Patent Publication Number: US-2018050785-A1

Title: Airship including aerodynamic, floatation, and deployable structures

Description:
PRIORITY 
     This application claims the benefit of priority of U.S. Provisional Application No. 61/470,025, filed Mar. 31, 2011, entitled “AIRSHIP INCLUDING AERODYNAMIC, FLOATATION, AND DEPLOYABLE STRUCTURES,” the entire content of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure is directed to an airship and features therefor. 
     BACKGROUND 
     The present invention relates to an airship including aerodynamic, floatation, and deployable structures. Each of U.S. Pat. No. 7,866,601, issued Jan. 11, 2011, U.S. patent application Ser. No. 12/957,989, filed Dec. 1, 2010, U.S. patent application Ser. No. 12/222,355, filed Aug. 7, 2008, U.S. Pat. No. D583,294, issued Dec. 23, 2008, U.S. Design patent application No. 29/366,163, filed Jul. 20, 2010, and U.S. Provisional Patent Application No. 61/366,125, filed Jul. 20, 2010 discloses subject matter related to the present invention and the contents of these applications are incorporated herein by reference in their entirety. 
     Aerostatic lighter-than-air airships have seen substantial use since 1783 following the first successful manned flight of the Montgolfier brothers&#39; hot air balloon. Numerous improvements have been made since that time, but the design and concept of manned hot air balloons remains substantially similar. Such designs may include a gondola for carrying a pilot and passengers, a heating device (e.g., a propane torch), and a large envelope or bag affixed to the gondola and configured to be filled with air. The pilot may then utilize the heating device to heat the air until the buoyant forces of the heated air exert sufficient force on the envelope to lift the balloon and an attached gondola. Navigation of such an airship has proven to be difficult, mainly due to wind currents and lack of propulsion units for directing the balloon. 
     To improve on the concept of lighter-than-air flight, some lighter-than-air airships have evolved to include propulsion units, navigational instruments, and flight controls. Such additions may enable a pilot of such an airship to direct the thrust of the propulsion units in such a direction as to cause the airship to proceed as desired. Airships utilizing propulsion units and navigational instruments typically do not use hot air as a lifting gas (although hot air may be used), with many pilots instead preferring lighter-than-air lifting gases such as hydrogen and helium. These airships may also include an envelope for retaining the lighter-than-air gas, a crew area, and a cargo area, among other things. The airships are typically streamlined in a blimp- or zeppelin-like shape, which, while providing reduced drag, may subject the airship to adverse aeronautic effects (e.g., weather cocking, a.k.a. wind cocking). 
     Airships other than traditional hot air balloons may be divided into several classes of construction: rigid, semi-rigid, non-rigid, and hybrid type. Rigid airships typically possess rigid frames containing multiple, non-pressurized gas cells or balloons to provide lift. Such airships generally do not depend on internal pressure of the gas cells to maintain their shape. Semi-rigid airships generally utilize some pressure within a gas envelope to maintain their shape, but may also have frames along a lower portion of the envelope for purposes of distributing suspension loads into the envelope and for allowing lower envelope pressures, among other things. Non-rigid airships typically utilize a pressure level in excess of the surrounding air pressure in order to retain their shape and any load associated with cargo carrying devices is supported by the gas envelope and associated fabric. The commonly used blimp is an example of a non-rigid airship. 
     Hybrid airships may incorporate elements from other airship types, such as a frame for supporting loads and an envelope utilizing pressure associated with a lifting gas to maintain its shape. Hybrid airships also may combine characteristics of heavier-than-air airship (e.g., airplanes and helicopters) and lighter-than-air technology to generate additional lift and stability. It should be noted that many airships, when fully loaded with cargo and fuel, may be heavier than air and thus may use their propulsion system and shape to generate aerodynamic lift necessary to stay aloft. However, in the case of a hybrid airship, the weight of the airship and cargo may be substantially compensated for by lift generated by forces associated with a lifting gas such as, for example, helium. These forces may be exerted on the envelope, while supplementary lift may result from aerodynamic lift forces associated with the hull. 
     A lift force (i.e., buoyancy) associated with a lighter-than-air gas may depend on numerous factors, including ambient pressure and temperature, among other things. For example, at sea level, approximately one cubic meter of helium may balance approximately a mass of one kilogram. Therefore, an airship may include a correspondingly large envelope with which to maintain sufficient lifting gas to lift the mass of the airship. Airships configured for lifting heavy cargo may utilize an envelope sized as desired for the load to be lifted. 
     Hull design and streamlining of airships may provide additional lift once the airship is underway, however, previously designed streamlined airships, in particular, may experience adverse effects based on aerodynamic forces because of such hull designs. For example, one such force may be weather cocking, which may be caused by ambient winds acting on various surfaces of the airship. The term “weather cocking” is derived from the action of a weather vane, which pivots about a vertical axis and always aligns itself with wind direction. Weather cocking may be an undesirable effect that may cause airships to experience significant heading changes based on a velocity associated with the wind. Such an effect may thereby result in lower ground speeds and additional energy consumption for travel. Lighter-than-air airships may be particularly susceptible to weather cocking and, therefore, it may be desirable to design a lighter-than-air airship to minimize the effect of such forces. 
     On the other hand, airships having a hull shape with a length that is similar to the width may exhibit reduced stability, particularly at faster speeds. Accordingly, the aspect ratio of length to width (length:width) of an airship may be selected according to the intended use of the airship. 
     Landing and securing a lighter-than-air airship may also present unique problems based on susceptibility to adverse aerodynamic forces. Although many lighter-than-air airships may perform “vertical take off and landing” (VTOL) maneuvers, once such an airship reaches a point near the ground, a final landing phase may entail ready access to a ground crew (e.g., several people) and/or a docking apparatus for tying or otherwise securing the airship to the ground. Without access to such elements, the airship may be carried away by wind currents or other uncontrollable forces while a pilot of the airship attempts to exit and handle the final landing phase. Therefore, systems and methods enabling landing and securing of an airship by one or more pilots may be desirable. 
     In addition, airships may include passenger and/or cargo compartments, typically suspended below the hull of the airship. However, such placement of a passenger/cargo compartment can have an adverse affect on aerodynamics and, consequently, performance capabilities of the airship. For example, an externally-mounted compartment increases drag in both fore-aft and port-starboard directions, thus requiring more power to propel the airship, and rendering the airship more sensitive to cross-winds. Further, because an externally-mounted compartment is typically on the bottom of the airship, the compartment is offset from the vertical center of the airship and, therefore, may lead to instability as the added drag due to the compartment comes in the form of forces applied substantially tangential to the outer hull of the airship, causing moments that tend to twist and/or turn the airship undesirably. Such adverse moments require stabilizing measures to be taken, typically in the form of propulsion devices and/or stabilizing members (e.g., wings). However, propulsion devices require power, and stabilizing members, while providing stability in one direction, may cause instability in another direction. For example, a vertically oriented stabilizer can provide lateral stability but may causes increased fore-aft drag, and may also render the airship more susceptible to cross winds. It would be advantageous to have an airship with a configuration that can carry passengers/cargo but does not cause the adverse affects typically associated with externally-mounted compartments and/or stabilizers mentioned above. 
     In addition, it may be desirable to be able to land an airship on water. However, externally mounted pontoons may exhibit excess drag, possibly causing instability. Accordingly it would be advantageous to have an airship with floatation structures that do not cause such excess drag. 
     Further, it may be desirable to be able to deploy various types of industrial apparatus from an airship. However, as noted above, any externally mounted apparatus may cause excess drag, and thus, instability. Therefore, it would be advantageous to have an airship with deployable apparatuses that do not cause excess drag as such. 
     The present disclosure is directed to addressing one or more of the desires discussed above utilizing various exemplary embodiments of an airship. 
     SUMMARY 
     In one exemplary aspect, the present disclosure is directed to an airship. The airship includes a hull configured to contain a gas, at least one propulsion assembly coupled to the hull and including a propulsion device, and at least one aerodynamic component including a plurality of fairing structures including one or more slats, wherein the at least one aerodynamic component is associated with the hull and is configured to direct airflow around the airship. 
     In another exemplary aspect, the present disclosure is directed to an airship. The airship includes a hull configured to contain a gas, at least one propulsion assembly coupled to the hull and including a propulsion device, and at least one floatation structure configured to support the airship during a water landing. 
     In a further exemplary aspect, the present disclosure is directed to an airship. The airship includes a hull configured to contain a gas, at least one propulsion assembly coupled to the hull and including a propulsion device, and at least one deployable apparatus housed within the hull and deployable from the hull for operation unrelated to the flight control or landing of the airship. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an airship including aerodynamic components according to an exemplary disclosed embodiment; 
         FIG. 2  illustrates an exemplary support structure of the disclosed airship; 
         FIG. 3  illustrates an exemplary disclosed hull material of the disclosed airship; 
         FIG. 4  illustrates an exemplary embodiment of the disclosed airship having a substantially oblate spheroid shape, wherein the aspect ratio between the hull length to the hull width is 1 to 1 (1:1); 
         FIG. 5  illustrates an exemplary embodiment of the disclosed airship having a substantially oblate spheroid shape, wherein the aspect ratio between the hull length to the hull width is 4:3; 
         FIG. 6  illustrates an exemplary embodiment of the disclosed airship having a substantially oblate spheroid shape, wherein the aspect ratio between the hull length to the hull width is 3:2; 
         FIG. 7  illustrates an exemplary embodiment of the disclosed airship having a substantially oblate spheroid shape, wherein the aspect ratio between the hull length to the hull width is 2:1; 
         FIG. 8  illustrates an exemplary cockpit support structure and front landing gear assembly; 
         FIG. 9  illustrates an exemplary propulsion assembly and mounting assembly; 
         FIG. 10  illustrates a bottom view of the disclosed airship, showing an exemplary array of propulsion assemblies; 
         FIG. 11  illustrates a bottom view of the disclosed airship, showing another exemplary array of propulsion assemblies; 
         FIG. 12A  illustrates an exemplary power supply system; 
         FIG. 12B  illustrates an exemplary disclosed airship embodiment having an exemplary embodiment of a solar energy converting device; 
         FIG. 13A  illustrates a cutaway view of an exemplary disclosed airship embodiment having cargo compartments, wherein a transport system is deployed from the cargo compartments; 
         FIG. 13B  illustrates a cutaway view of another airship embodiment wherein the cargo compartments, themselves, are deployed; 
         FIG. 14  illustrates a cutaway view of an exemplary airship embodiment showing a plurality of internal bladders; 
         FIGS. 15A-15D  illustrate exemplary features of an empennage assembly; 
         FIG. 16  illustrates a partial cross-sectional view of an exemplary airship embodiment having front landing gear deployable with a passenger compartment; 
         FIG. 17  illustrates an exemplary embodiment of an airship having bottom-mounted aerodynamic components; 
         FIG. 18  is a rear view of an airship having an aerodynamic component spanning the entire width of the top portion of the airship; 
         FIG. 19  is an exemplary embodiment of an airship having aerodynamic structures that do not protrude from the envelope of the hull of the airship; 
         FIG. 20  is an exemplary airship embodiment having overlapping aerodynamic components; 
         FIG. 21  is an exemplary airship embodiment wherein fairing structures of the aerodynamic component are diagonally oriented; 
         FIG. 22  is a cross-sectional view of an exemplary airship embodiment having aerodynamic components configured to produce aerodynamic lift during flight; 
         FIG. 23  is a cutaway view of another exemplary embodiment of an airship having multiple aerodynamic components; 
         FIG. 24  is a rear view of another exemplary embodiment of an airship having multiple aerodynamic components; 
         FIG. 25  is an exemplary airship embodiment having floatation structures; 
         FIG. 26  is another exemplary airship embodiment having floatation structures; 
         FIGS. 27 and 28  are exemplary airship embodiments having deployable floatation structures; 
         FIG. 29  is an exemplary airship embodiment having a deployable apparatus; and 
         FIG. 30  is a block diagram of an exemplary embodiment of a computer configured to control various aspects of the disclosed airship. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to the drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
     The accompanying figures depict exemplary embodiments of an airship  10 . Airship  10  may be configured for VTOL as well as navigation in three dimensions (e.g., X, Y, and Z planes). As shown in  FIG. 1 , for example, airship  10  may include a hull  12  configured to contain a gas. Airship  10  may also include an empennage assembly  25  coupled to airship  10 , at least one propulsion assembly  31  coupled to airship  10 , a power supply system  1000  for delivering power to propulsion assembly  31  (see  FIG. 12A ), and a cargo system  1100  for carrying passengers and/or freight (see, e.g.,  FIGS. 13A and 13B ). Alternatively, or additionally, in some embodiments airship  10  may include one or more aerodynamic components  2000  (see, e.g.,  FIG. 1 ), and one or more floatation structures  4000  (see, e.g.,  FIG. 25 ). Further, in some embodiments, airship  10  may include a deployable apparatus  5000  (see, e.g.,  FIG. 29 ). 
     Throughout this discussion of various embodiments, the terms “front” and/or “fore” will be used to refer to areas within a section of airship  10  closest to forward travel, and the term “rear” and/or “aft” will be used to refer to areas within a section of airship  10  closest to the opposite direction of travel. Moreover, the term “tail” will be used to refer to a rear-most point associated with hull  12 , while the term “nose” will be used to refer to the forward-most point within the front section of hull  12 . 
     The accompanying figures illustrate various axes relative to the exemplary airship  10  for reference purposes. For example, as shown in  FIG. 1 , airship  10  may include a roll axis  5 , a pitch axis  6 , and a yaw axis  7 . Roll axis  5  of airship  10  may correspond with an imaginary line running through hull  12  in a direction from, for example, the tail to the nose of airship  10 . Yaw axis  7  of airship  10  may be a central, vertical axis corresponding with an imaginary line running perpendicular to roll axis  5  through hull  12  in a direction from, for example, a bottom surface of hull  12  to a top surface of hull  12 . Pitch axis  6  may correspond to an imaginary line running perpendicular to both yaw and roll axes, such that pitch axis  6  runs through hull  12  from one side of airship  10  to the other side of airship  10 , as shown in  FIG. 1 . “Roll axis” and “X axis” or “longitudinal axis”; “pitch axis” and “Y axis;” and “yaw axis” and “Z axis” may be used interchangeably throughout this discussion to refer to the various axes associated with airship  10 . One of ordinary skill in the art will recognize that the terms described in this paragraph are exemplary only and not intended to be limiting. 
     Hull 
     Hull  12  may include a support structure  20  (see  FIG. 2 ), and one or more layers of material  14  substantially covering support structure  20  (see  FIG. 3 ). In some embodiments, airship  10  may be a “rigid” airship. As used herein, the term “rigid airship” shall refer to an airship having a rigid framework, and containing one or more non-pressurized gas cells or bladders to provide lift, wherein the hull of the airship does not depend on internal pressure of the gas cells to maintain its shape. 
       FIG. 2  illustrates an exemplary support structure  20  according to some embodiments of the present disclosure. For example, support structure  20  may be configured to define a shape associated with airship  10 , while providing support to numerous systems associated with airship  10 . Such systems may include, for example, hull  12 , propulsion assemblies  31 , power supply system  1000 , and/or cargo system  1100 . As shown in  FIG. 2 , support structure  20  may be defined by one or more frame members  22  interconnected to form a desired shape. For example, airship  10  may include a substantially circular, oval, elliptical, or otherwise oblong, peripheral beam (e.g., a keel hoop  120 ). Keel hoop  120  may include one or more frame sections with a defined radius of curvature that may be affixed to one another to form keel hoop  120  of a desired radius or oblong shape and size. In some embodiments, keel hoop  120  may have a diameter of, for example, approximately 21 meters. In oblong embodiments, keel hoop  120  may be similarly sized. Support structure  20  may also include a longitudinal frame member  124  configured to extend in a longitudinal direction from a fore portion of keel hoop  120  to a rear portion of keel hoop  120 . 
     To maximize a lifting capacity associated with airship  10 , it may be desirable to design and fabricate support structure  20  such that weight associated with support structure  20  is minimized while strength, and therefore resistance to aerodynamic forces, for example, is maximized. In other words, maximizing a strength-to-weight ratio associated with support structure  20  may provide a more desirable configuration for airship  10 . For example, one or more of frame members  22  may be constructed from light weight, but high strength, materials including, for example, a substantially carbon-based material (e.g., carbon fiber) and/or aluminum, among other things. 
     Hull  12  may be configured to retain a volume of lighter-than-air gas. In some embodiments, hull  12  may include at least one envelope  282  sewn or otherwise assembled of fabric or material configured to retain a lighter-than-air gas, as shown in  FIG. 3 . Envelope  282  may be fabricated from materials including, for example, aluminized plastic, polyurethane, polyester, laminated latex, mylar, and/or any other material suitable for retaining a lighter-than-air gas. 
     Lighter-than-air lifting gasses for use within envelope  282  of hull  12  may include, for example, helium, hydrogen, methane, and ammonia, among others. The lift force potential of a lighter-than-air gas may depend on the density of the gas relative to the density of the surrounding air or other fluid (e.g., water). For example, the density of helium at 0 degrees Celsius and 101.325 kilo-Pascals may be approximately 0.1786 grams/liter, while the density of air at 0 degrees C. and 101.325 kilo-Pascals may be approximately 1.29 g/L. Neglecting the weight of a retaining envelope, equation (1) below illustrates a simplified formula for calculating a buoyant force, Fbuoyant, based on volume of a lighter-than-air gas, where Df is a density associated with an ambient fluid, Dlta is a density associated with the lighter-than-air gas, gc is the gravity constant, and V is the volume of the lighter-than-air gas. 
         F buoyant=( Df −Dlta)*gc* V   (1)
 
     Simplifying the equation based on a volume of helium suspended within air at 0 degrees C. and 101.325 kilo-Pascals, a buoyant force may be determined to be approximately Fbouyant/gc=1.11 grams per liter (i.e., approximately 1 kg per cubic meter of helium). Therefore, based on the lighter-than-air gas chosen, an internal volume of first envelope  282  associated with hull  12  may be selected such that a desired amount of lift force is generated by a volume of lighter-than-air gas. Equation (2) below may be utilized to calculate such a desired volume for aerostatic lift, taking into account the mass, M, of airship  10 . 
         V&gt;M /( Df −Dlta)  (2)
 
     In addition, in some embodiments, hull  12  may be formed of a self-sealing material. One or more layers of hull  12  may be selected from known self-sealing materials, e.g., a viscous substance. 
     Hull  12  of airship  10  may have a three-dimensional shape that is selected according to intended functionality and use of the airship. Factors that may be considered in selecting an airship shape may include the size, weight, and/or placement of the intended payload, speed of travel, range, longevity, maneuverability, etc. According to these and other factors, a number of design variables, many having an influence on hull shape, may be considered and balanced in arriving at a hull shape. Such variables may include, for example, volume/capacity of lighter than air gas, drag coefficient (including frontal, side, and vertical drag), weight, stability, etc. 
     In some embodiments, hull  12  of airship  10  may be “lenticular” in shape, i.e., substantially an oblate spheroid having a length, a width, and a height, wherein the length and the width have approximately the same dimension. (See  FIG. 4 .) For example, the dimensions of an oblate spheroid shape may be approximately described by the representation A=B&gt;C, where A is a length dimension (e.g., along roll axis  5 ); B is a width dimension (e.g., along pitch axis  6 ); and C is a height dimension (e.g., along yaw axis  7 ) of an object. In other words, an oblate spheroid may have an apparently circular planform with a height (e.g., a polar diameter) less than the diameter of the circular planform (e.g., an equatorial diameter). For example, according to some embodiments, hull  12  may include dimensions as follows: A=21 meters; B=21 meters; and C=7 meters. 
     In other embodiments, hull  12  of airship  10  may be substantially oblong. That is, hull  12  may have a length, a width, and a height, wherein an aspect ratio between the length and the width is greater than 1 to 1 ( 1 : 1 ). For example, in some embodiments the aspect ratio of hull length to hull width may be between approximately 4:3 and 2:1. Particularly, in some embodiments, the aspect ratio may be approximately 4:3, as shown in  FIG. 5 . In other embodiments, the aspect ratio may be approximately 3:2, as shown in  FIG. 6 . In still other embodiments, the aspect ratio may be approximately 2:1, as shown in  FIG. 7 . 
     In addition to aerostatic lift generated by retention of a lighter-than-air gas, hull  12  may be configured to generate at least some aerodynamic lift when placed in an airflow (e.g., airship  10  in motion and/or wind moving around hull  12 ) based on the aerodynamic shape of hull  12  and/or on an associated angle of attack and airflow velocity relative to airship  10 . 
     As shown in  FIG. 8 , support structure  20  may include one or more frame members comprising a chassis  705 . In some embodiments, chassis  705  may be part of cargo system  1100 , e.g., as part of a cockpit. In other embodiments, chassis  705  may be integrated with hull  12  independent of cargo system  1100 . Chassis  705  may include high strength-to-weight ratio materials including, for example, aluminum and/or carbon fiber. In some embodiments, the one or more frame members of chassis  705  may be constructed as substantially tubular and may include a carbon fiber/resin composite and honeycomb-carbon sandwich. The honeycomb-carbon sandwich may include a carbon mousse or foam-type material. In such embodiments, individual frame members may be fabricated in an appropriate size and shape for assembly of chassis  705 . Such construction may lead to a suitable strength-to-weight ratio for chassis  705  as desired for a particular purpose of airship  10 . One of skill in the art will recognize that chassis  705  may be constructed in numerous configurations without departing from the scope of the present disclosure. The configuration of chassis  705  shown in  FIG. 8  is merely exemplary. 
     Propulsion Assemblies 
       FIG. 9  illustrates an exemplary embodiment of propulsion assemblies  31 . For example, as shown in  FIG. 9 , propulsion assemblies  31  may include a power source  410 , a propulsion device (such as power conversion unit  415 ), and a propulsion unit mount  430 . Power source  410  may be operatively coupled to and configured to drive power conversion unit  415 . Power source  410  may include, for example, electric motors, liquid fuel motors, gas turbine engines, and/or any suitable power source configured to generate rotational power. Power source  410  may further include variable-speed and/or reversible type motors that may be run in either direction (e.g., rotated clockwise or counterclockwise) and/or at varying rotational speeds based on control signals (e.g., signals from computer  600  (e.g., as shown in  FIG. 30 )). Power source  410  may be powered by batteries, solar energy, gasoline, diesel fuel, natural gas, methane, and/or any other suitable fuel source. 
     As shown in  FIG. 9 , each propulsion assembly  31  may include a power conversion unit  415  configured to convert the rotational energy of power source  410  into a thrust force suitable for acting on airship  10 . For example, power conversion unit  415  may include a propulsion device, such as an airfoil or other device that, when rotated, may generate an airflow or thrust. For example, power conversion unit  415  may be arranged as an axial fan (e.g., a propeller, as shown in  FIG. 9 ), a centrifugal fan, and/or a tangential fan. Such exemplary fan arrangements may be suited to transforming rotational energy produced by power source  410  into a thrust force useful for manipulating airship  10 . One of ordinary skill in the art will recognize that numerous configurations may be utilized without departing from the scope of the present disclosure. 
     Power conversion unit  415  may be adjustable such that an angle of attack of power conversion unit  415  may be modified. This may allow for modification to thrust intensity and direction based on the angle of attack associated with power conversion unit  415 . For example, where power conversion unit  415  is configured as an adjustable airfoil (e.g., variable-pitch propellers), power conversion unit  415  may be rotated through 90 degrees to accomplish a complete thrust reversal. Power conversion unit  415  may be configured with, for example, vanes, ports, and/or other devices, such that a thrust generated by power conversion unit  415  may be modified and directed in a desired direction. Alternatively (or in addition), direction of thrust associated with power conversion unit  415  may be accomplished via manipulation of propulsion unit mount  430 . 
     As shown in  FIG. 9 , for example, propulsion unit mount  430  may be operatively connected to support structure  20  and may be configured to hold a power source  410  securely, such that forces associated with propulsion assemblies  31  may be transferred to support structure  20 . For example, propulsion unit mount  430  may include fastening points  455  designed to meet with a fastening location on a suitable portion of support structure  20  of hull  12 . Such fastening locations may include structural reinforcement for assistance in resisting forces associated with propulsion assemblies  31  (e.g., thrust forces). Additionally, propulsion unit mount  430  may include a series of fastening points designed to match fastening points on a particular power source  410 . One of ordinary skill in the art will recognize that an array of fasteners may be used for securing fastening points to obtain a desired connection between propulsion unit mount  430  and a fastening location. 
     According to some embodiments, propulsion unit mount  430  may include pivot assemblies configured to allow a rotation of propulsion assemblies  31  about one or more axes (e.g., axes  465  and  470 ) in response to a control signal provided by, for example, computer  600  (see, e.g.,  FIG. 30 ). 
       FIGS. 10 and 11B  illustrate exemplary configurations (viewed from the bottom of airship  10 ) of a propulsion system associated with airship  10  consistent with the present disclosure. Propulsion assemblies  31  associated with airship  10  may be configured to provide a propulsive force (e.g., thrust), directed in a particular direction (i.e., a thrust vector), and configured to generate motion (e.g., horizontal motion), counteract a motive force (e.g., wind forces), and/or other manipulation of airship  10  (e.g., yaw control). For example, propulsion assemblies  31  may enable yaw, pitch, and roll control as well as providing thrust for horizontal and vertical motion. Such functionality may depend on placement and power associated with propulsion assemblies  31 . 
     Functions associated with propulsion system  30  may be divided among a plurality of propulsion assemblies  31  (e.g., five propulsion assemblies  31 ). For example, propulsion assemblies  31  may be utilized for providing a lift force for a vertical take-off such that the forces of the lighter-than-air gas within first envelope  282  are assisted in lifting by a thrust force associated with the propulsion assemblies  31 . Alternatively (or in addition), propulsion assemblies  31  may be utilized for providing a downward force for a landing maneuver such that the forces of the lighter-than-air gas within first envelope  282  are counteracted by a thrust force associated with the propulsion assemblies  31 . In addition, horizontal thrust forces may also be provided by propulsion assemblies  31  for purposes of generating horizontal motion (e.g., flying) associated with airship  10 . 
     It may be desirable to utilize propulsion assemblies  31  for controlling or assisting in control of yaw, pitch, and roll associated with airship  10 . For example, as shown in  FIG. 10 , propulsion system  30  may include a fore propulsion assembly  532  operatively affixed to a fore section of keel hoop  120  and substantially parallel to and/or on roll axis  5  of airship  10 . In addition to fore propulsion assembly  532 , propulsion system  30  may include a starboard propulsion assembly  533  operatively affixed to keel hoop  120  at approximately 120 degrees (about yaw axis  7 ) relative to roll axis  5  of airship  10  and a port propulsion assembly  534  operatively affixed to keel hoop  120  at approximately negative 120 degrees (e.g., positive 240 degrees) (about yaw axis  7 ) relative to roll axis  5  of airship  10 . Such a configuration may enable control of yaw, pitch, and roll associated with airship  10 . For example, where it is desired to cause a yawing movement of airship  10 , fore propulsion assembly  532  may be rotated or pivoted such that a thrust vector associated with fore propulsion assembly  532  is directed parallel to pitch axis  6  and to the right or left relative to hull  12 , based on the desired yaw. Upon operation of fore propulsion assembly  532 , airship  10  may be caused to yaw in reaction to the directed thrust associated with fore propulsion assembly  532 . 
     In other exemplary embodiments, for example, where it is desired to cause a pitching motion associated with airship  10 , fore propulsion assembly  532  may be rotated such that a thrust force associated with fore propulsion assembly  532  may be directed parallel to yaw axis and toward the ground (i.e., down) or toward the sky (i.e., up), based on the desired pitch. Upon operation of fore propulsion assembly  532 , airship  10  may then be caused to pitch in reaction to the directed thrust associated with fore propulsion assembly  532 . 
     According to still other embodiments, for example, where it is desired to cause a rolling motion associated with airship  10 , starboard propulsion assembly  533  may be rotated such that a thrust force associated with starboard propulsion assembly  533  may be directed parallel to yaw axis  7  and toward the ground (i.e., down) or toward the sky (i.e., up) based on the desired roll, and/or port propulsion assembly  534  may be rotated such that a thrust force associated with port propulsion assembly  534  may be directed in a direction opposite from the direction of the thrust force associated with starboard propulsion assembly  533 . Upon operation of starboard propulsion assembly  533  and port propulsion assembly  534 , airship  10  may then be caused to roll in reaction to the directed thrusts. One of ordinary skill in the art will recognize that similar results may be achieved using different combinations and rotations of propulsion assemblies  31  without departing from the scope of the present disclosure. 
     Fore, starboard, and port propulsion assemblies  532 ,  533 , and  534  may also be configured to provide thrust forces for generating forward or reverse motion of airship  10 . For example, starboard propulsion unit  533  may be mounted to propulsion mount  430  and configured to pivot from a position in which an associated thrust force is directed in a downward direction (i.e., toward the ground) to a position in which the associated thrust force is directed substantially parallel to roll axis  5  and toward the rear of airship  10 . This may allow starboard propulsion unit  533  to provide additional thrust to supplement thrusters. Alternatively, starboard propulsion unit  534  may be rotated from a position in which an associated thrust force is directed substantially parallel to roll axis  5  and toward the rear of airship  10 , to a position where the associated thrust force is directed along pitch axis  6  such that an adverse wind force may be counteracted. 
     In addition to fore, starboard, and port propulsion assemblies  532 ,  533 , and  534 , respectively, propulsion system  30  may include one or more starboard thrusters  541  and one or more port thruster  542  configured to provide horizontal thrust forces to airship  10 . Starboard and port thrusters  541  and  542  may be mounted to keel hoop  120 , lateral frame members  122 , horizontal stabilizing members  315 , or any other suitable location associated with airship  10 . Starboard and port thrusters  541  and  542  may be mounted using an operative propulsion unit mount  430  similar to that described above, or, alternatively, starboard and port thrusters  541  and  542  may be mounted such that minimal rotation or pivoting may be enabled (e.g., substantially fixed). For example, starboard and port thrusters  541  and  542  may be mounted to keel hoop  120  at an aft location on either side of vertical stabilizing member  310  (e.g., at approximately 160 degrees and negative 160 degrees, as shown in  FIG. 5B ). In some embodiments, starboard and port thrusters  541  and  542  may be substantially co-located with starboard and port propulsion assemblies  533  and  534  as described above (e.g., positive 120 degrees and negative 120 degrees). In such embodiments, propulsion unit mounts  430  associated with starboard and port propulsion assemblies  533  and  534  may include additional fastening points such that propulsion unit mounts  430  associated with starboard and port thrusters  541  and  542  may be operatively connected to one another. Alternatively, propulsion unit mounts  430  associated with starboard and port thrusters  541  and  542  may be operatively connected to substantially similar fastening points on support structure  20  as fastening points connected to propulsion unit mounts  430  associated with starboard and port propulsion assemblies  533  and  534 . 
     In some embodiments, thrust from starboard and port thrusters  541  and  542  may be directed along a path substantially parallel to roll axis  5 . Such a configuration may enable thrust forces associated with starboard and port thrusters  541  and  542  to drive airship  10  in a forward or reverse direction based on the thrust direction. 
     In some embodiments, thrust from starboard and port thrusters  541  and  542  may be configurable based on a position of associated propulsion unit mount  430 . One of ordinary skill in the art will recognize that additional configurations for starboard and port thrusters  541  and  542  may be utilized without departing from the scope of this disclosure. 
     Power Supply System 
     As shown in  FIG. 12A , power supply system  1000  may include one or more solar energy converting devices, such as solar panels  1010  (including photovoltaic cells) disposed on airship  10 . Solar panels  1010  may be disposed on various portions of airship  10  in a variety of different configurations. Airship  10  may include an additional or alternative solar energy converting device, such as a photovoltaic fabric. For example, in some embodiments, one or more portions of hull  12  may include a photovoltaic fabric. In one exemplary embodiment, an entire upper surface of hull  12  may include a photovoltaic fabric.  FIG. 12B  depicts an exemplary embodiment of airship  10 , wherein the entire upper surface of hull  12  forms a solar energy converting device, e.g., either a solar panel or photovoltaic fabric. 
     Persons of ordinary skill in the art will recognize the requirements of solar panels suitable for the applications disclosed herein. Further, the disclosed configurations and placement of solar panels shown and discussed herein are not intended to be limiting, and persons of ordinary skill in the art will understand that additional embodiments are possible. 
     Solar panels  1010  may be operatively coupled to one or more electric motors  1020 , and configured to supply power to one or more electric motors  1020  for driving power conversion units  415 . In addition, power supply system  1000  may include one or more batteries  1030  operatively coupled to solar panel  1010  and configured to receive and store electrical energy supplied by solar panel  1010 , and may further be operatively coupled to electric motors  1020  to supply power to electric motors  1020 . 
     Batteries  1030  may each be located within an outer envelope of airship  10  defined by hull  12  of airship  10 . Batteries  1030  may be disposed in respective positions providing ballast. 
     Persons of ordinary skill in the art will recognize suitable operative connections between solar panel  1010 , batteries  1030 , and electric motors  1020 , according to the arrangements described above. 
     Cargo System 
     As used herein, the term “cargo” is intended to encompass anything carried by airship  10  that is not a part of airship  10 . For example, the term “cargo,” as used herein, refers to freight, as well as passengers. Further, the term “passengers” is intended to encompass not only persons along for the ride, but also pilots and crew. 
     As shown in  FIGS. 13A-13B , airship  10  may include a cargo system  1100 , which may include at least one cargo compartment  1110  configured to contain passengers and/or freight, and disposed substantially within the outer envelope of the airship, which is defined by hull  12 . In some embodiments, airship  10  may include multiple cargo compartments  1110  as shown in the accompanying figures. Cargo compartments  1110  may be of any suitable size and/or shape, and may include, for example, a passenger compartment  1120 , which may include a pilot cockpit and/or accommodations (e.g., seating and/or lodging) for commercial travelers/tourists. In some embodiments, cargo compartments  1110  may include a freight compartment  1130 . In some embodiments, airship  10  may include a passenger compartment  1120  and a separate freight compartment  1130 . 
     Although the figures show cargo compartments  1110  generally disposed in the bottom portion of airship  10  and having a lower surface that conforms to, or is substantially continuous with, the envelope defined by hull  12 , cargo compartments  1110  may have any suitable shape. Further, cargo compartments  1110  may be disposed in a location other than the bottom of airship  10 . For example, embodiments are envisioned that include a passenger compartment disposed near the top portion of hull  12 . Such embodiments may be practical, for example, if the passenger compartment is relatively small, e.g., to only hold a flight crew and/or several passengers. 
     In some embodiments, cargo compartments  1110  may be relatively small compared to the overall size of airship  10 , as shown in  FIG. 13A . Alternatively, cargo compartments  1110  may be significantly larger. 
     Persons of ordinary skill in the art will recognize that the size, shape, and location may be selected according to numerous parameters related to the intended operation of the airship, such as weight, ballast, desired lifting gas volume (since the internally-located cargo compartments come at the expense of lifting gas volume), etc. For example, in some embodiments one or more of cargo compartments  1110  may be disposed at a location such that a static equilibrium associated with airship  10  may be maintained. In such embodiments, a cargo compartment  1110  may be mounted, for example, at a location along roll axis  5 , such that a moment about pitch axis  6  associated with the mass of the cargo compartment (or the mass of the cargo compartment including contents having a predetermined mass) substantially counteracts a moment about pitch axis  6  associated with the mass of empennage assembly  25 . Furthermore, the placement of cargo compartments  1110  within the envelope of hull  12 , places the mass of cargo compartments  1110  and any contents therein closer to both roll axis  5  and pitch axis  6 , thus reducing moments associated with placement of such mass at distances from these axes. Similarly, positioning of cargo compartments  1110  relative to yaw axis  7  may also be taken into consideration. 
     In some embodiments, cargo compartments  1110  may include a suitable means of access, such as a ladder, stairs, or ramp. In other embodiments, at least one cargo compartment  1110  of airship  10  may include a transport system  1140  configured to lower and raise at least a portion of cargo compartment  1110  to facilitate loading and unloading of cargo compartment  1110 . 
     Bladders 
     Airship  10  may include one or more bladders  1200  inside hull  12  for containing a lighter-than-air gas, as shown in  FIG. 14 . In some embodiments, airship  10  may include multiple bladders  1200  disposed within hull  12  in a side-by-side, end-to-end, and/or stacked configuration.  FIG. 14  illustrates an exemplary embodiment having four bladders  1200  disposed in four quadrants of hull  12 . Other configurations for bladders  1200  are also possible. 
     In some embodiments, bladders  1200  may be formed of a self-sealing material. As discussed above with respect to hull  12 , persons of ordinary skill in the art will recognize self-sealing technologies suitable for implementation in bladders  1200 . 
     As an alternative to, or in addition to, multiple bladders  1200 , envelope  282  associated with hull  12  may be divided by a series of “walls” or dividing structures (not shown) within envelope  282 . These walls may create separated “compartments” that may each be filled with a lighter-than-air lifting gas individually. Such a configuration may mitigate the consequences of the failure of one or more compartments (e.g., a leak or tear in the fabric) such that airship  10  may still possess some aerostatic lift upon failure of one or more compartments. In some embodiments, each compartment may be in fluid communication with at least one other compartment, and such walls may be fabricated from materials similar to those used in fabrication of envelope  282 , or, alternatively (or in addition), different materials may be used. According to some embodiments, envelope  282  may be divided into four compartments using “walls” created from fabric similar to that used to create envelope  282 . One of skill in the art will recognize that more or fewer compartments may be utilized as desired. 
     One or more of the compartments or bladders  1200  within envelope  282  may include one or more fill and/or relief valves (not shown) configured to facilitate inflation, while minimizing the risk of over-inflation of envelope  282  and/or bladders  1200 . Such valves may be designed to allow entry of a lighter-than-air gas as well as allowing escape of lighter-than-air gas upon an internal pressure reaching a predetermined value (e.g., about 150 to 400 Pascals). One of skill in the art will recognize that more or fewer fill/relief valves may be used as desired and that relief pressures may be selected based on materials associated with envelope  282  and/or bladders  1200 , among other things. 
     Airship  10  may also include a second envelope  283  (see  FIG. 3 ), thus defining a space between first envelope  282  and second envelope  283 , which may be utilized as a ballonet for airship  10 . For example, a ballonet may be used to compensate for differences in pressure between a lifting gas within first envelope  282  and the ambient air surrounding airship  10 , as well as for ballasting of an airship. The ballonet may therefore allow hull  12  to maintain its shape when ambient air pressure increases (e.g., when airship  10  descends). The ballonet may also help control expansion of the lighter-than-air gas within first envelope  282  (e.g., when airship  10  ascends), substantially preventing bursting of first envelope  282  at higher altitudes. Pressure compensation may be accomplished, for example, by pumping air into, or venting air out of, the ballonet as airship  10  ascends and descends, respectively. Such pumping and venting of air may be accomplished via air pumps, vent tabs, or other suitable devices (e.g., action of the propulsion system  30 ) associated with hull  12 . For example, in some embodiments, as airship  10  ascends, air pumps (e.g., an air compressor) may fill the space between first envelope  282  and second envelope  283  with air such that a pressure is exerted on first envelope  282 , thereby restricting its ability to expand in response to decreased ambient pressure. Conversely, as airship  10  descends, air may be vented out of the ballonet, thereby allowing first envelope  282  to expand and assisting hull  12  in maintaining its shape as ambient pressure increases on hull  12 . 
     Empennage Assembly 
       FIG. 15A  illustrates an exemplary empennage assembly  25 . Empennage assembly  25  may be configured to provide stabilization and/or navigation functionality to airship  10 . Empennage assembly  25  may be operatively connected to support structure  20  via brackets, mounts, and/or other suitable methods. For example, in some embodiments, an empennage mount  345  similar to that shown in  FIG. 15B  may be used for operatively connecting empennage assembly  25  to longitudinal frame member  124  and keel hoop  120  (see  FIGS. 2 and 15D ). 
       FIG. 15D  is a schematic view highlighting an exemplary mounting configuration between empennage  25 , keel hoop  120 , and longitudinal support member  124 , utilizing empennage mount  345 . One of ordinary skill in the art will recognize that numerous other mounting configurations may be utilized and are intended to fall within the scope of the present disclosure. 
     According to some embodiments, as shown in  FIGS. 15A and 15D , empennage assembly  25  may include a vertical stabilizing member  310  and horizontal stabilizing members  315 . Vertical stabilizing member  310  may be configured as an airfoil to provide airship  10  with stability and assistance in yaw/linear flight control. Vertical stabilizing member  310  may include a leading edge, a trailing edge, a pivot assembly, one or more spars, and one or more vertical control surfaces  350  (e.g., a rudder). 
     Vertical stabilizing member  310  may be pivotally affixed to a point on empennage assembly  25 . During operation of airship  10 , vertical stabilizing member  310  may be directed substantially upward from a mounting point of empennage assembly  25  to support structure  20  while the upper-most point of vertical stabilizing member  310  remains below or substantially at the same level as the uppermost point on the top surface of hull  12 . Such a configuration may allow vertical stabilizing member  310  to maintain isotropy associated with airship  10 . Under certain conditions (e.g., free air docking, high winds, etc.), vertical stabilizing member  310  may be configured to pivot about a pivot assembly within a vertical plane such that vertical stabilizing member  310  comes to rest in a horizontal or downward, vertical direction, and substantially between horizontal stabilizing members  315 . Such an arrangement may further enable airship  10  to maximize isotropy relative to a vertical axis, thereby minimizing the effects of adverse aerodynamic forces, such as wind cocking with respect to vertical stabilizing member  310 . In some embodiments consistent with the present disclosure, where hull  12  includes a thickness dimension of 7 meters and where empennage assembly  25  is mounted to keel hoop  120  and longitudinal frame member  124 , vertical stabilizing member  310  may have a height dimension ranging from about 3 meters to about 4 meters. 
     Vertical stabilizing member  310  may also include one or more vertical control surfaces  350  configured to manipulate airflow around vertical stabilizing member  310  for purposes of controlling airship  10 . For example, vertical stabilizing member  310  may include a rudder configured to exert a side force on vertical stabilizing member  310  and thereby, on empennage mount  345  and hull  12 . Such a side force may be used to generate a yawing motion about yaw axis  7  of airship  10 , which may be useful for compensating for aerodynamic forces during flight. Vertical control surfaces  350  may be operatively connected to vertical stabilizing member  310  (e.g., via hinges) and may be communicatively connected to systems associated with a pilot cockpit (e.g., operator pedals) or other suitable location. For example, communication may be established mechanically (e.g., cables) and/or electronically (e.g., wires and servo motors  346  and/or light signals) with the cockpit or other suitable location (e.g., remote control). In some embodiments, vertical control surfaces  350  may be configured to be operated via a mechanical linkage  351 . In some cases, mechanical linkage  351  may be operably connected to one or more servo motors  346 , as shown in  FIGS. 15A and 15D . 
     Horizontal stabilizing members  315  associated with empennage assembly  25  may be configured as airfoils and may provide horizontal stability and assistance in pitch control of airship  10 . Horizontal stabilizing members  315  may include a leading edge, a trailing edge, one or more spars, and one or more horizontal control surfaces  360  (e.g., elevators). 
     In some embodiments, horizontal stabilizing members  315  may be mounted on a lower side of hull  12  in an anhedral (also known as negative or inverse dihedral) configuration. In other words, horizontal stabilizing members  315  may extend away from vertical stabilizing member  310  at a downward angle relative to roll axis  5 . The anhedral configuration of horizontal stabilizing members  315  may allow horizontal stabilizing members  315  to act as ground and landing support for a rear section of airship  10 . Alternatively, horizontal stabilizing members  315  may be mounted in a dihedral or other suitable configuration. 
     According to some embodiments, horizontal stabilizing members  315  may be operatively affixed to empennage mount  345  and/or vertical stabilizing member  310  independent of hull  12 . Under certain conditions (e.g., free air docking, high winds, etc.) empennage assembly  25  may be configured to allow vertical stabilizing member  310  to pivot within a vertical plane, such that vertical stabilizing member  310  comes to rest substantially between horizontal stabilizing members  315 . 
     Horizontal stabilizing members  315  may also include one or more horizontal control surfaces  360  (e.g., elevators) configured to manipulate airflow around horizontal stabilizing members  315  to accomplish a desired effect. For example, horizontal stabilizing members  315  may include elevators configured to exert a pitching force (i.e., up or down force) on horizontal stabilizing members  315 . Such a pitching force may be used to cause motion of airship  10  about pitch axis  6 . Horizontal control surfaces  360  may be operatively connected to horizontal stabilizing members  315  (e.g., via hinges) and may be mechanically (e.g., via cables) and/or electronically (e.g., via wires and servo motors  347  and/or light signals) controlled from a pilot cockpit or other suitable location (e.g., remote control). In some embodiments, horizontal control surfaces  360  may be configured to be operated via a mechanical linkage  349 . In some cases, mechanical linkage  349  may be operably connected to one or more servo motors  347 , as shown in  FIG. 15A . 
       FIG. 15B  is an illustration of an exemplary embodiment of empennage mount  345 . Empennage mount  345  may be configured to operatively connect vertical stabilizing member  310 , horizontal stabilizing members  315 , and support structure  20 . Empennage mount  345  may include similar high-strength, low-weight materials discussed with reference to support structure  20  (e.g., carbon fiber honeycomb sandwich). Further, empennage mount  345  may include fastening points configured to mate with fastening points present on support structure  20 . For example, longitudinal frame member  124  and/or keel hoop  120  may be configured with fastening points near a rear location of keel hoop  120  (e.g., at approximately 180 degrees around keel hoop  120 ). Such fastening points may be configured to mate with fastening points provided on empennage mount  345 . One of ordinary skill in the art will recognize that numerous fastener combinations may be utilized for fastening empennage mount  345  to the related fastening points of heel hoop  220  and longitudinal frame member  124 . 
     Empennage mount  345  may include pins, hinges, bearings, and/or other suitable devices to enable such a pivoting action. In some embodiments, vertical stabilizing member  310  may be mounted on a swivel pin (not shown) associated with empennage mount  345  and may include a latching mechanism (not shown) configured to operatively connect vertical stabilizing member  310  to keel hoop  120  and/or other suitable location. Latching mechanism (not shown) may include hawksbill latches, slam latches, spring loaded pins, striker plates, hydraulic actuators, and/or any other combination of suitable mechanisms. Control of latching mechanism (not shown) and pivoting of vertical stabilizing member  310  may be achieved utilizing mechanical (e.g., via cables) and/or electrical (e.g., via control signals and servo motors), or any other suitable control methods (e.g., via hydraulics). 
     Rear Landing Gear 
     When, for example, horizontal stabilizing members  315  are configured in an anhedral arrangement (i.e., angled downward away from hull  12 ) and are connected to a lower side of airship  10 , horizontal stabilizing members  315  may function as ground and landing support for a rear section of airship  10 . Accordingly, empennage assembly  25 , specifically horizontal stabilizing members  315  may provide support for rear landing gear assembly  377 . 
     Rear landing gear assembly  377  may be operatively connected to each airfoil associated with horizontal stabilizing members  315  (e.g., as shown in  FIG. 15C ). Rear landing gear assembly  377  may include one or more wheels  378 , one or more shock absorbers  381 , and mounting hardware  379 . Rear landing gear assemblies  377  may be connected to horizontal stabilizing members  315  at a tip end and/or any other suitable location (e.g., a midpoint of horizontal stabilizing members  315 ). 
     In some embodiments, rear landing gear assembly  377  may include a single wheel mounted on an axle operatively connected via oleo-pneumatic shock-absorbers to horizontal stabilizing members  315  at an outer-most tip of each airfoil. Such a configuration may allow rear landing gear assembly  377  to provide a damping force in relation to an input (e.g., forces applied during touchdown and landing). Horizontal stabilizing member  315  may further assist in such damping based on configuration and materials used. One of ordinary skill in the art will recognize that rear landing gear assemblies  377  may include more or fewer elements as desired. 
     Rear landing gear assembly  377  may be configured to perform other functions including, for example, retracting and extending (e.g., with respect to horizontal stabilizing members  315 ), and/or adjusting for a load associated with airship  10 . One of ordinary skill in the art will recognize that numerous configurations may exist for rear landing gear assembly  377  and any such configuration is meant to fall within the scope of this disclosure. 
     Front Landing Gear 
     According to some embodiments, support structure  20  may be configured to provide support as well as an operative connection to front landing gear assembly  777  (see  FIG. 8 ). Front landing gear assembly  777  may include one or more wheels, one or more shock absorbers, and mounting hardware. Front landing gear assembly  777  may be connected to support structure  20  at a location configured to provide stability during periods when airship  10  is at rest or taxiing on the ground. One of ordinary skill in the art will recognize that various positioning configurations of front landing gear assembly  777  (e.g., in front of passenger compartment  1120 ) may be used without departing from the scope of this disclosure. In some embodiments, front landing gear  777  may include dual wheels mounted on an axle operatively connected via oleo-pneumatic shock-absorbers to support structure  20  or passenger compartment  1120 . 
     In some embodiments, front landing gear assembly  777  may be mounted on passenger compartment  1120 , and may be deployed by virtue of the extension/lowering of passenger compartment  1120 , as shown in  FIG. 16 . 
     According to some embodiments, front landing gear assembly  777  may be configured to perform other functions including, for example, steering airship  10  while on the ground, retracting, extending, adjusting for load, etc. For example, front landing gear assembly  777  may include an operative connection to passenger compartment  1120  such that front landing gear assembly  777  may be turned to cause airship  10  to head in a desired direction while moving on the ground. Such a connection may include a rack and pinion, a worm gear, an electric motor, and/or other suitable devices for causing front landing gear assembly  777  to turn in response to a steering input. 
     According to some embodiments, front landing gear assembly  777  may include an operative connection to a steering control associated with a yoke in passenger compartment  1120 . An operator may turn the yoke causing a signal indicative of a steering force to be sent to computer  600 . Computer  600  may then cause an electric motor associated with front landing gear assembly  777  to cause front landing gear assembly  777  to turn in a direction indicated by the steering force input from the operator. Alternatively, steering may be accomplished via a mechanical connection (e.g., cables, hydraulics, etc.) or any other suitable method. One of ordinary skill in the art will recognize that a steering control may be linked to flight controls, a dedicated steering control, and/or other suitable control without departing from the scope of the present disclosure. 
     Aerodynamic Components 
     According to some embodiments, hull  12  may include one or more aerodynamic components  2000  to provide stabilization of airship  10 . Aerodynamic components  2000  may be associated with hull  12  and may be configured to direct airflow along airship  10 . For example, in some embodiments, as shown in  FIG. 1 , aerodynamic components  2000  may include one or more fairing structures such as, for example, a plurality of slats  2010  separating and/or defining a plurality of parallel airflow passages  2020 . As shown in  FIG. 1 , in some embodiments, passages  2020  may also be defined by covers  2012  and an outer surface of hull  12 . Slats  2010  may be arranged in any suitable direction, for example, with a fore-aft orientation and/or a port-starboard orientation. Further, slats  2010  may be disposed on a top portion of hull  12 , as shown in  FIG. 1 , and/or on a bottom portion of hull  12 , as shown in  FIG. 17 . Also, the amount of surface area covered by aerodynamic components  2000  may be selected based on the anticipated use and/or environment in which airship  10  may be used. In some embodiments, the width of an aerodynamic component may span substantially the entire width of airship  10 , as shown for example in  FIG. 18 . In other embodiments, the width of an aerodynamic component may span a distance that is less than the full width of airship  10 , as shown in  FIG. 1 . 
     In some embodiments, multiple aerodynamic components  2000  may be disposed separately on hull  12 , as shown for example in  FIG. 1 .  FIG. 1  shows an exemplary configuration wherein a longitudinally-oriented aerodynamic component  2000  is disposed centrally on the top portion of hull  12 , and transversely-oriented aerodynamic components  2000  are disposed fore and aft of the centrally-mounted, longitudinally-oriented aerodynamic component  2000 . 
     Alternatively, or additionally, two or more aerodynamic components  2000  may abut one another and/or overlap one another, as shown in  FIG. 19 . For example,  FIG. 19  shows an exemplary configuration wherein a transversely-oriented aerodynamic component  2000  is disposed partially below a centrally-disposed, longitudinally-oriented aerodynamic component  2000 . 
     Aerodynamic component  2000  may be configured to minimize the susceptibility of airship  10  to winds passing over airship  10  off-axis with respect to aerodynamic component  2000 , that is, in a direction that is not aligned (i.e., not parallel) with slats  2010 . For example, in some embodiments, slats  2010  may be integrated into hull  12 , such that the surface shape of hull  12  remains unchanged, and aerodynamic component  2000  may be exposed to airflow by a relatively small opening in hull  12 , as shown in  FIG. 19 . In other embodiments, aerodynamic component  2000  may protrude from the contour of hull  12 , but may still have a relatively low profile and smooth transition from hull  12  so as to limit the amount of drag created by aerodynamic component  2000  in off-axis directions. (See, e.g.,  FIG. 1 .) In other embodiments, hull  12  may have a second skin within which aerodynamic components  2000  may be integrated, as shown for example, in  FIG. 20 . 
     Slats  2010  may be made of any suitable material. In some embodiments, slats  2010  may be formed of a rigid material, such as plastic, carbon fiber, aluminum, titanium, etc. Some embodiments may alternatively, or additionally, include slats  2010  formed of a flexible material, such as a fabric, e.g., the same fabric that may be used to form hull  12 , Slats  2010  may have a uniform cross sectional shape along the length thereof, e.g., a thin-walled partition. Some embodiments may include slats  2010  having a non-uniform cross-sectional shape. For example, slats  2010  may have an airfoil shape (e.g., in a fore-aft direction), or a modified airfoil shape, such as a kamm tail. 
     In some embodiments, slats  2010  may be parallel, as shown in  FIG. 1 . Alternatively, or additionally, airship  10  may include slats  2010  having a different configuration. For example, slats  2010  may be arranged in an alternating diagonal configuration, as shown in  FIG. 21 . In embodiments wherein slats  2010  are rigid, the alternating diagonal configuration may provide enhanced structural support, as it may form a truss-like structure. 
     Aerodynamic components  2000  may include inside wall surfaces of airflow passages  2020  that may be substantially planar, or may be curved. In some embodiments, as shown in  FIG. 20 , an upper wall  2030  may be the underside of a top portion  2040  of hull  12 , and thus, may be curved upward. In other embodiments, as shown in  FIG. 22 , upper surface  2030  may be substantially planar (e.g., horizontal, or in any plane deemed suitable). In some embodiments, upper surface  2030  may be substantially planar, and a front edge  2050  of aerodynamic component  2000  may have a curvature such that the portion of hull  12  between airflow passages  2020  and top portion  2040  of hull  12  may have an asymmetrical airfoil cross-sectional shape, as shown in  FIG. 22 . This configuration may create aerodynamic lift, during flight. In such embodiments, a bottom side aerodynamic component  2000  may be disposed on a bottom portion  2060  of airship  10 , and the cross-sectional shape of the hull portion between airflow passages  2020  of bottom side aerodynamic component  2000  and a bottom surface  2070  of hull  12  may have a substantially symmetrical cross sectional shape (by virtue of a curved lower wall  2080  and similarly curved bottom surface  2070 ) so as to prevent a counteracting aerodynamic force from canceling out the aerodynamic lift created by aerodynamic component  2000  on the upper portion of airship  10 . Further, in some embodiments, the narrowed airflow passage  2020  created by curved lower wall  2080  at bottom portion  2060  may accelerate airflow compared to airflow passing across the underside of bottom surface  2070 , thereby creating additional aerodynamic lift. 
       FIG. 23  illustrates a cutaway, perspective view of an airship having an embodiment of aerodynamic components  2000  similar to that shown in  FIG. 20 . For example, like the embodiment shown in  FIG. 23 ,  FIG. 20  shows an embodiment wherein fore and aft aerodynamic components  2000  are disposed in a lateral orientation and reside at least partially under a centrally-disposed aerodynamic component  2000  having a longitudinal (i.e., fore-aft) orientation. 
       FIG. 24  illustrates a similar embodiment to that shown in  FIG. 20 , except that the orientation of aerodynamic components  2000  is reversed. In the embodiment shown in  FIG. 24 , the centrally-disposed aerodynamic component  2000  has a port-starboard orientation (allowing lateral air flow), and fore-aft flow of air is allowed through laterally-disposed aerodynamic components  2000  that are overlapped by the centrally-disposed aerodynamic component  2000 . 
     Floatation Structures 
     According to some embodiments, airship  10  may include at least one floatation structure  4000  configured to support airship  10  for floatation on water during a water landing. In some embodiments, hull  12  may include a floatation structure. For example, as shown in  FIG. 25 , in some embodiments, hull  12  may include an enlarged lower portion configured to provide buoyancy. In such embodiments, hull  12  may be formed of a lightweight material, such as carbon fiber. Further, hull  12  may be a hollow structure or may be filled with a lightweight material, such as a foam, or a honeycomb structure. Also, in such embodiments, airship  10  may include additional floatation structures  4000 , such as outboard pontoons  4010 , attached, for example, to horizontal stabilizing members  315 , as shown in  FIG. 25 . Outboard pontoons  4010  may be configured to provide stability to airship  10  while floating. 
     In some embodiments, airship  10  may include multiple sets of floatation structures  4000 . For example, as shown in  FIG. 26 , airship  10  may include outboard pontoons  4010  mounted to horizontal stabilizing members  315 , as well as one or more main pontoons  4020  mounted to hull  12 , e.g., by pontoon support members  4030 . Main pontoons  4020  may be formed of the same or similar materials as discussed above with respect to outboard pontoons  4010 . In some embodiments, outboard pontoons  4010  and/or main pontoons  4020  may have a shape similar to pontoons known to be used for a winged aircraft. Such pontoons may be formed with a boat hull-like configuration to facilitate forward travel while afloat (e.g., during takeoff and landing). In other embodiments, outboard pontoons  4010  and/or main pontoons  4020  may have a more simplistic shape. For example, when airship  10  is anticipated to be used exclusively as a VTOL aircraft, the pontoons may be configured for maximum buoyancy, as opposed to travel through water. 
     As shown in  FIGS. 27 and 28 , airship  10  may include deployable floatation structures  4000 . For example, airship  10  may include deployable main pontoons  4040 , which may be formed of a portion of hull  12  that may be extended to an outboard position, which is illustrated by broken lines in  FIGS. 27 and 28 . In some embodiments, deployable main pontoons  4040  may be extendable in a downward direction, as shown in  FIG. 27 . In other embodiments, deployable main pontoons  4040  may be extendable downward and laterally outward from roll axis  5 , as shown in  FIG. 28 , providing a wide, stable stance. As also shown in  FIG. 28 , deployable outboard pontoons  4050  may be extendable beyond the distal tips of horizontal stabilizing members  315 , to provide additional stability. 
     Deployable pontoons may be formed with surface aspects of a hydrofoil. In some embodiments, outboard pontoons  4010 , main pontoons  4020 , deployable main pontoons  4040 , and/or deployable outboard pontoons  4050  may be formed with a cross-sectional shape similar to catamaran-style hydroplane race boat hulls, as shown, for example, in  FIG. 27 . 
     Deployable Apparatus 
     According to some embodiments, airship  10  may include a deployable apparatus  5000 . Deployable apparatus  5000  may be housed within hull  12  and deployable from hull  12  for operation unrelated to the flight control or landing of airship  10 . For example, as shown in  FIG. 29 , airship  10  may include a drilling apparatus  5010  that may be deployed from hull  12 . A storage area within hull  12  may be configured to house components of drilling apparatus  5010 , such as sections of drilling shaft. In some embodiments, storage area doors may be opened to expose deployable apparatus  5000 . Alternatively, as illustrated in  FIG. 29 , deployable main pontoons  4040  may serve as the storage area doors, and drilling apparatus  5010  may when deployable main pontoons  4040  are deployed. 
     Flight control systems of airship  10  may be configured to maintain airship  10  stationary and stable during drilling operations. In some embodiments, airship  10  may include anchor-like devices (not shown), which may fix airship  10  to the sea floor, either via a tether or a more rigid attachment. In some embodiments, airship  10  may be maintained stationary via operation of the flight control system and/or using sea floor fixation, in such a manner to facilitate oil and/or natural gas drilling operations, or operations to harvest other natural resources. 
     In some embodiments, airship  10  may be suited for relatively shallow water drilling. Further, deployable apparatus  5000  may also be incorporated in an embodiment of airship  10  equipped for ground landing (as opposed to water landing). Also, in some embodiments, airship  10  may be configured for drilling shallow holes. For example, a suitable application may include drilling of holes for installation and/or construction of support pylons. Other types of apparatus may be deployable from airship  10 . Such apparatuses may include, for example, construction equipment, demolition equipment, firefighting equipment, lifting and transportation equipment (e.g., a forklift-type apparatus), aircraft and/or watercraft refueling equipment, water removal/pumping equipment, weather monitoring equipment, etc. 
     INDUSTRIAL APPLICABILITY 
     The disclosed airship  10  may be implemented for use in a wide range of applications. For example, in some embodiments, airship  10  may be configured to perform functions involving traveling from one location to another. For instance, airship  10  may be configured to perform a function associated with at least one of lifting objects (e.g., construction lifting), elevating a platform, transporting items (e.g., freight), displaying items (e.g., advertisement), transporting humans (e.g., passenger carriage and/or tourism), and/or providing recreation. 
     Exemplary applications for disclosed airship  10  may include transporting equipment and/or supplies, such as construction equipment or building components. For example, airship  10  may be used to transport oil pipeline construction equipment, as well as the piping itself. Airship  10  may be applicable for use in connection with building, operating, and/or maintaining pipelines, as well as logging and transportation of timber. Such applications may have particular use in remote areas, e.g., without transportation infrastructure, such as roads or airstrips, e.g., in Alaska, Canada, the Australian outback, the middle east, Africa, etc. Exemplary such areas may include tundra, desert, glaciers, snow and/or ice-covered land bodies, etc. 
     Another exemplary use of airship  10  may include crop dusting. Embodiments of airship  10  having engine configurations as disclosed herein may be capable of high levels of accuracy with respect to delivery of crop treatments. Advantages of such high accuracy may include the ability to dust crops in one plot of land without resulting in drift of sprayed chemicals onto neighboring plots. This may be advantageous when nearby plots include differing types of crops and/or if the nearby plots are, for example, maintained as organic. 
     In some embodiments, airship  10  may be configured to perform functions wherein the airship remains in substantially stationary flight. For example, airship  10  may be configured to perform a function including at least one of assembly of a structure, conducting cellular communications, conducting satellite communications, conducting surveillance, advertising, conducting scientific studies, and providing disaster support services. Airship  10  may include a platform or other cargo carrying structure configured to suspend communications equipment (e.g., satellite relay/receiver, cell tower, etc.) over a particular location. Because airship  10  may utilize, for example, associated control surfaces, propulsion assemblies  31 , and its shape to remain suspended and substantially stationary over a given location, airship  10  may operate as a communications outpost in desired areas. Further, airship  10  may be employed for military or other reconnaissance/surveillance operations (e.g., for border patrol). 
     Operation of airship  10  may be performed by remotely controlling and/or utilizing manned flights of airship  10 . Alternatively, or additionally, airship  10  may be operated by preprogrammed automated controls, particularly for applications involving stationary flight. 
     In some embodiments, airship  10  may be configured to fly at altitudes of 30,000 feet or more. Capability of flying at such altitudes may facilitate various aforementioned operations, such as surveillance, communications, scientific studies, etc. In addition, high altitude flight such as this may enable airship  10  to take advantage of jet streams, and also fly above adverse weather conditions and/or turbulence that may otherwise be present at lower altitudes. In addition, flying at high altitudes, above clouds, may expose solar panel  1010  to more sunlight. Further, at higher altitudes, sunlight may be more intense, further enhancing collection of solar energy. 
     In some embodiments, airship  10  may be configured for use at extreme high altitudes, e.g. as a replacement for satellites. Such embodiments of airship  10  may be configured for stationary or mobile flight at altitudes of more than 60,000 feet. Certain embodiments may be capable of normal operation at altitudes of more than 100,000 feet. 
     In some contemplated applications, airship  10  may be flown using solar energy during daylight hours and batteries at night and/or while flying beneath cloud cover. During flight in which airship  10  may be flown completely using solar energy, airship  10  may store any excess solar energy collected by using it to charge batteries  1030 . 
     Certain embodiments of airship  10  disclosed herein may be equipped for water landing. Such embodiments may be applicable for landing in water of any depth. Therefore, airship  10  may be configured to land on a lake or ocean, airship  10  may also be configured to land on a swamp or other marshy site. Such airships may be used for applications at, or on, the water site. In addition, such airships may use the body of water/swamp as a landing site in an area that otherwise does not provide a landing place. For example, in order to travel to a heavily wooded area that does not provide a suitable landing site, an airship configured for water landing may land, for example, on a pond near the heavily wooded area. Airships equipped for water landing may be used, for example, to conduct research on a body of water, to perform construction, or to merely deliver materials and/or people to a location. 
     Some disclosed embodiments of airship  10  may include at least one deployable apparatus. As noted above, the deployable apparatus may be any of a number of different types of equipment. Airship  10  may be configured to implement the use of such equipment. 
     Whether configured for manned, un-manned, and/or automated flight, airship  10  may, according to some embodiments, be controlled by a computer  600 . For example, propulsion assemblies  31  and control surfaces, among other things, may be controlled by a computer  600 .  FIG. 30  is a block diagram of an exemplary embodiment of a computer  600  consistent with the present disclosure. For example, as shown in  FIG. 25 , computer  600  may include a processor  605 , a disk  610 , an input device  615 , a multi-function display (MFD)  620 , an optional external device  625 , and interface  630 . Computer  600  may include more or fewer components as desired. In this exemplary embodiment, processor  605  includes a CPU  635 , which is connected to a random access memory (RAM) unit  640 , a display memory unit  645 , a video interface controller (VIC) unit  650 , and an input/output (I/O) unit  655 . The processor may also include other components. 
     In this exemplary embodiment, disk  610 , input device  615 , MFD  620 , optional external device  625 , and interface  630  are connected to processor  605  via I/O unit  655 . Further, disk  610  may contain a portion of information that may be processed by processor  605  and displayed on MFD  620 . Input device  615  includes the mechanism by which a user and/or system associated with airship  10  may access computer  600 . Optional external device  625  may allow computer  600  to manipulate other devices via control signals. For example, a fly-by-wire or fly-by-light system may be included allowing control signals to be sent to optional external devices, including, for example, servo motors associated with propulsion unit mounts  430  and control surfaces associated with horizontal and vertical stabilizing member  310  and  315 . “Control signals,” as used herein, may mean any analog, digital, and/or signals in other formats configured to cause operation of an element related to control of airship  10  (e.g., a signal configured to cause operation of one or more control surfaces associated with airship  10 ). “Fly-by-wire,” as used herein, means a control system wherein control signals may be passed in electronic form over an electrically conductive material (e.g., copper wire). Such a system may include a computer  600  between the operator controls and the final control actuator or surface, which may modify the inputs of the operator in accordance with predefined software programs. “Fly-by-light,” as used herein, means a control system where control signals are transmitted similarly to fly-by-wire (i.e., including a computer  600 ), but wherein the control signals may transmitted via light over a light conducting material (e.g., fiber optics). 
     According to some embodiments, interface  630  may allow computer  600  to send and/or receive information other than by input device  615 . For example, computer  600  may receive signals indicative of control information from flight controls  720 , a remote control, and/or any other suitable device. Computer  600  may then process such commands and transmit appropriate control signals accordingly to various systems associated with airship  10  (e.g., propulsion system  30 , vertical and horizontal control surfaces  350  and  360 , etc.). Computer  600  may also receive weather and/or ambient condition information from sensors associated with airship  10  (e.g., altimeters, navigation radios, pitot tubes, etc.) and utilize such information for generating control signals associated with operating airship  10  (e.g., signals related to trim, yaw, and/or other adjustments). 
     According to some embodiments, computer  600  may include software and/or systems enabling other functionality. For example, computer  600  may include software allowing for automatic pilot control of airship  10 . Automatic pilot control may include any functions configured to automatically maintain a preset course and/or perform other navigation functions independent of an operator of airship  10  (e.g., stabilizing airship  10 , preventing undesirable maneuvers, automatic landing, etc.). For example, computer  600  may receive information from an operator of airship  10  including a flight plan and/or destination information. Computer  600  may use such information in conjunction with autopilot software for determining appropriate commands to propulsion units and control surfaces for purposes of navigating airship  10  according to the information provided. Other components or devices may also be attached to processor  605  via I/O unit  655 . According to some embodiments, no computer may be used, or other computers may be used for redundancy. These configurations are merely exemplary, and other implementations will fall within the scope of the present disclosure. 
     According to some embodiments, it may be desirable for computer  600  to transmit in-flight signals configured to, for example, correct course heading and/or assist in stabilizing airship  10  independent of an operator of airship  10 . For example, computer  600  may calculate, based on inputs from various sensors (e.g., altimeter, pitot tubes, anemometers, etc.), a wind speed and direction associated with ambient conditions surrounding airship  10 . Based on such information, computer  600  may determine a set of operational parameters that may maintain stability of airship  10 . Such parameters may include, for example, propulsion unit parameters, control surface parameters, ballast parameters, etc. Computer  600  may then transmit commands consistent with such parameters assisting in maintaining stability and/or control of airship  10 . For example, computer  600  may determine that as airship  10  gains altitude, the ballonet should be pressurized to prevent over-pressurization of first envelope  282 . In such a situation, computer  600  may cause air pumps to activate, thereby pressurizing the ballonet to a desirable pressure. It should be noted that data associated with wind and other various effects on airship  10  (e.g., aerodynamic stresses) may be determined empirically and/or experimentally, and stored within computer  600 . This may allow computer  600  to perform various actions consistent with safely navigating airship  10 . 
     As noted above, according to some embodiments, once aloft, it may be desired to hold airship  10  substantially stationary over a desired area and at a desired altitude. For example, computer  600  and/or an operator may transmit control signals to propulsion system  30 , vertical and horizontal control surfaces  350  and  360 , the ballonet, and/or other systems associated with airship  10 , such that airship  10  remains substantially stationary even where wind currents may cause airship  10  to be exposed to aerodynamic forces. 
     Although, for purposes of this disclosure, certain disclosed features are shown in some figures but not in others, it is contemplated that, to the extent possible, the various features disclosed herein may be implemented by each of the disclosed, exemplary embodiments. Accordingly, differing features disclosed herein are not to be interpreted as being mutually exclusive to different embodiments unless explicitly specified herein or such mutual exclusivity is readily understood, by one of ordinary skill in the art, to be inherent in view of the nature of the given features. 
     While the presently disclosed device and method have been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the disclosure. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process step, or steps to the objective, spirit, and scope of the present invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only.