet particular needs of the watercraft operator and allow them to tailor make an auxiliary steering system of their preference. 
     Generally speaking, most nozzle have a taper to them and the C-shaped attachment portion (or directional nozzle attachment portion) is accordingly adapted to account for the taper. Other nozzle may have irregular shapes in the sense that a portion such as the lower portion may have a rounded or ellipsoidal shape and the upper part may have a polygonal portion. In all cases the attachment portion of the keels would merely be adapted to fit against the surface. 
     For safety purposes, the bottom edges of the keels are preferably rounded off as shown in FIGS. 7 a - 7   b  and  8   a - 8   b , numerals  120   a  and  120   b  respectively, with a radius of at least {fraction (3/16)} inch. This feature can also be included by gradually tapering the keels to widen at the bottom edges to accommodate the rounded bottoms as shown in FIGS. 8 a  and  8   b.    
     In addition, in circumstances where the keel member are designed to be part of the directional nozzle, then the tapered keel may be hollow (see  122  in FIGS. 12 a  and  12   b ) such that a portion of the outlet flow of water can also be directed through the hollow portion  122  of the keel members and exit the back edge of the keel members in a substantially parallel direction to the general flow of the water out the directional nozzle. Otherwise, the keel members may be solid as shown as  124  in FIGS. 11 a  and  11   b.    
     As an example of another way of providing for a rounded bottom edge, different than that depicted in the drawings, the fins or keel members directly mounted to the directional nozzle, can be straight and tapered up to the front of the directional nozzle. The leading edge may be flat inside and slightly rounded on the outside for safety reasons discussed above. The rounded portion can be gradual so as to disappear toward the front for less drag. 
     The surfaces of the directional nozzle that would normally be convex on either exterior side of the fins and between the fins can instead be concave and gradually blend into the nozzle body toward the front. See FIGS. 13 a  and  13   b  further described below. This concave design will increase the effect for both high and low speed steering by cupping the water. It will also add to a faster planing during acceleration from an idle speed and lessen high speed hopping (tendency of bow to rise up and drop down) by capturing the passing water and forcing the rear of the watercraft upwardly. Cupping the side of the directional nozzle between the formed ridges  128  and keel members gives extra control for side to side movement. 
     If more positive reaction to steering is desired or even less positive reaction to steering is desired, than that obtained through the contemplated 1:1 response in the embodiment using tie rods described above, an odd number of apertures ( 126   a ,  126   b ), linearly arranged where the tie rod ends are connected together could be provided so that an owner can adjust the sensitivity of the steering response by connecting the tie rod ends to the central aperture for an essentially 1:1 response, to an aperture closer to the stern for a little less rapid and lesser response (less than 1:1) and to an aperture further away for a more rapid and greater response (greater than 1:1). FIG. 9 depicts such an embodiment to hardware similar to that described in FIG. 1 e . The additional apertures allows the operator to increase or decrease the travel of the keels in proportion to the travel of the nozzle. The further you go the greater the travel related to the keels. The embodiment depicted in FIG. 9 is also depicted in FIG. 10 as a universal steering mount that bolts to assorted jet nozzles and clears any reverse hoods while it operates the tie rods. 
     FIGS. 13 a  and  13   b  are schematic depictions of another embodiment wherein two or more keel members can be incorporated into a directional nozzle with a ridge  128  being formed along either side of the directional nozzle so as to form cupped sides  130  between each outside keel member and the ridges  128 . It is also preferred, but not necessary, that a longitudinal tapered inverted cup-shape  132  be formed on the directional nozzle between the keel members as well. Where the outside keel members depend relatively straight down from the directional nozzle, it is recommended that the most bottom ends  134  of each outside keel member (when two or three keel members are included) be formed to bow or slightly bend outwardly. The benefits for providing these inventive features is discussed above. 
     It should be understood that the preceding is merely a detailed description of one or more embodiments of this invention and that numerous changes to the disclosed embodiments can be made in accordance with the disclosure herein without departing from the spirit and scope of the invention. The preceding description, therefore, is not meant to limit the scope of the invention. Rather, the scope of the invention is to be determined only by the appended claims and their equivalents. 
     Now that the invention has been described,