Patent Publication Number: US-11649019-B2

Title: Navigational running light retrofit system

Description:
CROSS-REFERENCE TO OTHER APPLICATIONS 
     This application claims priority to, and the benefit of, U.S. Provisional Patent Application No. 63/047,666, filed Jul. 2, 2020 with the U.S. Patent Office, which is incorporated by reference. 
    
    
     FIELD OF INVENTION 
     The present invention relates to an efficient and cost-effective means to retrofit a navigational running light fixture with an LED (light emitting diode) light source, such as those used specifically on ships of the United States Navy. 
     BACKGROUND OF THE INVENTION 
     Each ship of the United States (U.S.) Naval fleet requires a specific set of navigation lights known as “running lights”. A running light set, typically consists of (5) five light fixtures, namely, forward masthead, aft masthead, port side, starboard side, and stern light fixtures. Each vessel must operate this set of running light fixtures from dusk until dawn without exception. The design and manufacture of each running light fixture is unique to the U.S. Navy. The requirements for the individual running light fixtures are called out in publicly available military specifications. Each running light fixture utilizes a dual filament incandescent lamp. If a lamp filament fails, a crewmember must replace the lamp as soon as there is a safe opportunity to do so. The incandescent lamps have a typical operational life expectancy of &lt;1,200 hours, as they are under constant vibration and are regularly subjected to mechanical shock. Crewmembers replace these lamps with high frequency. Ships installed with the U.S. Navy specified running lights will continue to replace incandescent lamps and repair existing lighting equipment, until the U.S. Navy mandates replacement/upgrade of the fixtures from the incandescent light source to a light emitting diode (LED) source. As there is no mandate, in addition to the fact that the existing navigational running light fixtures continue to meet the current requirements, active ships of the U.S. Naval Fleet will continue to use the incandescent light source technology for the foreseeable future. 
     As a contemplated precursor for the present invention, the present inventors have contemplated replacing each of the running light fixtures, with entirely new light fixtures utilizing an LED light source. The new LED running light fixtures would allow continuous operation of the running light fixtures set without failure for several years. The main shortcoming of this contemplated precursor is that the removal and replacement of the legacy running light fixtures, in their entirety, requires extensive manpower, new hardware (mechanical and electrical), scaffolding, crane rental and typically extensive paperwork for the removal of equipment from the ship&#39;s exterior. Complete replacement of a legacy running light set is therefore both cost and logistically prohibitive. 
     As a contemplated precursor for the present invention, the present inventors have also contemplated replacing the incandescent lamp of the running light fixtures with an LED lamp equivalent. The main shortcoming of this contemplated precursor is that all of the electronics, required to comply with strict U.S. Naval requirements for ship&#39;s power, electromagnetic (EMI) emissions, and mechanical shock, must fit within the envelope of the existing incandescent lamp. In addition to meeting the said U.S. Naval requirements, this contemplated LED lamp equivalent must also provide a heat source to de-ice the face of the running light in extreme cold environments. The heat source described is required to mimic the waste heat output of the incandescent lamp, which is a minimum of 25 Watts. Development of an LED lamp to meet these requirements is cost prohibitive and may not be possible with the current technology available today. 
     It would be desirable to provide an efficient and cost-effective solution for upgrading existing incandescent running light fixtures with LED light sources, on all active U.S. Navy ships, all U.S. Coast Guard ships, or any other boat, ship, or vessel. 
     SUMMARY OF THE INVENTION 
     The present invention provides a retrofit system for a navigational running light fixture to replace the existing incandescent light source with an LED light source (where “LED light source” and “LED light” are used interchangeably herein). The retrofit system uses mechanical constraints that cooperate in a novel way to provide and maintain proper location, alignment, mounting and sealing of an LED light within a navigational running light fixture. The navigational running light fixtures are currently installed and are required on all ships of the U.S. Naval fleet. These retrofit systems and method of retrofitting, and other apparatus and methods described herein, may be used to retrofit incandescent light fixtures on other boats, ships, and vessels other than those associated with the U.S. Navy. 
     An exemplary retrofit system provided by the present invention includes a novel positioning tube component with geometry that cooperates with an existing navigational running light fixture to align and position the retrofit system. The positioning tube provides features that allow installation of a sealing component that is in turn secured and seated by a securing ring component of the navigational running light fixture being retrofit. The positioning tube further provides features that align and secure a navigational LED light. 
     The LED light may be a commercially available product that has been modified to function within the retrofit system, or a custom or newly manufactured LED light may be provided to incorporate the modifications or features formed into the commercially available LED light. Threaded holes are added to the commercially available LED light to allow mounting of a novel stabilizer plate onto the top surface of the LED light. A stabilizer plate may be included with the retrofit system to maintain position and structural integrity of the retrofit system when subjected to extreme mechanical shock and vibration conditions experienced by the navigational running light fixtures. 
     The present invention also provides a method of installing the navigational running light retrofit system into an existing navigational running light fixture currently utilized on the boats, ships, and vessels, such as those of the U.S. Naval fleet. The method includes steps of (a) disassembling and removing components of the navigational running light fixture; (b) installing a positioning tube and seal; and (c) mounting the stabilizer plate to the LED light while aligning and securing the LED light to the positioning tube. A corresponding retrofit system (a retrofit kit) is also described herein, which may be used to practice any such method described herein. 
     One advantage provided by the retrofit system is that the existing navigational running light fixtures will not be removed from the US Navy ship. Therefore, all existing mounting means, hardware and electrical cabling will be left intact. There is no expense for replacing the existing fixtures with new mounting hardware (mechanical or electrical), scaffolding or cranes. Approval for the removal of equipment from the ship&#39;s exterior will not be required. With the significant reduction in manpower, cost and logistics, the retrofit system is a cost-effective means to convert the existing incandescent running light fixtures to an LED light sources such as those on all ships of the U.S. Naval fleet. 
     Another advantage of the retrofit system is that every ship (combatant and support type) of the U.S. Naval fleet utilizes the same running light fixtures. The speed at which the retrofit system can be deployed is similar to that of a crew member replacing a failed lamp in an existing running light fixture. Therefore, the entire US Naval fleet may be retrofit (upgraded to an LED light source) using this retrofit system while in port, as opposed to waiting for the ship to go into drydock or into a maintenance period. Therefore, adoption of the retrofit system at the ship level across the entire fleet is achievable. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    is an isometric exploded view of an exemplary navigational running light retrofit system in accordance with the invention. 
         FIG.  2   a    is an isometric view of an exemplary positioning tube; and  FIG.  2   b    is an enlargement of the encircled area of  FIG.  2   a    labeled  FIG.  2     b.    
         FIG.  3   a    is an isometric view of a commercially available LED running light;  FIG.  3   b    is a side view of  FIG.  3   a   ; and  FIG.  3   c    is an enlargement of the encircled area of  FIG.  3   b    labeled  FIG.  3     c.    
         FIG.  4    is an isometric view of an exemplary stabilizer plate. 
         FIG.  5   a    is an isometric view of a legacy navigational running light fixture; and  FIG.  5   b    is an exploded isometric view of  FIG.  5     a.    
         FIG.  6   a    is an isometric view of a legacy navigational running light fixture that has been retrofit with an exemplary retrofit system;  FIG.  6   b    is an exploded isometric view  FIG.  6     a.    
         FIG.  7   a    is an isometric view of the positioning tube, seal and securing ring being installed into a legacy navigational running light fixture. The lighting base has been partially cutaway to expose the boss geometry within; and  FIG.  7   b    is an enlargement of the encircled area of  FIG.  7   a    labeled  FIG.  7     b.    
         FIG.  8   a    is an isometric view of the positioning tube and seal fully installed into a legacy navigational running light fixture, partially cutaway to show the relative position and interaction with the legacy base component and sealing ring; and  FIG.  8   b    is an enlargement of the encircled area of  FIG.  8   a    labeled  FIG.  8     b.    
         FIG.  9    is an isometric view of the LED light being installed into a legacy navigational running light fixture with positioning tube and seal in place and secured. 
         FIG.  10   a    is an isometric view of the LED light fully installed into a legacy navigational running light fixture. The top of the running light fixture has been partially cutaway to show the relative position; and  FIG.  10   b    is an enlargement of the encircled area of  FIG.  10   a    labeled  FIG.  10     b.    
         FIG.  11    is an isometric view of the fully installed retrofit system into a legacy navigational running light fixture. The top of the running light fixture has been partially cutaway to show the relative position of the assembly and interaction of the stabilizer plate to the fixture housing. 
         FIG.  12   a    is a front view of the retrofit system fully installed into a legacy navigational running light fixture;  FIG.  12   b    is a section view of  FIG.  12   a    taken at Arrows  FIG.  12   b   - FIG.  12   b   ; and  FIG.  12   c    is an enlargement of the circle portion of  FIG.  12   b    labeled  FIG.  12     c.    
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following detailed description will proceed with reference to a particular, illustrated embodiment. However, the embodiment shown in the drawings is exemplary of the claimed subject matter, and should not be used to limit the scope of the invention, but rather to cover all variations and modifications obvious to a person of ordinary skill in the art. 
     The navigational running light retrofit system of  FIG.  1    was a consideration of the inventors in developing the presently claimed invention, and by itself is not believed to constitute prior art. 
     This description includes features relating to (1) a navigational running light retrofit system, (2) a navigational running light fixture currently in use and specified by the US Naval fleet, and (3) a typical installation of the retrofit system into a navigational running light fixture. 
     Navigational Running Light Retrofit System 
     With reference to  FIG.  1   , a navigational running light retrofit system  10  in accordance with an exemplary embodiment of the invention includes: a positioning tube  22 , a positioning screw  24 , a seal  26 , an LED light  28  (which is also referred to herein as an “LED navigational running light”), a stabilizer plate  30 , and threaded fasteners  32 . 
     The positioning tube  22  is shown in  FIG.  2   a    as an isometric view. In this particular embodiment of the positioning tube, an inner cylindrical side defined by an internal diameter is shown with a radial helix geometry  34  protruding from the inner cylindrical side and a corresponding surface. In other words, this radial helix geometry forms an elongate protrusion extending in a helical direction but which forms only a portion of a helix, such as, for example, a segment that extends approximately 90 degrees around the inner diameter, such as to form a portion of a thread. The radial helix geometry  34  of this embodiment will allow attachment and sealing of an exemplary LED light  28  to the positioning tube  22 . The radial helix geometry may be molded, machined, or otherwise formed along the inner cylindrical side using any known manner. The radial helix geometry is arranged along two substantially equal and opposite sections along the cylindrical inner tube side, although other configurations and arrangements may be employed so long as achieving the purpose of receiving and securing an LED light. Further, the inner cylindrical side of the positioning tube  22  may be constructed with various types of fastening geometry to accommodate alternate styles and manufacturers of LED lights, whether such geometry is a protrusion or a recess. To present some examples, the inner cylindrical side of the positioning tube  22  may be constructed with a fully threaded surface or with bayonet type receiver geometry to attach the LED lights of other manufacturers. A positioning notch  36  has been added to the top surface of the positioning tube  22  to provide a visual means for aligning the positioning tube  22  within a navigational running light fixture. A threaded hole  40  with a concentric flat surface  38  is constructed into the stepped outer diameter (outer surface) of the positioning tube  22  as shown in  FIG.  2   b   . The threaded hole  40  is required to accommodate the positioning screw  24 . The concentric flat surface  38  is of sufficient depth and diameter to allow the head of positioning screw  24  to rest in full contact against the concentric flat surface  38  once the positioning screw  24  is threaded fully into the positioning tube  22 . The threaded hole  40  does not break through to the inner cylindrical side of the positioning tube  22  in order to maintain a water-tight seal of the navigational running light retrofit system  10  upon final installation into a navigational running light fixture. Also shown in  FIG.  2   a    are a plurality of notches  42 , and more specifically three (3) substantially equally spaced notches  42  at the base of the positioning tube  22  which are of sufficient width and depth to accurately position and resist and even substantially prevent the rotation of the positioning tube  22  within the navigational running light fixture. It is contemplated that the plurality of notches  42  may include more or less than three (3) notches. Notches  42  are also referred to herein as locating elements, which may comprise any other feature in lieu of notches. The positioning tube  22  is constructed from a rigid material, such as metal or a structurally stable polymer, and must maintain corrosion resistance in an extreme marine environment. 
       FIG.  3   a - 3   c    show an LED light  28 , used in an embodiment the navigational running light retrofit system  10 . The LED light  28  is a commercially available LED type navigational light meeting the requirements of the US Coast Guard regulations for navigational running lights. Such an LED light is sold, for instance, by Lopolight ApS of Humlebaek, Denmark, as Part No. 300-138 (masthead light) or Part No. 301-108 (starboard sidelight) or Part No. 301-109 (port sidelight) or Part No. 301-105 (stern light). The LED light  28  is modified from its commercially available form, or may be manufactured originally, to include at least two equally spaced threaded holes  44 , as shown in  FIG.  3   a   . The threaded holes  44  are used to fasten the stabilizer plate  30  to the top surface of the LED light  28 , although other means or mechanisms may be employed on other embodiments for attaching stabilizer plate to the top surface of the LED light. In this particular embodiment, the LED light  28  is constructed with radial helix geometry  50  which has been machined into two substantially equal and opposite sections to form a recessed elongate feature extending helically in a radial direction, that is, extending in a helical direction but which forms only a portion of a helix, such as, for example, a segment that extends approximately 90 degrees around the inner diameter, such as to form a portion of a thread. This radial helix geometry  50  allows attachment and sealing of the LED light  28  to the positioning tube  22  by way of mating with radial helix geometry  34  of said tube  22 . It is contemplated that feature  34  may instead form a recess and feature  50  from a protrusion. Moreover, while there is two (2) of each feature  34  and feature  50  forming corresponding pairs of one another configured in mating fashion, it is contemplated that additional pairs of mating features  34 ,  50  may be provided in other variations.  FIG.  3   c    shows an O-ring seal  48  which is installed at the base of each LED light  28 . The O-ring seal  48  is also required to create and maintain a water-tight seal between the LED light  28  and the positioning tube  22  upon installation of the retrofit system into a navigational running light fixture.  FIG.  3   c    also shows a circular positioning notch  46  located on the lower outer diameter, that is, the lower outer cylindrical side, of the LED light  28 . The positioning notch  46  is formed at substantially the same diameter and at substantially the same depth as the concentric flat surface  38  of the positioning tube  22 . Once the position notch  46  is aligned and concentric with the concentric flat surface  38  of the positioning tube  22 , the head of positioning screw  24  is allowed to seat flat against both the LED light  28  and positioning tube  22 . The positioning notch  46  has a radial location on the outer diameter of the LED light  28  that specifically positions the LED light  28  to the positioning tube  22 , in cooperation with the fully installed positioning screw  24 . 
       FIG.  4    shows an exemplary stabilizer plate  30  having at least two diametrically opposed finger holes  52  of sufficient size to allow the user to rotate the stabilizer plate  30  into position on the top surface of the LED light  28 , during the installation of navigational running light retrofit system  10 . In other variations, any other quantity of finger holes  52  may be provided. In the alternative, other features, such as any recess or protrusion, may operate as a substitute for any finger hole. The stabilizer plate  30  also provides at least two through holes  54  to allow for the insertion of threaded fasteners  32  of  FIG.  1    which are required to secure the stabilizer plate  30  to the LED light  28 . It is contemplated that any other quantity of fasteners  32  and corresponding holes  54  may be employed in other variations. Additionally, any other means or mechanism may be used in lieu of fasteners  32  and holes  54 , such as adhesive or weldments, for example. These through holes  54  are diametrically opposed but may be of any other configuration or arrangement to achieve their stated purpose. The stabilizer plate  30  is of sufficient outer diameter to allow no more than ⅛″ (0.125 inch) gap between the diameter of the stabilizer plate  30  and the inner diameter of the upper housing of the navigational running light fixture. The relationship between these diameters will be become apparent in further figures of the detailed description. The stabilizer plate  30  is constructed from a structurally rigid material, such as a metal or rigid polymer, and will maintain corrosion resistant in extreme marine environments. 
     Navigational Running Light Fixture (Currently in Service and Specified by the U.S. Naval Fleet) 
       FIG.  5   a    shows an isometric view of a navigational running light fixture  60 . These running light fixtures are currently being utilized on every ship of the US Naval fleet.  FIG.  5   a    is a representation of one of six navigational light fixture variants that may be retrofit with the navigational running light retrofit system  10 . The military part numbers for each of the six navigational light fixtures are indicated in U.S. military specification sheet(s) MIL-L-24560/8, MIL-L-24560/9, and MIL-L-24560/10; whereas sheet MIL-L-24560/8 specifies navigational stern light fixtures, clear (SYM 196.3), blue (SYM 196.4) and yellow (SYM 197.2) variants; whereas sheet MIL-L-24560/9B specifies navigational side light fixtures, port side red (SYM 182.2) and starboard side green (SYM 183.2) variants; whereas sheet MIL-L-24560/10 specifies the navigational masthead light fixture (SYM 172.2). There is no single manufacturer for these light fixtures. Any manufacture may build the navigational running light fixtures, or the individual components of running light fixtures, to said specifications and seek approval to supply the U.S. Navy with these fixtures for shipboard use. All referenced military specification sheets are hereby incorporated herein by reference. 
       FIG.  5   b    is an isometric exploded view of the navigational running light fixture  60 . Each navigational running light fixture  60  is composed of components ( 62  through  76 ). The differential between the six running light fixture variants is the color of the glass globe  72  and the angle of the wing like features (specifically know as side screens) of the running light fixture housing  64 . 
     A molded plastic lighting base  62  is attached to the fixture housing  64 . The lighting base  62  is a common component on all six navigational running light fixtures variants. The lighting base  62  is indicated in U.S. military specification sheet MIL-L-24560/2; U.S. military part number M24560/2-010; National Stock Number (NSN) 6220-01-185-5545. The fixture housing  64  is a fabricated aluminum assembly which includes; a housing portion, base plate and side screens. The requirements for the fabrication and dimensions of the fixture housing  64  are specified in U.S. military specification sheet(s) MIL-L-24560/8, MIL-L-24560/9, and MIL-L-24560/10. 
     A lamp holder  66  is attached within the lighting base  62 . The lamp holder  66  is specified in U.S. military specification sheet MIL-L-970; U.S. military part number M970/6; National Stock Number (NSN) 6250-00-939-8126. The lamp holder  66  is required to hold a lamp  68 . The lamp  68  is a commercially available incandescent type, dual filament; industry part number 50/50T12. 
     The navigational running light fixture  60  also includes a gasket  70  that is placed onto the top of the base  62 . The glass globe  72  is then placed over the lamp and onto the gasket  70 . The securing ring  74  is then installed over the globe  72  and threaded to the base  62 . The securing ring  74  is indicated in U.S. military specification sheet MIL-L-24560/2; U.S. military part number M24560/2-011; National Stock Number (NSN) 6220-01-225-6073. The final component to be described is the fixture housing cover  76  which is placed onto the fixture housing assembly  62  and secured with quarter-turn wing nuts as shown. 
     Installation of the Retrofit System into a Navigational Running Light Fixture 
       FIG.  6   a    shows a navigational running light fixture that has been retrofit with the navigational running light retrofit system  10 . We will refer to the fully retrofit navigational running light fixture assembly as  80 .  FIG.  6   b    is an isometric exploded view of the navigational running light fixture assembly  80  retrofit with the navigational running light retrofit system  10 . This exploded view shows the sequence in which the components ( 22  through  32 ) of the retrofit system  10 , in cooperation with the components of the existing navigational running light fixture, will be installed. 
     During the installation of the navigational running retrofit system  10 , the lamp holder  66 , lamp  68 , gasket  70  and globe  72  are removed from the legacy navigational running light fixture  60  (referenced in  FIG.  5   a   ) and further discarded. It is important to note that ship&#39;s personnel may safely access these running light fixtures to replace the lamp holder  66 , lamp  68 , gasket  70  and globe  72 , without the use of lift equipment and can complete these maintenance tasks in a timely manner while at sea. Removal of a complete navigational running light fixture  60  from the ship structure is not possible without the use of lift equipment, additional manpower, new hardware and additional safety equipment. Further, the removal of a complete navigational running light fixture cannot be performed while at sea. The navigational running retrofit system  10  is the only known novel means to upgrade the legacy navigational running light fixture with an LED light source without replacement of the entire fixture. 
     Refer now to  FIG.  7   a   - FIG.  8   b    for the next detailed description of the installation process. After removal of the above stated components from the legacy navigational running light fixture, the positioning tube  22  is then inserted into the lighting base  62 . The positioning notch  36  should be positioned towards the bow of the ship or 0° (DEG). This step is critical for the eventual alignment and direction of the light leaving each specific navigational running light fixture. The seal  26  is then placed onto the stepped diameter of the positioning tube  22 . The internal diameter defining the inner cylindrical side, of the seal  26  is sized slightly under the outer diameter defining the outer cylindrical side of the positioning tube  22  whereby causing a radial seal to the positioning tube  22 . The securing ring  74  is then threaded onto the lighting base  62 , whereby securing the positioning tube  22  and seal  26  to the lighting base  62 . The seal  26  is shown with a round cross section, but may also be molded into various cross sections to cause a water tight seal between the positioning tube  22  and the lighting base  62 . 
     As shown in  FIG.  8   a - 8   b   , the positioning tube  22  is of such outer diameter to allow its insertion into the lighting base  62  while also allowing the seal  26  to compress on both the upper surface of the lighting base  62  and the stepped surface of the positioning tube  22  when the securing ring  74  is fully threaded onto the lighting base  62 . The enlarged section view  FIG.  8   b   , shows one of the three notches  42  of the positioning tube  22  positioned over one of the three bosses  78  at the lower floor of the lighting base  62 . The notches  42  are sized and spaced to position around the bosses  78 , whereby radially positioning the navigational running light retrofit system in a specific relationship to the navigational running light fixture. The notches  42  are also required to prevent the positioning tube  22  from any rotation after installation. Notches  42  are more broadly referred to as positioning elements and bosses  78  are more broadly referred to herein as lower positioning elements. It is understood that positioning elements and lower positioning elements may each comprise other features. 
       FIG.  9    shows the insertion of the exemplary LED light  28  through the top opening of the running light fixture housing  64 . It is at this point in the installation process that the electrical connection between the LED light  28  and the existing power cable of the navigational running light fixture is made. After electrical connection is complete, the LED light  28  is positioned so that the radial helix geometry  50  is clocked 90° (DEG) from the helix geometry  34  of the positioning tube  22 . 
     Once the LED light  28 , as shown in  FIG.  10   a    is seated into the positioning tube  22 , the LED light  28  is to be rotated clockwise until the positioning notch  46  is aligned and concentric with the concentric flat surface  38  of the positioning tube  22 .  FIG.  10   b    shows an enlarged view of this alignment. It is important to note that the embossed arrow on the top surface of the LED light  28  should be pointing towards the bow of the ship or 0° (DEG), regardless of the navigational running light fixture variant (masthead, side or stern light). 
     The positioning screw  24  is now threaded into the threaded hole  40  of the positioning tube  22 .  FIG.  11    shows the positioning screw  24  installed into the retrofit navigational running light fixture assembly  80 . The stabilizer plate  30  is placed through the top of the navigational running light fixture housing  64  and positioned on the top surface of the LED light  28 . Using the finger holes  52  of the stabilizer plate  30 , the plate can be rotated until the threaded fasteners  32  can be inserted and threaded into the LED light  28 .  FIG.  11    also shows a partial cut away view of the upper housing  64  in order to show the relative position of the stabilizer plate  30  and the minimal gap between the outer diameter of the stabilizer plate  30  and the inner diameter of the upper portion of the navigational running light fixture housing  64 . This gap must be less than 1/16″ (0.062 inches) to maintain stability of the retrofit system under extreme mechanical shock, in which the retrofit system will experience shipboard. 
       FIG.  12   a    shows a front view of the fully retrofit navigational running light fixture assembly  80 . The fixture housing cover  76  is now in place and secured. A cross section of the assembly, as shown in  FIG.  12   b   , allows a view of the interaction between; the radial helix geometry  50  of the LED light  28 , the O-ring seal  48  of the LED light  28 , and the radial helix geometry  34  of the positioning tube  22 . An enlarged view of this interaction is also shown in  FIG.  12   c   . The surface of the helical geometry cooperates to pull the mating surfaces of the LED light  28  and the positioning tube  22  together upon clockwise rotation. The O-ring seal  48  is now compressed on four surfaces to cause a water-tight seal. 
     The navigational running light retrofit system  10  is now positioned, secured, and sealed using the components and structural elements of the existing navigational running light fixture. The navigational running light retrofit system  10  cooperates with the components and structural elements in a novel way to allow the light to be emitted from the LED light  28  to exit from the retrofit navigational running light fixture assembly  80  in the required angular direction, for each of the specific navigational running light fixture variants. 
     Certain embodiments of the navigational running light include the following:
         (1) In a first embodiment, a navigational running light retrofit system for changing an incandescent light source to an LED light source, comprises:
           a) an LED navigational running light that has been modified from its commercial form to cooperate with the elements of the retrofit system as described herein;   b) a stabilizer plate for maintaining structural stability of the retrofit system as described herein;   c) an O-ring seal for arrangement between the LED light and a positioning tube;   d) a positioning screw;   e) a positioning tube having one or more locating elements that cooperate with the locating elements of the modified LED navigational running light to locate the positioning tube relative to the modified LED navigational running light, the locating elements of the positioning tube and the locating elements of the modified LED navigational running light each forming mechanical constraints to align and maintain alignment of the retrofit system for maintaining the desired direction and angle of an incandescent light exiting the navigational running light fixture for retrofit.   
           (2) In another embodiment of the navigational running light retrofit system according to the first embodiment under (1) the stabilizer plate is of similar diameter or of substantially the same diameter of the internal surface of the upper housing, such as of a U.S. Naval running light fixture as specified in U.S. military specification sheets MIL-L-24560/8, MIL-L-24560/9, and/or MIL-L-24560/10, each of which are hereby incorporated herein by reference.   (3) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) or (2) above, the stabilizer plate has one or more through holes to allow assembly to the modified LED navigational running light using mechanical fasteners as described herein.   (4) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (3) above, the stabilizer plate has one or more through holes to be used as finger holes that facilitate positioning on the top surface of the modified LED navigational running light as described herein.   (5) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (4) above, the LED navigational running light has been modified to cooperate and align with the positioning tube, positioning screw, and stabilizer plate as described herein.   (6) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (5) above, the positioning tube includes three lower positioning elements that cooperate with the internal features of the lighting base, such as is specified in U.S. military specification sheet MIL-L-24560/2 and/or U.S. military part number M24560/2-010, each of which are hereby incorporated herein by reference.   (7) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (6) above, the positioning tube having a first outer cylindrical surface defined by a first outer diameter to allow insertion into the inner diameter of the lighting base, such as is specified in U.S. military specification sheet MIL-L-24560/2 and/or U.S. military part number M24560/2-010.   (8) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (7) above, the positioning tube has a second outer cylindrical surface defined by a second outer diameter to allow insertion into the inner diameter of the securing ring, such as is specified in U.S. military specification sheet MIL-L-24560/2 and/or U.S. military part number M24560/2-011, which is hereby incorporated herein by reference.   (9) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (8) above, the positioning tube has a step height between the first and second outer diameters which allow the compression of a seal between the surfaces of the securing ring, lighting base, and positioning tube.   (10) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (9) above, the positioning tube being constructed with geometry on the inner cylindrical surface to allow the positioning and securing of an LED navigational running light to the top surface of the position tube.   (11) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (10) above, the positioning tube having a single threaded hole on the second outer diameter to allow insertion of a positioning screw.   (12) In another embodiment of the navigational running light retrofit system according to any embodiment under (1) to (11) above, a positioning screw has a sufficient head diameter and height is configured to cooperate with elements as described herein of both the positioning tube and the modified LED navigational running light in tandem to form a mechanical constraint to align and maintain alignment between the positioning tube and the modified LED navigational running light.       

     Certain embodiments of the method of retrofitting a navigational running light fixture described herein include the following:
         (1) A method of installing a navigational running light retrofit system as set forth herein, comprising of steps of:
           (a) removing existing components from a navigational running light fixture being retrofit;   (b) installing the positioning tube component into the lighting base of the running light fixture being retrofit;   (c) installing the seal using the securing ring of the running light fixture being retrofit;   (d) installing a modified LED navigational running light to the positioning tube; and   (e) installing a stabilizer plate to the modified LED navigational running light.   
               

     While various improvements have been described herein with reference to particular embodiments thereof, it shall be understood that such description is by way of illustration only and should not be construed as limiting the scope of any claimed invention. Accordingly, the scope and content of any claimed invention is to be defined only by the terms of the following claims, in the present form or as amended during prosecution or pursued in any continuation application. Furthermore, it is understood that the features of any specific embodiment discussed herein may be combined with one or more features of any one or more embodiments otherwise discussed or contemplated herein unless otherwise stated. 
     To the extent used, the terms “comprising,” “including,” and “having,” or any variation thereof, as used in the claims and/or specification herein, shall be considered as indicating an open group that may include other elements not specified. The terms “a,” “an,” and the singular forms of words shall be taken to include the plural form of the same words, such that the terms mean that one or more of something is provided. The terms “at least one” and “one or more” are used interchangeably. The term “single” shall be used to indicate that one and only one of something is intended. Similarly, other specific integer values, such as “two,” are used when a specific number of things is intended. The terms “preferably,” “preferred,” “prefer,” “optionally,” “may,” and similar terms are used to indicate that an item, condition or step being referred to is an optional (i.e., not required) feature of the embodiments. Ranges that are described as being “between a and b” are inclusive of the values for “a” and “b” unless otherwise specified.