Abstract: A drive unit for air vehicle, which allows building the vertical take-off and landing vehicles, intended for use, for instance, in the production of flying taxis, as well as in the model-making branch and in the toy industry. The drive unit is composed of the air channel, in the form of a straight segment of a tube with circular section, which has fans with engines fixed on its both ends. The vertical draft force outlet-inlet nozzle opening is located between fixed fans of the drive unit.

Abstract: An aircraft wing with a system for optimizing boundary layer control. The aircraft wing includes an enclosing structure, an inner cavity defined within the aircraft wing, and at least one bellows assembly disposed in the inner cavity. The bellows assembly is spaced apart from the inner surfaces of the enclosing structure so as to define a void between the bellows assembly and the inner surfaces. Boundary control inlets are defined in the enclosing structure and a wake-immersed propulsion exhaust duct disposed proximate the trailing edge of the wing.

Abstract: An aircraft includes: a plurality of rotor units each including a propeller and a motor that drives the propeller; and a shock absorber covering the entire vertical length of lateral sides of the plurality of rotor units.

Abstract: The disclosed unmanned aerial vehicle (UAV) includes a buoyant airbag, a drive unit, a retention feature, and an onboard control module that can be configured to cause the drive unit to displace the UAV, cause the retention feature to retain one or more items for transport, and receive instructions to transfer items from one location to another. For example, a UAV can be controlled to obtain an item at one location in a warehouse such as a first floor, lift said item to a second location in the warehouse such as a second floor, and deposit the item at the second location.

Abstract: An intelligence, surveillance, and reconnaissance system is disclosed including a ground station and one or more aerial vehicles. The aerial vehicles are autonomous systems capable of communicating intelligence data to the ground station and be used as part of a missile delivery package. A plurality of aerial vehicles can be configured to cast a wide net of reconnaissance over a large area on the ground including smaller overlapping reconnaissance areas provided by each of the plurality of the aerial vehicles.

Abstract: A buoyant aerial vehicle includes a buoyant vehicle body in which gas having a specific gravity smaller than air is hermetically filled, a vertical propulsion propeller which provides vertical propulsive force, and a horizontal propulsion propeller which provides horizontal propulsive force The buoyant vehicle body is configured with flotation chambers and connecting portions. The flotation chambers are arranged at positions point-symmetric with respect to a center of the buoyant vehicle body. Central portions of the flotation chambers are bulged in a side view and the connecting portions connect the flotation chambers. The connecting portions are formed in a flat shape thinner than the central portions of the flotation chambers such that wind passages along which the air flows are formed on the connecting portions, and the wind passages are oriented in at least two directions in the plan view.

Abstract: The herein invention is presenting a lift generating method based on a semi-open fluid jet flowing in a closed circuit around a lifting airfoil. A VTOL aircraft with maximized pay load room and car-like shape is the preferred embodiment of the invention. The herein aircraft uses no wings, exposed propellers, hot gas jets or other high injury risk means for propulsion and lift, and it can be driven by ordinary skilled people. Furthermore the aircraft has a small footprint and can land, take off and even cruise on water in one of the preferred embodiments.

Abstract: A solar-powered airship with a hull configured to contain a gas and at least one propulsion assembly with a propulsion device and electric motors configured to drive the propulsion device. The airship may also include a power supply system including solar panels operatively coupled to the electric motors and configured to supply power to the electric motors. The power supply system may also include batteries operatively coupled to the solar panels and configured to receive and store electrical energy supplied by the solar panels, the batteries being further operatively coupled to the electric motors and configured to supply power to the electric motors. The batteries may each be located within an outer envelope of the airship defined by the hull of the airship in a position selected to provide ballast. The solar-powered airship may also include a cargo system configured to contain passengers or freight.

Abstract: A lighter than air emergency beacon platform as part of a hydrogen generation and filtration apparatus includes at least one power source having at least one activation switch. At least one reaction chamber is electrically connected to the at least one reaction chamber by at least one low-resistance electrical conductor. The reaction chamber is configured to house a hydrogen generating material. At least one flow disruption chamber is in fluid communication with the reaction chamber. The flow disruption chamber(s) are configured to provide fluid communication with the next flow disruption chamber in the direction of fluid flow. At least one inflatable housing is configured to carry payload and is in fluid communication with the flow disruption chambers. The inflatable housing is detached from a fill tube to lift the payload above terrain blocking line-of-sight signal communication.

Abstract: A system for lifting gas replenishment in a tethered airship system includes an upper airship with a first end of a tether attached to the upper airship. A balloon is configured to travel up the tether toward the upper airship carrying a payload of lifting gas. A method for gas replenishment of an airship is also provided.

Abstract: An illustrative airship system for long endurance stratospheric operations includes an upper airship and a first end of a tether attached to the upper airship. A lower airship is attached to a second end of the tether and a payload airship is reversibly mated to the lower airship. The airship system is free flying and configured to maintain long duration station keeping. Illustrative methods for long endurance stratospheric operations are also provided.

Abstract: Embodiments according to the methods and systems provide for the selection, assembly, deployment, exploitation of data collected, redeployment, retrieval and stowage of a remotely operated lighter than air (LTA) network of vehicles. From modular components stowed with a mobile platform, one or more LTA vehicles can be assembled, deployed and retrieved. Determining the desirable number of LTA vehicles and the modular components to be assembled for each vehicle can be performed through a computer recommending modular components based on mission parameters. A remote controller device can be used for pre-deployment setup, in-flight mission management and analysis of data gathered by a plurality of possible sensing devise operably attached to the one or more LTA vehicles.

Abstract: The invention pertains to aeronautical engineering and consists of an airborne platform that can be built to large sizes without requiring a rigid structure of comparable dimensions and which uses both buoyancy and the aerodynamic Magnus effect for lift. The aerodynamic lift is generated in lifting bodies (1), which also contain buoyant gas. The lifting bodies (1) are stacked in a column, at the bottom of which there is a structural anchoring module (2) which also contains buoyant gas. The lifting bodies (1) and anchoring modules (2) are connected by slender structural elements which, when taken together as a whole form a non-rigid assembly. The platform may be tethered or configured as an aircraft, for which purpose other features may be added, such as a propulsion system (11), a crew gondola (6), cables to (7) and from (8) a swivel (12) and a payload (10) connected to said cables.

Abstract: Apparatus and method for a continuous replenishing of the lift gas and maintaining the proper pressure and lift of a tethered medium altitude aerostat utilizing a novel feed tube running the entire length of the tether. A first end of the feed tube is connected to the aerostat while a second end is connected through a novel slip ring means to a pressure controlled helium ballast chamber and scrubber on the ground to maintain pressure and lift by a reversible compressing pump. A plurality of pressure and temperature sensors and tension gauges strategically placed inside and around the airship continuously monitor the temperature and pressure changes in the aerostat. A data retrieval and communication unit mounted on the aerostat collects measurement data from the pressure, temperature and tension sensors which is relayed to the ground station and the data is used to regulate lifting gas pressure inside the aerostat.

Abstract: An airship may include a hull substantially shaped as an oblate spheroid, one or more frame members defining a support structure, wherein the support structure forms at least a partial support for the hull, at least one horizontal stabilizing member operably coupled to a lower surface of the airship, and at least one horizontal stabilizing member having a first end and a second end. The at least one horizontal stabilizing member may define an anhedral configuration. The airship may also include a vertical stabilizing member having a first end pivotally coupled to the airship and a second end oriented to remain below an upper surface of the airship. The vertical stabilizing member may be configured to pivot within a vertical plane, and the first end of the vertical stabilizing member and the first end of the at least one horizontal stabilizing member may be operably coupled to one another.

Abstract: Systems, method, devices and apparatus are provided for reducing drag and increasing the flight efficiency characteristics of aircraft and airships including hybrid aircraft utilizing distributed boundary layer control and propulsion devices. Boundary layer control includes passive systems such as riblet films and boundary layer propulsion devices having a divided and distributed propulsion system disposed in the curved aft sections of aircraft and airships including hybrid aircraft susceptible to boundary layer drag due to degree of curvatures, speed and density of the surrounding air. Distributed propulsion devices include constructing propellers and riblets from shape memory alloys, piezoelectric materials and electroactive polymer (EAP) materials to change the shape and length of the distributed propulsion device.

Abstract: The present invention is generally directed to tapes or laminates designed for use in conjunction with lighter-than-air vehicles, platforms or other inflated structures. In one embodiment, the present invention is directed to tapes or laminates designed for use in logos and/or identification numbers that can be, for example, used on a lighter-than-air vehicle, platform or other inflated structure. In another embodiment, the present invention is directed to tapes or laminates that include, among other layers, at least one dichroic layer designed to produce a logo, letter and/or number that can be, for example, used on a lighter-than-air vehicle, platform or other inflated.

Abstract: A hybrid lift air vehicle for lifting and transporting a payload to a delivery location, which comprises a helium or other lighter-than-air gas filled envelope mounted on an airframe.

Abstract: The present invention is generally directed to tapes designed for use in conjunction with lighter-than-air vehicles, platforms or other inflated structures. In one embodiment, the present invention is directed to conductive seam cover tape that can be, for example, used to protect and/or cover one or more seams in a lighter-than-air vehicle, platform or other inflated structure. In another embodiment, the present invention is directed to a conductive seam cover tape that can be, for example, used to protect and/or cover fabric panels or sections that are used to form lighter-than-air vehicles, platforms or other inflated structures that are in, one instance, designed for deployment at high altitudes.

Abstract: An airship may include a hull substantially shaped as an oblate spheroid, one or more frame members defining a support structure, wherein the support structure forms at least a partial support for the hull, at least one horizontal stabilizing member operably coupled to a lower surface of the airship, and at least one horizontal stabilizing member having a first end and a second end. The at least one horizontal stabilizing member may define an anhedral configuration. The airship may also include a vertical stabilizing member having a first end pivotally coupled to the airship and a second end oriented to remain below an upper surface of the airship. The vertical stabilizing member may be configured to pivot within a vertical plane, and the first end of the vertical stabilizing member and the first end of the at least one horizontal stabilizing member may be operably coupled to one another.

Abstract: Apparatus and method for a continuous replenishing of the lift gas and maintaining the proper pressure and lift of a tethered medium altitude aerostat utilizing a novel feed tube running the entire length of the tether. A first end of the feed tube is connected to the aerostat while a second end is connected through a novel slip ring means to a pressure controlled helium ballast chamber and scrubber on the ground to maintain pressure and lift by a reversible compressing pump. A plurality of pressure and temperature sensors and tension gauges strategically placed inside and around the airship continuously monitor the temperature and pressure changes in the aerostat. A data retrieval and communication unit mounted on the aerostat collects measurement data from the pressure, temperature and tension sensors which is relayed to the ground station and the data is used to regulate lifting gas pressure inside the aerostat.

Abstract: A system allowing for the controlled propulsion of aircraft, especially buoyant and semi-buoyant airships designed as a symmetric body of revolution, without the need for or use of aerodynamic control surfaces, comprised of a plurality of ducted fan thrusters placed both fore and aft, designed to ingest air flowing at less than free stream velocity. Fans are arranged such that when at standard orientation, the thrust from each is directed tangentially to an arc drawn along the hull from bow to stem. By defining multiple sets of thrusters based upon their location, differential thrust may be applied based upon set membership in order to affect translational and rotational maneuvering of the aircraft.

Abstract: An energy generating device for lighter-than-air vehicles having a gas impervious outer flexible fabric including a flexible photovoltaic array located on the outer layer of the gas impervious fabric; a thermocouple array located between the photovoltaic cells and the gas impervious fabric; a thermally conductive layer or heat spreader between the thermocouple array and the photovoltaic array and between the thermocouple array and the gas impervious flexible fabric; an electrically conductive means connected to said thermocouple array for drawing electrical power away from said thermocouple array; and an electrical load, such as an electrical storage device or a device that consumes electricity, for drawing electricity from the thermocouple array.

Abstract: A hybrid lift air vehicle for lifting and transporting a payload to a delivery location, which comprises a helium or other lighter-than-air gas filled envelope mounted on an airframe.

Abstract: An airship comprises a shell, a gas storage system, an air storage system, a cargo storage system, a heating system, and a propulsion system. The shell encompasses a volume. The gas storage system is located within the volume, wherein the gas storage system is capable of storing a lighter than air gas. The air storage system is located within the volume, wherein the air storage system is capable of storing heated air. The heating system is capable of heating air. The propulsion system is capable of propelling the shell during flight.

Abstract: A dehumidification system for removing water vapor from the within the envelope of an airship comprises a pressurizer valve, a blower and a dehumidifier attached to the airship. The pressurizer valve releases air from the envelope and directs the air to the blower. The blower forces the air through the dehumidifier where the air is dried to a desired dew point. The dried air is then forced back into the envelope of the airship, thus reducing the weight of the airship and reducing the amount of condensate that may form during an ascent.

Abstract: A laminate material for lighter-than-air vehicles includes a liquid crystal polymer fiber layer, a polyimide layer secured to the liquid crystal polymer fiber layer; and a polyvinylidene fluoride (PVDF) layer secured to the polyimide layer. The layers are secured to one another with a polyurethane adhesive. Adjacent laminates may be secured to one another by a PVDF cover tape on the exterior surfaces and a structural tape on the interior surfaces. The structural tape includes a liquid crystal polymer fiber layer and a polyimide layer to ensure the integrity of the vehicle. An alternative material may include a liquid crystal polymer fiber layer and a polyvinylidene fluoride (PVDF) layer disposed on both sides of the liquid crystal polymer fiber layer.

Abstract: The present invention provides a solar-powered transformable airship, on which solar cell panels are installed all over to maximize the amount of solar energy collected. Moreover, the airship according to the present invention has a main body of variable volume, suitable for any altitude, ranging from the ground to 30 kilometers high, providing very good economic potential.

Abstract: In one aspect, a hybrid airship including an outer shell, a plurality of helium filled gas envelopes, and an all-electric propulsion system can have a high-aspect ratio wing shape. In some embodiments, the hybrid airship may be launched using buoyancy lift alone and aerodynamic lift may be provided by the all-electric propulsion system. In one aspect, a photovoltaic array and a high energy density power storage system may be combined to power the propulsion system making the propulsion system regenerative. The high-aspect ratio wing shape provides low drag, and can allow the hybrid airship to fly at an altitude of at least about 100,000 ft. By continuously recharging the power storage system, the hybrid airship in accordance with some embodiments can stay aloft for months or even years. The hybrid airship may function as a military intelligence, surveillance, and reconnaissance and communications relay platform.

Abstract: The invention concerns a lighter-than-air craft for transporting by air equipment and passengers, more particularly, it concerns an aircraft whereof the frame (1) made of light metal and erected vertically, contains and protects the passenger compartment (4) of the invention, and all the components of the invention which, by a mass-reducing assembly (2-8-9-11-19), uses light gas power for neutralizing the earth's gravitational pull. Electric motors actuating propellers (6-7) with multiple blades and powered by a mini-electric power unit (5) enable to counter the force of mean winds, so to lift the neutralized mass and control the aircraft movements. The aircraft wide external surfaces (11-12) are used as wing system, a sailboat keel being replaced by a gyroscope (10) stabilizing effect and by the thrust of the lateral propellers (6).

Abstract: An aircraft is provided having an inflatable parafoil canopy wing and a suspended fuselage. The wing is constructed such that, when inflated, it has an airfoil configuration having leading and trailing edges, thereby producing lift by interaction with air encountered by the leading edge. A central compartment confines a buoyant gas which causes the total volume of the wing to be varied in response to the degree of inflation with the buoyant gas. With sufficient inflation, the aircraft is capable of vertical take-off and landing (VTOL).

Abstract: A balloon comprising an envelope, wherein the envelope has a multilayered structure comprising a gas-impervious sheet, and a liquid absorbent sheet overlaid on the inner surface of the gas-impervious sheet.

Abstract: A tie-down device secures an aircraft to the ground. The tie-down device includes a hook and slide member operating within the hook to secure a line. In use the line passes through an aperture within the slide member for biasing against a bottom portion of the hook when an opposing end of the line is placed under tension pulling against a top portion of the hook and is used to secure an aircraft to a ground anchor. A second embodiment includes an elongated slide member replacing the wheel. The slide member includes an aperture for receiving the line therethrough and a groove along a peripheral portion for sliding engagement with the hook. In addition, the slide member includes a release arm, accessible to a user, for pulling against the tension holding the line in frictional contact against the bottom portion of the hook.

Abstract: An aircraft includes an aircraft body that retains gas that is lighter than air and rotates about a vertical axis, and a cargo carrier attached to the body so that the carrier does not rotate with the body. The aircraft includes one or more propulsion devices that cause the aircraft body to rotate and to move laterally through air. The propulsion devices use gas retained in the aircraft body as fuel. One or more wings may extend from the body, which control the vertical motion of the aircraft during travel. A computerized navigation system is provided with the aircraft to permit the aircraft to be preprogrammed to travel a desired travel path, or to permit the aircraft to be remote controlled. The electronic components of the aircraft are powered by one or more power supplies, which may also act as ballast weights to raise the center of gravity of the aircraft as it spins, and to maintain tension on the aircraft body as fuel is consumed.

Abstract: An aircraft utilizes a buoyant evacuated rotating envelope to provide at least a portion of the lift required. The rotating envelope may be in the form of a disk, cylinder or other suitable shape. In one embodiment, an evacuated rotating envelope in the form of a disk is utilized. The disk is provided with a central core tube with at least one jet engine mounted therein. The deflection of the exhaust causes rotation of the envelope. A non-rotating payload compartment is mounted to the rotating envelope by bearings. Structures are provided for deflecting the exhaust to be utilized for lateral propulsion as well as for stabilizing the payload compartment to prevent rotation. Two other embodiments utilize rotating cylinders which may be rotated either by a jet engine mounted within a core tube or by an off center jet engine which drives the cylinder.

Abstract: The hybrid dirigible craft belongs to the category of flying vehicles which use an air cushion and take off and land at any type of airfield. The air of the invention is to design an improved dirigible craft capable of taking off from and landing on water and low-load bearing surfaces.

Abstract: A stable and highly maneuverable lighter-than-air aircraft is provided. The aircraft includes a body portion which is supported beneath a balloon portion by a stem or axle. The balloon is fillable with a lighter-than-air gas and is sized to accept sufficient amounts of gas to make the aircraft buoyant. The balloon portion is rotationally fixed to the axle and the axle is rotationally journaled in the body. Thus, the balloon portion can rotate relative to the body portion and the body can selectively be rotated relative to the axle. A motor is housed in the body portion and is operable to propel the aircraft in a desired direction. The aircraft is operated such that the balloon portion rotates above the body portion without rotating the body portion. The rotation of the balloon portion provides stability to the aircraft and the ability for the body portion to rotate about the axle enables the aircraft to be highly maneuverable.

Abstract: An airship capable of vertical and horizontal flight and able to make right angle turns is preferably of nearly neutral buoyancy and comprises two gas bags, the lower of which is toroidal in shape and surrounds a centrally located engine that has a downwardly facing inlet. Upwardly directed thrust from the engine is redirected by a gate valve arrangement into a manifold of ducts, each of which passes between the upper and lower gas bags to a respective outlet or nozzle adjacent the periphery of the aircraft. To fly the aircraft, a pilot uses the cable-operated valve arrangement to manage the distribution of thrust from the engine into selected ones of the ducts to provide thrust in a desired direction. Preferred pilot operated controls comprise a foot pedal and a rotatable steering wheel mounted on a pedestal hingedly attached to the gondola of the aircraft for fore and aft pivoting motion.

Abstract: An airship includes a gas envelope filled with a buoyant gas, a duct equipped with an internal propulsion fan and attached to the aft of the gas bag, a boom projecting aft along an extension of the axis of the propulsion fan and an empennage provided on the distal end of the boom and is constituted to prevent boundary layer separation by causing the propulsion fan to suck air flowing along the hull surface into the duct and jet it aft.

Abstract: An airship in the form of a self-powered, elongated dirigible which comprises at least three sections connected together by joints. The sections including a front section with propulsion devices and control surfaces, at least one intermediate section designed to carry a payload and a rear section with control surfaces. The joints allow limited articulation between sections under gust conditions and tend to return the sections to aligned condition in calm air. A cover may provide a streamline exterior shape for the airship; alternatively the sections may have rims which mate together when there is no articulation to provide a smooth exterior shape.

Abstract: An airship in the form of a self-powered, elongated dirigible which comprises at least three sections connected together by joints. The sections including a front section with propulsion devices and control surfaces, at least one intermediate section designed to carry a payload and a rear section with control surfaces. The joints allow limited articulation between sections under gust conditions and tend to return the sections to aligned condition in calm air. A cover may provide a streamline exterior shape for the airship; alternatively the sections may have rims which mate together when there is no articulation to provide a smooth exterior shape.

Abstract: A tethered surveillance balloon having a relatively low lift-to-weight ratio (e.g., 1.1) and an aerodynamic device to help maintain the surveillance balloon elevation when subject to high velocity wind conditions at an altitude which is a high percentage of the altitude the surveillance balloon would assume if there was zero wind velocity and all other conditions were the same (e.g. temperature, air density). The surveillance balloon also includes a sensing device such as a TV detector for detecting objects and relaying information to a ground station and with possibly a target designation device, if so desired. The balloon is formed of a material which is virtually, if not entirely, radar and visibly transparent.

Abstract: An airship having improved controllability which comprises: an axial fluid pathway penetrating through a body of the airship in an axial direction, at least one radial fluid pathway crossing the axial fluid pathway and penetrating through the body in a radial direction, the axial fluid pathway and the radial fluid pathway forming a ventilating-thrusting tube having a rigid framework construction, propulsion means, thrust generating direction of which is adjustable, arranged in a crossing region of the axial fluid pathway and the radial fluid pathway, and a lift balloon arranged beside the ventilating-thrusting tube in such a manner that a gap is formed between the ventilating-thrusting tube and the lift balloon to allow air to flow through. This arrangement lowers a tendency of yawing due to a transverse wind. The airship has a semi-rigid and semi-flexible construction capable of making up for drawbacks of both rigid type and flexible type.

Abstract: A rigid airship is disclosed herein having an annular or toroidal airfoil fuselage in front elevation for housing several elongated gas cells containing a buoyant gas such as helium. The fuselage includes at least two longitudinal and a plurality of transverse structural members for supporting the cells. A covering is provided about the fuselage comprising a multiplicity of fitted panels joined by retainer straps and locking nodes. The fuselage defines a central venturi having an annular intake and a contracted exit through which an elongated tapered tail cone extends in coaxial relationship with the fuselage. Boundary layer control is effected via manifolds associated with the fuselage panels and a variable geometry venturi passageway is effected by longitudinal movement of a control compartment and adjoining tapered tail cone.

Abstract: A flying machine (L.T.A.-H.T.A. Hybrid) connected through the fuselage . . . using a two-point-lift system wherein the lifts are static and dynamic . . . separately and simultaneously. The static lift is supplied by an aerostat (#36) while the dynamic lift is supplied by an atmospheric deflector (#48) . . . This system, by the clever use of 180 degrees pivotable pusher (blower) engine (#1), being and becoming capable of:1. S. T. O. L. and/or V.T.O.L.2. Rearward FlightA two-point-lift system, as stated in the preferred embodiment (technical description), employing L. T. A. and H. T. A. method (separately and simultaneously) to be allowed development on a non-exclusive basis (excluding Balopod). The process levels the device by coordinating static lift, thrust, and dynamic lift.

Abstract: An air vehicle for lifting loads generates lift forces from helium gas within a torus-shaped envelope having a central passageway, and from a fan arrangement designed to direct air downwardly through the passageway. Lateral propulsion units are provided on the envelope. In one embodiment, the fan arrangement comprises two fans carried by a saddle supported on the envelope, while in another embodiment a single fan is carried by a gondola suspended from the envelope.

Abstract: A hybrid annular airship of the kind including an annulus containing at least one gas containing portion is disclosed which is characterized by improved maneuverability, stability and speed. This improvement is effected by combined means comprising a pair of tubes mounted diametrically within the annulus and normal one to the other. A plurality of doors are provided for selectively closing off one or the other of the pair of tubes. Each tube is provided with a propulsion unit, having an access port, and preferably reversibly mounted therein. The tubes either are mounted on the same level or at different levels. Preferably, the propulsion units are jet engines which are individually operable. An elevator and a walkway preferably are provided communicating with each of the access ports leading to the propulsion units. Preferably, each access port has its own opening and closing mechanism.

Abstract: The use of thrusters at the bow and stern of an airship for control of the direction, attitude, and orientation of such an airship is described. The thruster utilizes an electric motor or a gas turbine for power. In the electric motor embodiment, the motor utilizes two contra-rotating rotors which each drive a separate and contra-rotating propeller to generate the controlling jet of air. Thrusters are arranged in pairs at the top, bottom, and each side of the bow and stern of the airship. Lifting thrusters directed downwardly and located above the longitudinal extent of the hull are provided to augment the static lift capability of the airship when under heavy load.