Abstract:
An apparatus, system, and method are disclosed for a collapsing approach ski for maneuvering over terrain in a climbing and sliding fashion, with a traction component operative below the sliding surface on the underside of the ski to facilitate climbing uphill without substantially interfering with sliding downhill. It combines the advantages of a snowshoe, including a large surface area, a toe cleat that claws into the terrain and a lifting of the front tip with each step, with the advantages of an approach ski, including a fibrous skin for added traction climbing uphill and an ability to slide down hill. A stretchable portion in the skin adjacent to a hinge in the ski permits the ski to be compactly collapsed without removing the skin, for easy packing and storage while not in use. For climbing up a steep incline, a removable fixed cleat provides added traction, and a heel riser reduces the strain on the lower leg and Achilles tendon region of the skier.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of and claims priority to U.S. Provisional Patent Application No. 60/885,901 entitled “PIVOTAL SKI CLEAT SYSTEM AND APPROACH SKI SYSTEM” and filed on Jan. 21, 2007 for Lane A. Ekberg, to U.S. Provisional Patent Application No. 60/888,700 entitled “FOLDING APPROACH SKI SYSTEM” and filed on Feb. 7, 2007 for Lane A. Ekberg, and to U.S. Provisional Patent Application No. 60/894,541 entitled “FOLDING SKIS FOR PACKS AND SNOWMOBILES AND AN ADJUSTABLE MOUNTING PLATE FOR FOOTWEAR” and filed on Mar. 13, 2007 for Lane A. Ekberg, which are all incorporated into this document by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to winter sports equipment and more particularly relates to an approach ski. 
         [0004]    2. Description of the Related Art 
         [0005]    Approach skiing as well as snowshoeing are popular winter sports that provide backcountry exploration, exercise, and entertainment. Unlike a conventional alpine ski which is intended for downhill skiing, an approach ski may be equipped to climb as well as slide. In a single day snowshoers and ascending skiers travel to their various destinations, each having problems with their particular travel modes. Snowshoers cannot ski or glide down any incline they happen to meet and snowshoes do not pack well and take a lot of space. The current ski industry only provides an approach ski that cannot move or climb as easily as snowshoes because the ski is longer in front of the footwear pivot point than behind it. In other words, when the ski is picked up with attached footwear to walk, the front portion of the ski pivots downward as the rear portion goes upward, potentially allowing the front ski tip to catch on the terrain. 
         [0006]    Additionally, current approach climbing ski systems offer cleats that penetrate the snow only when a user places the footwear heel closer to the ski, and when the footwear pivots upward the traction is pulled away from the snow. This system offers no traction when a user is walking with the heel of the user going upward, thus causing the traction system to be virtually worthless in the most aggressive climbing situation. Furthermore, the traction offers no propulsion from the forward pivot motion as it does in the operation of a snowshoe in which a toe cleat protrudes through the plane of the snowshoe. Traction for “side-hilling” may also be insufficient with a heel cleat alone. 
         [0007]    Another problem is that an approach ski has less surface area than a snowshoe, and thus is more prone to sink into soft snow. Conversely, approach skis are wider than downhill skis, and thus have poor edge control in sliding downhill. 
         [0008]    Because approach skis are typically used in conjunction with other skiing equipment such as a snowboard or downhill skis, minimizing the weight of the approach ski without compromising its strength is also an important factor needing improvement. 
         [0009]    An area in which the current state of the art is further deficient is the lack of modularity in footwear binding mechanisms between snowshoes, approach skis, and other types of skis. Thus the skier must carry additional footwear, adding to the overall weight of the total system. 
       SUMMARY OF THE INVENTION 
       [0010]    From the foregoing discussion, it should be apparent that a need exists for an apparatus, system, and method that combines the benefits and avoids the disadvantages of current snowshoe and approach ski technology. Beneficially, such an apparatus, system, and method would adapt to changing terrain with minimal reconfiguration while in use and would permit easy packing and storage while not in use. 
         [0011]    The present invention has been developed in response to the present state of the art, and in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available approach skis. Accordingly, the present invention has been developed to provide an apparatus, system, and method for approach skiing that overcomes many or all of the above-discussed shortcomings in the art. 
         [0012]    The apparatus to traverse the terrain is provided with a plurality of modules configured to functionally execute the necessary steps of deploying the approach skis, enabling and disabling a traction component as appropriate in response to the changing terrain, and compactly stowing and packing the approach skis while not in use. These modules in the described embodiments include a collapsing mechanism, traction component, and other related modules as described below. 
         [0013]    The apparatus, in one embodiment, is configured to include a traction component operative below the sliding surface on the underside of the ski while climbing uphill, but not substantially interfering with sliding downhill. 
         [0014]    The apparatus is further configured, in one embodiment, to be collapsible via a hinge or telescoping mechanism for easy packing and storage. 
         [0015]    In a further embodiment, the traction component may be configured to include a collapsing skin, having a stretchable portion adjacent to the hinge that allows the skin to easily collapse with the ski. The skin may be permanently or removably attached to the sliding surface on the underside of the ski, with fibers having a rearward orientation so as to resist sliding backward when climbing uphill but not substantially interfere with sliding forward downhill. Suitable fibers may include nylon or mohair. 
         [0016]    In a further embodiment, mechanisms are provided for locking the ski in a fully open deployed position and in a fully closed collapsed position. The mechanism for locking open may comprise a sliding member which also imparts additional strength and rigidity to the deployed ski. The mechanism for locking closed may comprise a loop that tightly encircles the tips of the collapsed ski. 
         [0017]    A footwear base may be provided to bind the user&#39;s footwear to the ski. A pivot joint positioned within the front half of the footwear base, hereinafter referred to as the toe end of the footwear base, allows the heel end to rotate up away from the ski with each step taken by the skier. The pivot joint may be comprised of an axle mounted transversely on the ski. 
         [0018]    In a further embodiment, the traction component may be configured to include a toe cleat extending over the sides of the ski, permanently or removably coupled to the toe end of the footwear base. When the footwear base pivots upward, the toe cleat rotates downward, gripping the terrain in a clawing fashion with each step taken by the skier. When the footwear base is level, the toe cleat is thereby elevated above the terrain so as not to substantially interfere with sliding downhill. 
         [0019]    For climbing steeper terrain, a heel riser may be optionally brought into position under the heel end of the footwear base. By maintaining the footwear base in a more level position while the ski is inclined uphill, the heel riser reduces the strain on the lower leg and Achilles tendon region of the skier. 
         [0020]    An advantage of the collapsing capability is that the approach ski may be made longer than otherwise possible and therefore less prone to sink into soft snow. In addition, by mounting the footwear base on the front half of the ski, the weight of the rear half of the ski will tend to raise the front tip of the ski up with each step taken by the skier, similar to the operation of a snowshoe. In another embodiment, a tensioning mechanism such as a bungee cord may be coupled between the front tip of the ski at one end and on or about the footwear base at the other end. 
         [0021]    In a further embodiment, a heel lock may be provided to hold the footwear level with the ski for improved stability and control in sliding downhill. In addition, because an approach ski is wider than a downhill ski, better leverage for edge control may be obtained by mounting the footwear base in higher position, on top of a supporting member on the upper surface of the ski. The supporting member may be a rail device which allows the position of the footwear base along the ski to be adjusted for optimal operation and/or to accommodate different sizes of footwear. 
         [0022]    The footwear base may also be configured to accept different types of footwear, including a soft-shelled boot or an AT boot. This capability may allow the approach ski to be interchangeable with other skiing equipment without changing footwear. Specially made footwear which integrates the pivoting and heel locking mechanisms of the footwear base directly into the sole of the footwear may also be provided, eliminating the need for a separate footwear base. With the toe cleat installed, the footwear base may also serve as a crampon device when removed from the approach ski. Removing the footwear base also facilitates the nested stacking of two or more skis for efficient transport. 
         [0023]    In a further embodiment, the traction component may be configured to include a removable fixed cleat. The removable fixed cleat may be temporarily attached to the ski for improved traction on steep uphill terrain and then removed when sliding downhill. 
         [0024]    A system of the present invention is also presented to augment and enhance the utility of the approach ski. The system may be embodied by the approach ski in conjunction with other skiing equipment, such as a snowboard or downhill skis. 
         [0025]    The system may further include porting equipment. The porting equipment may be a backpack capable of holding the approach skis inside it in a collapsed position, with straps on the outside to hold the other skiing equipment. 
         [0026]    A method of the present invention is also presented for approach skiing. The method in the disclosed embodiments substantially includes the steps necessary to carry out the functions presented above with respect to the operation of the described apparatus and system. In one embodiment, the method includes providing the collapsing ski, deploying the ski into a locked open position, traversing the terrain, collapsing the ski into a locked closed position, and stowing the ski. The method also may include enabling a traction component when climbing uphill and disabling the traction component when sliding or gliding as desired. 
         [0027]    In a further embodiment, the method includes utilizing other skiing equipment such as a snowboard or downhill skis when a destination skiing site has been reached via the approach skis. 
         [0028]    Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment. 
         [0029]    Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. 
         [0030]    These features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which: 
           [0032]      FIG. 1  is a side view of a collapsing approach ski. 
           [0033]      FIG. 2  is a bottom perspective view of a collapsing approach ski. 
           [0034]      FIG. 3  is a detailed view of a collapsing member. 
           [0035]      FIG. 4  is a detailed view of a collapsing skin for a collapsing approach ski. 
           [0036]      FIG. 5  is a detailed view of a collapsing skin in a collapsed position. 
           [0037]      FIG. 6  is a top plan view of a collapsing approach ski. 
           [0038]      FIG. 7  is a detailed view of a sliding member. 
           [0039]      FIG. 8  is a top plan view of a collapsing approach ski in a collapsed position. 
           [0040]      FIG. 9  is a side view of a collapsing approach ski in a collapsed position. 
           [0041]      FIG. 10  is a side view of a collapsing approach ski with a pivoting toe cleat. 
           [0042]      FIG. 11  is a detailed side view of a pivoting toe cleat. 
           [0043]      FIG. 12  is a detailed perspective view of a pivoting toe cleat. 
           [0044]      FIG. 13  is a bottom perspective view of a collapsing approach ski with a cleat traction component installed. 
           [0045]      FIG. 14  is a bottom perspective view of a collapsing approach ski with a collapsing skin installed as an additional traction component. 
           [0046]      FIG. 15  is a flow chart illustrating a method for using the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0047]    Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. 
         [0048]    Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. 
         [0049]    The schematic flow chart diagrams included herein are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented method. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types may be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. 
         [0050]      FIG. 1  is a side view of a collapsing approach ski  100 . A front ski segment  102  is connected to a rear ski segment  104  via a hinge  106 . Hinge pins  108  allow front ski segment  102  and rear ski segment  104  to rotate relative to hinge  106 . One embodiment is an easily manufactured light weight ski  100  that can be made in composite plastics and elastomers. In an embodiment the ski  100  is less than 6 inches wide. Additionally ¼ inch steel reinforcement rods can be used as support in the construction, making plastic skis strong but light and durable. Another embodiment allows the ski  100  to be constructed in metal, or plastic, or carbon fiber, or typical layered wood or composite construction with an optional metal edge. 
         [0051]    A rail device  110  on front ski segment  102  holds a footwear base  112  via corresponding holes  114  into which one or more axles  116  are inserted. The right rail having a plurality of holes  114  is visible in this view. There is an identical left rail with corresponding holes  114  on the left side of front ski segment  102 . With one axle  116  through corresponding holes  114  in rail device  110  and a toe end of footwear base  112 , footwear base  112  is free to pivot allowing the heel of the skier to rotate up away from the upper surface of ski  100  with each step taken. A plurality of holes  114  in rail device  110  permits the footwear base  112  to be moved forward or backward on the ski  100 , allowing a variety of footwear sizes to be accommodated as well as pivoting differently on the ski  100 . In another embodiment, the pivoting capability of the footwear base  112  may be incorporated directly into the footwear itself, eliminating the need for a separate footwear base. 
         [0052]    The rail device  110  may be constructed integrally with the ski  100  or as a separate piece to be mounted on any make and model of ski or snowshoe so that they may also have pivotally equipped footwear and bindings. The rail device  110  generally sits laterally on the periphery of the ski  100  but could be constructed anywhere on the ski  100  admitting of a footwear pivoting mechanism. The rail device may be constructed in metals, composites, carbon fiber, wood, and plastics. 
         [0053]    If the ski is more than 6 inches wide at its widest point the sole of the user&#39;s footwear must be at least ½ inch or more mounted above the bottom side of the ski device to allow some edge control. Normally when a ski design is wide its binding placement should be raised considerably. One embodiment of the present invention is having a separate rail system that may be mounted to a multitude of ski designs of different makes and models. 
         [0054]    In an embodiment, the toe end of footwear base  112  should be positioned with approximately two thirds of the length of the ski  100  behind it, like a typical snowshoe, thus causing the front tip of the ski  100  to move upward when the user raises his foot up to take a step. 
         [0055]    “Locked heel style” skiing may be achieved by simply inserting an axle  116  through the heel end of footwear base  112  and the corresponding holes  114  in rail device  110 . Thus footwear base  112  has at least two holes  114  that accept axles  116 . When two or more axles  116  are in place, including the axle  116  in the toe end, footwear base  112  cannot pivot thus providing a locked heel position. Each axle  116  may be locked in place by a mechanism that prevents it from moving out of position in the rail device  110 , such as a cotter pin. This style may also be used on a snowshoe ski system. 
         [0056]    The ski  100  may be held in a fully open deployed position with a sliding lock  118  which is kept in place by a cotter pin  120 . The ski  100  may be held in a fully closed collapsed position by encircling the tip of front ski segment  102  with a locking loop  122  attached to the tip of rear ski segment  104 . 
         [0057]    A spring loaded like suspension may also be used to pull the front ski tip in an upward motion in the form of a tensioning member  124  that can be configured in a variety of ways. One such way is coupling one end of a “bungee cord” type device to the front end of the ski and another end to the footwear, binding, binding strap, lower leg, or footwear base  112 . This tensioning member  124  may also be used on a snowshoe. 
         [0058]    Also disclosed is a heel riser comprised of a heel block  126  which retains a heel lift  128  that relieves strain on the lower part of the leg and Achilles region. The heel lift  128  may be raised and lowered dependent upon its desired use. A further embodiment is a heel lift  128  able to be set right into the top construction of the ski  100 . Additionally means may exist for a separate heel lift  128  and may be bolted to the top side of the ski  100 . The top side of the ski  100  may include attachment means like the use of pems (not shown) to couple the heel block  126 . 
         [0059]      FIG. 2  is a bottom perspective view of a collapsing approach ski  100 . The sliding surface  202  on the underside of the ski  100  is visible in this view. In one embodiment a piece of permanently attached skin  204  is shown on front ski segment  102 . The tip of an axle  116  is visible protruding from the front hole  114  of rail device  110 , thereby allowing footwear base  112  to freely pivot. Axle  116  may be either permanent or removable. 
         [0060]      FIG. 3  is a detailed view of a collapsing member. Two ¼ inch steel hinge pins  108  are mounted to hinge  106  and to respective front ski segment  102  and rear ski segment  104  pivot hinges (not shown). The hinge pins  108  are held in place by E-clips (not shown). 
         [0061]      FIG. 4  is a detailed view of a collapsing skin  400  for a collapsing approach ski  100 . Collapsing skin  400  is configured to flex in its center when collapsed with the ski, comprising a front skin segment  402  and rear skin segment  404  connected via stretchable portion  406  at sewn locations  408 . In one embodiment, the collapsing skin  400  may be attached to a tip of ski  100  via an attachment loop  410 . 
         [0062]      FIG. 5  is a detailed view of a collapsing skin  400  in a collapsed position. Collapsing skin  400  has stretchable portion  406  that flexes adjacent to hinge  108  when the ski  100  is placed into a fully closed collapsed position. 
         [0063]      FIG. 6  is a top plan view of a collapsing approach ski  100 . The ski  100  is held in a fully open deployed position by sliding lock  118  locking the front ski segment  102 , rear ski segment  104  and hinge  106  using guiders  602 . Guiders  602  are present on top surface of the ski  100  and hinge  106 . When the sliding lock  118  is engaged in all of the guiders  602  the ski  100  will remain in the ski mode. 
         [0064]      FIG. 7  is a detailed view of a sliding member. Sliding lock  118  is constructed of a ¼ inch stainless steel u-shaped rod that may be moved to a forward position bridging collapsing hinge  108  and locked into position by cotter pin  120  inserted into slider hole  702 , or a drop-nose pin or T-lock with a spring bias system (not shown). The sliding lock  118  also acts as a brace for the ski  100  offering much support and strength. The sliding lock  118  has a handle  704  with which the user can easily move the sliding lock  118  back and forth. 
         [0065]      FIG. 8  is a top plan view of a collapsing approach ski  100  in a fully closed collapsed position. Hinge  106  allows the ski  100  to be collapsed as shown, shortening the length of the ski  100  into a compact size for convenient storage on a snowmobile, pack, or transport for the military. 
         [0066]      FIG. 9  is a side view of the collapsing approach ski  100  in the fully closed collapsed position. When the sliding lock  118  is moved toward the back end of the ski  100  past hinge  108  the rear ski segment  104  may by rotated to fit so that the bottom of rear ski segment  104  and front ski segment  102  are touching. The locking loop  122  holds the tips of ski  100  together in the fully closed collapsed position for easy storage. 
         [0067]      FIG. 10  is a side view of a collapsing approach ski  100  with a pivoting toe cleat  1002  under the ball of the foot up to or past the toe region, illustrating the ski  100  with the footwear base  112  pivoting upward and the toe cleat  1002  protruding downward below the sliding surface  202  to penetrate the snow or ice. Thus the ski  100  may climb with a traction component oriented somewhat like a snowshoe cleat. The toe cleat  1002  may surround the outer periphery of the lateral sides of the ski  100  or the toe cleat  1002  may even be equipped to penetrate an opening through the ski  100  itself, thereby engaging the terrain. 
         [0068]    The toe cleat  1002  may be permanently or removably coupled to the footwear base  112  by inserting axle  116  through hole  1004  in tab  1006 . The footwear base  112  may also be mounted to rail device  110  using the same axle  116 . 
         [0069]    Also shown are the heel lift  128  and the heel block  126 . These devices relieve the lower leg and Achilles tendon region during climbing. The footwear base may include heel strap  1008  and toe strap  1010  connected to strap holes  1012  for soft shelled boots or may be configured to accept AT boots. Additionally, pivotal footwear for devices meant for sliding over snow may be accepted by the ski device without the need for a separate footwear base  112 . Another embodiment of the present invention is the ability of the ski  100  to accept a separate snowshoe binding manufactured for the purpose of being able to be used on both a snowshoe and a ski  100 . Thus, the user can economically purchase separate items of one device to use on another when it comes to skiing, snowshoeing, and any other winter sport with which the parts may be compatible. The footwear base  112  may hold a variety of footwear, including hiking boots, ski boots, snowboard boots, cross-country ski boots, or a slip-over type device wherein the user places a foot. The slip-over device may be permanently or removably coupled to the footwear base. The slip-over device may also have multiple pivots to be used on a variety of products including a snowshoe, ski, snowboard, cross-country ski and split-board. 
         [0070]      FIG. 11  is a detailed side view of a pivoting toe cleat  1002  having a hole  1004  through a tab  1006 . 
         [0071]      FIG. 12  is a detailed perspective view of a pivoting toe cleat  1002 . The axle  116  is inserted from left to right through holes  1004  in tabs  1006 . Axle  116  is retained in position by an E-clip  1202  on the left and locked into place on the right by either a cotter pin  1204  or a T-lever (not shown). 
         [0072]      FIG. 13  is a bottom perspective view of a collapsing approach ski  100  with a cleat traction component installed, including a removable fixed (stationary) cleat  1302  mounted to rear ski segment  104 . One embodiment includes a spring loaded quick-release fixed cleat  1302  that may extend below the sliding surface  202  of the ski  100  with the spring system locking to the top or bottom side of ski  100 . Additionally “side hilling” may also be aided by toe cleat  1002  and fixed cleat  1302 . Toe cleat  1002  and fixed cleat  1302  may be used together or separately, and toe cleat  1002  may be fixed or pivoting. 
         [0073]    Also shown are the hinge  106  and the hinge pins  108  in accordance with the present invention. The footwear base  112  can be seen as well as strap holes  1012  in which straps may be mounted to hold a soft shelled boot. 
         [0074]      FIG. 14  is a bottom perspective view of a collapsing approach ski  100  with a collapsing skin  400  installed as an additional traction component. The collapsing skin  400  may be configured to have attachment loops  410  to the ski  100 , operating in conjunction with fixed cleat  1302  and pivoting toe cleat  1002  that reach far below the sliding surface  202  for optimum climbing power. The fixed cleat  1302  and the pivoting toe cleat  1002  may be aligned so that when the ski  100  is collapsed they may overlap the periphery of the ski  100  in the fully closed collapsed position (not shown). 
         [0075]    The footwear base  112  can be removed from the ski  100  by removing axle  116 , permitting footwear base  112  to be used as a separate climbing device such as a crampon, or simply to make the ski  100  easier to stow. Another embodiment is a quick-release allowing the axle  116  to release from the ski  100  thus allowing the footwear base  112  to be removed. When the footwear base  112  is removed the ski  100  can be stowed conveniently in a pack. Yet another embodiment of the present invention is the optional means of locking unoccupied skis  100  to each other in a fully locked manner so that the lock manually needs to be disengaged to release one ski  100  from another. Also included in this embodiment is the ability for more than two skis  100  to hook to each other up to a large amount for easy transport, especially in military operations. 
         [0076]      FIG. 15  is a flow chart illustrating a method for using the present invention. The method  1500  starts  1502  and a collapsing approach ski  100  is provided  1504 . The skier deploys  1506  the ski  100  and locks  1508  it in the fully open deployed position. If the terrain is downhill  1510  then the skier detaches  1512  the fixed cleat  1302 , lowers  1514  the heel lift  128 , and locks  1516  the footwear base  112  into the locked heel position, thereby enabling the skier to slide  1518  downhill with good control and without substantial interference. Note that the toe cleat  1002  need not be removed since it may pivot up out of the way in the locked heel position. Note also that the collapsing skin  400  need not be removed, since its fibers have a rearward orientation so as not to substantially interfere with sliding  1518  forward. If the terrain is not downhill  1510  then the skier unlocks  1520  the footwear base  112  so that it may freely rotate upward with each step taken by the skier while simultaneously engaging the pivoting toe cleat  1002  into the terrain for improved traction. If the uphill terrain is steep  1522 , then the skier also attaches  1524  a fixed cleat  1302  for additional traction and raises  1526  heel lift  128  so as relieve strain on the lower leg and Achilles region. The skier is thus enabled to walk  1528  with a traction component appropriate to the terrain. As the skier reaches various points along the terrain, the skier may decide to continue  1530 , repeating the foregoing steps starting with the step of determining whether the terrain is downhill  1510  or not. If the skier decides not to continue, then the skier collapses  1532  the ski  100 . Note that the collapsing skin  400  need not be removed, since the stretchable portion  406  permits it to be collapsed  1532  along with the ski  100 . The skier then locks  1534  the ski  100  into the fully closed collapsed position, stows  1536  the ski  100 , and the method  1500  ends  1538 . 
         [0077]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.