HIGH-ALTITUDE AEROSTAT WITH A LARGE SURFACE AREA

Abstract

A variable-volume aerostat, consisting of a flat gas envelope, joined to guide aerostat bodies. The flat gas envelope is typically deployed by rotation of cylindrical guide airships, or rollers suspended beneath guide aerostats. In its stowed configuration, the flat gas envelope is rolled, uninflated and relatively compact. As the invention ascends to high altitude, lifting gas expands out of the guide aerostats into the unrolling flat gas envelope. When fully deployed, the flat gas envelope is self-supporting, and has a horizontal surface area up-to 100 times larger than that of the guide aerostats. This is a major advantage in potential applications, including targeted Solar Radiation Management (SRM), and airborne solar power generation.

Claims

1. A variable volume aerostat which can expand its surface area, comprising: one or more strips of flat gas envelope, made of a lightweight material which is impervious to the lifting gas; depth-constraining structures which constrain the depth of the flat gas envelope; aerostat bodies, in the form of airships or balloons, joined to the flat gas envelope; opening or pipes which enable lifting gas to flow between the gas cells inside one or more of the aerostat bodies and the interior of the flat gas envelope; wherein in the stowed configuration, the flat gas envelope is uninflated, and the gas cells inside the aerostat bodies contain virtually all of the lifting gas; and wherein in the deployed configuration, lifting gas fills the flat gas envelope, which is fully extended and self supporting, and presents an area to the sun much larger than the area presented by the aerostat bodies.

2. A variable volume aerostat according to claim 1, further comprising strengthening of the flat gas envelope, which by way of example but not limitation can consist of strong lightweight fibres woven into the envelope material, or strong lightweight cables attached to the envelope at intervals.

3. A variable volume aerostat according to claim 1, further comprising lightweight pipes along the width of the flat gas envelope, wherein the flow of lifting gas between said flat gas envelope and the gas cells inside one or more of said aerostat bodies is expedited.

4. A variable volume aerostat according to claims 2 and 3 in which said pipes are made of a strong and lightweight material, and in which said pipes provide the necessary lateral strengthening of said flat gas envelope.

5. A variable volume aerostat according to claim 3 further comprising: division of said flat gas envelope into separate sections along its width; a series of active or passive valves in said pipes which control the flow of lifting gas between the internal envelope and individual sections of said flat gas envelope; wherein during ascent, lifting gas expanding from the internal envelope of one or more of said aerostat bodies, is directed into the section of said flat gas envelope that is being unrolled or unfolded; and wherein during descent, lifting gas is directed out of the section of said flat gas envelope that is being rolled or folded, into gas cells inside said aerostat bodies.

6. A variable volume aerostat according to claim 1, additionally comprising: A cylindrical structure at one or either end of said flat gas envelope, which is able to rotate on the longitudinal axis and act as a roller; non-rotating attachment points, joined to the ends of the longitudinal axis of said roller or rollers via rotating mounts; wherein the uninflated flat gas envelope can be rolled onto said roller or rollers before the invention ascends; wherein the flat gas envelope can be unrolled from said roller or rollers, and be inflated with lifting gas, as the invention ascends; wherein the deflating flat gas envelope can be rolled back onto said roller or rollers as the invention descends; and wherein any tethers, propulsion systems, supplemental buoyancy, or other non-rotating structures, can be attached to a roller at non-rotating external attachment points on the longitudinal axis.

7. A variable volume aerostat according to claims 6 and 2 wherein: said cables have a diamond shaped cross section of consistent size; said cables are integrated into the top and bottom surfaces of said flat gas envelope; said cables are offset by half their width from the bottom cables; said cables diverge by an amount equal to one full cable width for the each circumference of said roller; wherein in the rolled configuration, the lower inner facet of each subsequent layer of said cables rests upon the outer upper facet of the previous layer of said cables; and wherein said cables form a natural guide for the successful and compact rolling of said flat gas envelope.

8. A variable volume aerostat according to claims 6 and 3 wherein: said pipes have a diamond-shaped cross section of consistent size; said pipes are integrated into the top and bottom surfaces of said flat gas envelope; the top pipes are offset by half their width from the bottom pipes; said pipes diverge by an amount equal to one full cable or pipe width for the each circumference of said roller; wherein in the rolled configuration, the lower inner facet of each subsequent layer said pipes rests upon the outer upper facet of the previous layer of said pipes; and wherein said pipes form a natural guide for the successful and compact rolling of said flat gas envelope.

9. A variable volume aerostat according to claim 6, further comprising: matching holes in the opposing surfaces of said pipes; a sealing coating on the opposing surfaces of said pipes; and wherein the holes act as a passive valve, by being sealed to the movement of lifting gas when pressed together.

10. A variable volume aerostat according to claim 6, forming a rollable aerostat, wherein: said roller or rollers are also said aerostat bodies, being formed of a rotatable airship which has a main body in the approximate shape of a cylinder; in the stowed configuration, said flat gas envelope is uninflated, and rolled around the rotatable airship or airships; as the invention ascends, said flat gas envelope is unrolled by controlled rotation of the rotatable airship, and inflates with lifting gas expanding from the gas cells inside the rotatable airship; in the deployed configuration, said flat gas envelope is fully unrolled, and has been filled with sufficient lifting gas to make it neutrally buoyant; and as the invention descends, said flat gas envelope is rolled around the body of the rotable airship during controlled rotation, pushing the lifting gas back into gas cells inside the rotatable airship.

11. A rollable aerostat, according to claim 10, additionally comprising: an external rotator, suspended below said external attachment point; energy storage or other mass mounted on the external rotator at a significant distance from the longitudinal axis of said rotatable airship; motors, gears and control mechanisms attached to said rotating mount; and an onboard control system; wherein the off-axis weight of the external rotator provides a restoring torque; and wherein the off-axis buoyancy of any supplementary buoyancy provides a restoring torque; and wherein a torque applied through each rotating mount, rotates said rotatable airships.

12. A rollable aerostat, according to claim 10, further comprising: one or more internal rotators, suspended along the longitudinal axis in the interior of said rotatable airship, via a rotating mount; energy storage or other mass mounted on the internal rotator, at a significant distance from the longitudinal axis of a rotatable airship; motors, gears and control mechanisms attached to each rotating mount; wherein a torque applied through each rotating mount, rotates said rotatable airship, in reaction to the restoring torque provide by the off axis weight; and wherein the combined weight of the internal rotators and said external rotators, is more evenly distributed along the length of said rotatable airship; and wherein said rotatable airship can be rotated, without having to overcome deflection along its longitudinal axis, caused by uneven weight distribution.

13. A rollable aerostat according to claim 10, further comprising a rack-and-pinion rotator system consisting of: one or more ring rails, consisting of a rack rail and parallel guide rails, mounted around the inner or outer circumference of said rotatable airship; a railcar carrying a heavy counterweight, such as batteries, which can be driven along the rack rail by rotating pinions; a live rail or spark-safe electrical connection points, to enable the self-driving car to exchange electricity with the main electrical system; wherein the railcar applies a torque about the longitudinal axis of said rotatable airship, proportional to the sine of the angle between its position and vertical; and wherein the off-axis weight used to rotate said rotatable airship, is more evenly distributed along the length of said rotatable airship; and wherein said rotatable airship can be rotated without having to overcome deflection along its longitudinal axis, caused by uneven weight distribution.

14. A rollable aerostat according to claim 13, further comprising: longitudinal rack rails which intersect with said ring rails around circumference; rotating intersections between said ring rails and straight rails; wherein said railcars can be moved longitudinally between different ring rails; and wherein the centre of mass of said rotatable airship can be moved forwards or aft, for the purpose of controlling its pitch.

15. A variable volume aerostat according to claim 6, additionally comprising structures which suspend said rollers below said aerostat bodies; rotating joints, which by way of example but not limitation can consist of rotary unions, connecting said pipes from the aerostat bodies to said flat gas envelope, at the axis of said rollers motors and control systems for rotating said rollers; wherein the flat gas envelope can be unrolled or rolled by rotating said roller or rollers; and wherein lifting gas can move between the gas cells inside the aerostat bodies and the flat gas envelope.

16. A variable volume aerostat according to claim 1, additionally comprising a multi-directional propulsion system, including thrusters, energy storage and a control system, attached to said aerostat bodies, wherein: the relative position of said aerostat bodies can be accurately controlled; the invention can change its orientation, position and speed; and a lateral stretching force can be exerted along the width of said flat gas envelope, by using the multi-directional propulsion system to separate said aerostat bodies.

17. A variable volume aerostat according claim 1, additionally comprising one or more lightweight tethers attaching the invention to winches at the Earth's the surface, or mounted on a lower altitude vehicle, wherein the invention can ascend to high altitude whilst its geographic position is controlled by the force exerted through the tethers.

18. A variable volume aerostat according to claim 6, additionally comprising lightweight tethers attached to said non-rotating external attachment points, and to winches separated by more than the full width of said flat gas envelope, and motors and a control system which control the rotation of the roller, wherein: in the stowed configuration said tethers are withdrawn, most of said flat gas envelope is rolled, and rotational of the rollers is locked; during deployment, said tethers are steadily unwound, allowing the invention to ascend; as the invention ascends, the force exerted by the tethers is allowed to steadily rotate said rollers whilst maintaining some tension in said flat gas envelope, unrolling said flat gas envelope, which fills with lifting gas; and in the deployed configuration, the force exerted by the tethers continues to maintain the position of the invention and the tension in said flat gas envelope.

19. A variable volume aerostat according to claim 6, further comprising two drums at either end of each of said rollers, and pairs of tethers counter-wound around the two drums, wherein differential tension applied to the tethers can be used to rotate said rollers in order to unroll or roll said flat gas envelope.

20. A variable volume aerostat according to claim 1, further comprising designed points of folding, using by way of example but not limitation differential length or differential elasticity in said depth-constraining structures, wherein: said flat gas envelope has a naturally tendency to fold due to the differential buoyancy between the deepest and shallowest parts of the envelope; relaxation of the stretching tension applied at said aerostat bodies causes said flat gas envelope to fold; and the width and surface area of said envelope can be reduced during hours of darkness.

21. A variable volume aerostat according to claim 1, further comprising an additional central airship attached near the middle of said flat gas envelope, wherein: additional weight near the middle of said flat gas envelope can be supported by the buoyancy of the central airship; the central airship can be used an attachment point for tethers or cables connecting the invention to the ground or a lower altitude craft; and if of a non-rigid type, the central airship can act as a physical buffer between two of said aerostat bodies at the ends of said flat gas envelope.

22. A variable volume aerostat according to claim 21, further comprising a system of variable buoyancy in said central airship, such as ballonets (PTL5), wherein a change in the buoyancy of said central airship can be used to help put said flat gas envelope into a v shape, wherein the radiatively-active surface area is significantly reduced.

23. A variable volume aerostat according to claim 1, wherein said flat gas envelope has a top layer or coating of high albedo, wherein a high proportion of incident solar radiation is reflected back into space, wherein during hours of daylight, there is a net cooling the area on the Earth's surface that is shadowed by the invention.

24. A variable volume aerostat according to claim 1, wherein in the deployed configuration, said flat gas envelope can be disconnected from said aerostat bodies, to float freely in the atmosphere.

25. A variable volume aerostat for solar power generation according to claim 1, additional comprising: a layer of ultrathin photovoltaic film on the top surface of said flat gas envelope; connecting conductors; electricity control systems; and electricity storage and/or transmission systems; wherein during the hours of daylight, large amounts of incident solar radiation is converted into electricity.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0084] The diagrams illustrate the basic components of the invention at launch, during ascent, or at the target working altitude. None of the diagrams are to scale. In particular, the relative width of the flat gas envelope is much less than in a real system.

[0085] FIG. 1a shows a simplified plan view from above the Rollable Aerostat in its stowed configuration, showing the connected airships (104) with their cylindrical main body obscured by the uninflated flat gas envelope (102) wrapped around them.

[0086] FIG. 1b shows a simplified front section view of the Rollable Aerostat in its stowed configuration, showing the circular cross-section of the connected airships (104), and the uninflated flat gas envelope (102) wrapped around each cylindrical main body.

[0087] FIG. 2a shows a simplified plan view from above the Rollable Aerostat in its deployed configuration, showing the distanced airships (104), and the inflated and neutrally-buoyant flat gas envelope (102) extended between them.

[0088] FIG. 2b shows a simplified front section of the Rollable Aerostat in its deployed configuration, showing the circular cross-section of the distanced airships (104), and the inflated and neutrally-buoyant flat gas envelope (102) extended between them.

[0089] FIG. 2c shows a simplified section across the flat gas envelope in its deployed configuration, showing the depth constraining structures (101) and the cables (115).

[0090] FIG. 2d shows a detailed view from above the flat gas envelope in its deployed configuration, showing the depth constraining structures (101) and the cables (115).

[0091] FIG. 3a is a cross-section view through one connected airship (104) in a Rollable Aerostat, showing the internal rotator, including the rotating mount (108), suspension frame (109), counterweight (110) and neutrally-buoyant flat gas envelope (102).

[0092] FIG. 3b is a detailed view of the rotating mount, illustrating electric motors (105) turning a large gear (107) attached to the central spine (106) of the airship.

[0093] FIG. 4a is a front-elevation view of an airship (104) in an end-tethered Rollable Aerostat. The hemi-ellipsoidal end-cap is illustrated by concentric circles. It shows the external rotator including the rotating mount (108), suspension frame (109), and counterweight (110), and a ground tether (111) attached to the counterweight.

[0094] FIG. 4b is a front-elevation view of a connected airship (104) in an autonomous Rollable Aerostat, showing a multi-directional propulsion system, including tiltable thrusters (114), power storage (112), and a powered swivel (113) joining it to the suspension frame (109).

[0095] FIG. 5 shows a view of the rack rotator mechanism inside the surface of an airship (123), consisting of the circular rack (118), guide-rail (119), and railcar (117).

[0096] FIG. 6 shows a cross-section through an unrolling flat gas envelope including diamond cross-section pipes with perforated internal facets. In rolled segments of the envelope (121) the stacked pipes (122) sit on top of a fixed pipe-shape (125) attached to the surface of the airship (123). The internal facets of the stacked pipes (122) form a seal against each other. In the unrolling segment of the envelope (120), the exposed perforations in the internal facets of the parted pipes (126), enable lifting gas to flow from the gas cells inside the airship (124) into that segment of the envelope.

[0097] FIG. 7 is a simplified front section view of a Rollable Aerostat, featuring an additional central isolated aerostat body, in its stowed configuration. It shows the uninflated flat gas envelope (102) wrapped around each connected aerostat (104), and a partially-inflated semi-rigid isolated aerostat (127), which supports the weight of solar cells (103) in the middle of the flat gas envelope.

[0098] FIG. 8 shows a close-up front section of one Suspended Roller in its stowed configuration. A cylindrical roller (131) is suspended below a connected aerostat (136), with the uninflated flat gas envelope (102) rolled around it. Pipes (116) connect the interior volume of the connected aerostat to the flat gas envelope via a rotary union (135) on the axis of the roller. Motors (134) rotate the roller to unroll or roll the flat gas envelope.

[0099] FIG. 9 shows a front section view of the Suspended Roller embodiment in its stowed configuration. Two end bodies (136) each include one or more aerostats. The flat gas envelope (102) is wrapped around cylindrical rollers (131) suspended below the end bodies.

[0100] FIG. 10 is a side view of the Suspended Roller embodiment, showing one of two ellipsoid airships (132) with three rollers (130) suspended below its keel (133).

[0101] FIG. 11 Is an illustrative cross-section of the summer hemisphere showing approximate positions of the tropopause (140), polar jet or jet stream (141) and tropical jet (142). The dotted box (143) indicates the most accessible part of the lower stratosphere.

[0102] FIG. 12a illustrates a dual connection layout with two connected aerostat end-bodies (150).

[0103] FIG. 12b illustrates a mono connection layout with one connected aerostat end-body (150) and one isolated end-body (151).

[0104] FIG. 12c illustrates a triple connection layout of two connected aerostat end-bodies (150), and one central connected aerostat body (150).

[0105] FIG. 12d illustrates a central connection layout with one connected aerostat end-body (150) and two isolated end-bodies (151).

[0106] FIG. 12e illustrates a dual connection layout with two connected aerostat end-bodies (150), and a central isolated aerostat body (151).

DESCRIPTION OF EMBODIMENTS

[0107] All the embodiments can be used in either an autonomous or tethered solution, may feature supplementary buoyancy, and may be applied to SRM, solar power generation, or other high-surface-area applications.

[0108] All the embodiments can be formed in a range of different layouts of internally-connected and isolated aerostats, which by way of example but not limitation include the mono-connection; dual-connection; triple connection, or central-connection layouts illustrated in FIGS. 12a to 12e.

[0109] In the simplest embodiment, the flat envelope is not rolled on or under the connected aerostats. It may be folded at take-off and then released, or released at take-off in an open state. In smaller examples of the simplest embodiment, the isolated aerostats (151) can be left out of the layouts shown in FIGS. 12a to 12e. In this case, gas pressure alone shapes the flat envelope.

[0110] The preferred embodiment, the Rollable Aerostat, is illustrated in FIGS. 1-4 in the dual-connected layout. In this embodiment the aerostat bodies are airships with a cylindrical main body (104). The cylindrical section of each internally-connected airship acts as a roller for stowing the uninflated flat gas envelope (102) at ground level, and deploying and retracting the flat gas envelope as the invention ascends and descends.

[0111] An alternative embodiment, the Suspended Roller, is illustrated in FIGS. 7 to 9 in the dual-connected layout. The Suspended Roller embodiment enables multi-purpose airships (132,136) of pre-existing designs, to deploy a relatively large surface. One or both ends of the flat gas envelope (102) are wound around a cylindrical roller (131), suspended below one or more aerostats.

[0112] In the Suspended Roller embodiment, the interiors of the aerostat envelopes and flat gas envelope are joined by gas pipes (116), connected via a rotary union (135) on the axis of the cylindrical roller. Motors (134) rotate the cylindrical roller to unroll and roll the flat gas envelope. By way of example but not limitation, the cylindrical rollers may be suspended below balloons (FIG. 9), ellipsoid airships (FIG. 10) or two balloon airships (PTL4).

[0113] Unlike the Rollable Aerostat, the roller (131) in the Suspended Roller does not support its own weight. The maximum length of a Suspended Roller is limited by its bending stiffness, because significant deflection along its length inhibits rotation.

[0114] FIG. 10 shows multiple Suspended Rollers suspended from the keel of a semi-rigid ellipsoid airship (132). Opposing pairs of suspended rollers (130) deploy parallel strips of flat gas envelope (102). The use of multiple in-line rollers enables the solution to scale to large airship designs, and enables modular designs.

[0115] The typical disadvantages of the suspended roller embodiment over the Rollable Aerostat embodiment are lower maximum altitude, reduced area of flat gas envelope, and reduced ability to orientate the surface of the flat gas envelope sunwards.

EXAMPLES

[0116] The airship-based examples in this section illustrate a range of possible applications, which are not intended to be exhaustive.

[0117] As illustrated in FIG. 11, the minimum altitude required to access the lower stratosphere varies between approximately 10 km near the poles to up to 20 km in the tropics. Short duration systems can be operated at lower altitudes with suitably active management.

[0118] In the summer polar stratosphere, zonal winds are relatively low (NPL2), and the sun is in the sky for a high proportion of the day, albeit at a low solar altitude angle. This comprises the most practical working environment for medium to long duration applications.

[0119] The following information and assumptions are used in estimating the dimensions and properties of the examples in this section: [0120] The deadweight of an airship is approximately proportional to its surface area. [0121] The deadweight of rigid airships constructed with modern materials can be 50% lower than historic designs. [0122] The gas envelopes of an airship can occupy 90% of its internal volume. [0123] High albedo surfaces or coatings of areal densities less than 200 g/m.sup.2 are available. [0124] Ultrathin photovoltaic films, optimised for the solar spectrum at high altitudes, are available at areal densities less than 200 g/m.sup.2 (NPL5). [0125] The mean areal density of the flat gas envelope can be 500 g/m.sup.2, based on [0126] two surfaces of flat gas envelope of 100 g/m.sup.2 (NPL4) [0127] reinforced with carbon fibre yarns [0128] connected by carbon fibre tendons [0129] a radiatively-active layer of 250 g/m.sup.2 [0130] The examples all use the dual-connection layout shown in FIG. 12a [0131] Weight of ground tethers and any high-tension electrical cables, can be supported by supplementary buoyancy.

[0132] Table 1 sets out approximate values for the key properties of various example classes (A to F) of rollable aerostats and suspended rollers, based on the above information and assumptions, and using the equation (1) and equation (2) above.

TABLE-US-00001 TABLE 1 Example Classes of Rollable Aerostat and Suspended Roller Systems Aerostat Bodies (each) Flat Envelope Area Target Dead Full Surface Expansion Class Embodiment Altitude Description Length Radius* weight Length Width Area Ratio A Rollable 8 km Rigid cylindrical airship 75 m 7.5 m 3.4 t 60 m 700 m 42,000 m.sup.2 20 Aerostat B Rollable 16 km Rigid cylindrical airship 240 m 20 m 30 t 200 5 km 1 km.sup.2 60 Aerostat C Rollable 20 km Semi-rigid cylindrical 140 m 20 m 10 t 100 m 6.5 km 650,000 m.sup.2 60 Aerostat airship with internal bracing D Rollable 22 km Rigid inflatable frame 264 m 32 m 36 t 200 m 15 km 3 km.sup.2 100 Aerostat cylindrical airship E Suspended 15 km Two-balloon airship 58 m 9 m 1 t 40 m 2 km 60,000 m.sup.2 50 Roller (PTL4) with single suspended roller F Suspended 8 km Ellipsoid rigid airship 169 m 27 m 25 t 140 m 2 km 300,000 m.sup.2 30 Roller with multiple suspended rollers *Radius refers to either the radius of the cylindrical airship body (Class A-D), the radius of balloons (Class E), or the maximum radius of an ellipsoid airship (Class F).

[0133] Example 1: Electricity Platform, based on an end-tethered Class A system. Used to generate solar electricity in locations where there is insufficient land for ground-based solar panels. Operated during daylight, and returned to ground at night, and whenever strong winds are forecast. Small and robust enough to enable regular ground handling and storage. A layer of ultrathin photovoltaic film covering 40,000 m.sup.2 of the flat gas envelope generates approximately 40 MWh of energy per day in midlatitudes.

[0134] Example 2: Pole Protector, based on an autonomous Class B system. This long duration system is deployed in polar regions during the summer to shade the ocean adjacent to melting sea ice. It can help preserve multi-season ice floes in areas such as the Beaufort Gyre, where approximately 3,000 systems can reduce net insolation by 1%. The system can be transported between hemispheres during equinoctal periods.

[0135] Example 3: Hydrogen Production Platform based on a Class B system. The Rollable Aerostat is tethered to a surface ship via a central airship. Electricity generated by a layer of ultrathin photovoltaic film, is transmitted to the surface ship and used to electrolyse seawater. Approximately 2,000 tons of hydrogen can be produced each month. The platform operates near each pole for 3 to 4 months during summer, and travels between hemispheres during equinoctal periods.

[0136] Example 4: Interhemispheric Pole Protector based on the Class C or Class D example system. An autonomous long-duration solar reflector which remains in the stratosphere for years at a time. It spends most of its time over the summer pole, but is able to cross the equator during equinoctal periods whilst remaining above the tropopause. Relatively safe from atmospheric disturbance, it still avoids major storms when possible, because of the risk from upper atmospheric lightning, such as the phenomenon known as a blue jet.

[0137] Example 5: Glacier Shade, based on the Class E example system. Used to shade valley walls and debris-covered ice in the vicinity of high-latitude glaciers during summer. It can be transported in component form to a remote location, and assembled and inflated onsite. Carbon fibre composite tethers hold it in position. In mid-summer, it can reduce insolation for a low-albedo area by up to 400 megawatt-hours per day.

[0138] Example 6: Artificial cloud based on the Class F example system. Used to shadow a sensitive area of land or sea during daylight hours. In mid-latitudes in mid-summer, it can reduce insolation for a low-albedo area by up to 2,000 megawatt hours per day.

INDUSTRIAL APPLICABILITY

[0139] The invention can be made in the aerospace industry, and used in the energy, geoengineering or climate adaptation industries.

REFERENCE SIGNS LIST

[0140] The references signs used are as follows: [0141] 101. Depth-constraining structures [0142] 102. Flat envelope [0143] 103. Solar cells [0144] 104. Cylindrical airship [0145] 105. Motors for rotating the cylindrical airship [0146] 106. Central spine of the cylindrical airship [0147] 107. Large gear [0148] 108. Rotating mount [0149] 109. Suspension frame [0150] 110. Counterweight [0151] 111. Ground tether [0152] 112. Power storage [0153] 113. Powered swivel [0154] 114. Thruster [0155] 115. Cable [0156] 116. Gas pipe [0157] 117. Railcar [0158] 118. Rack rail [0159] 119. Guide rail [0160] 120. Unrolling segment of the flat gas envelope [0161] 121. Rolled segment of the envelope [0162] 122. Stacked perforated-pipes [0163] 123. Surface of an airship [0164] 124. Gas cell inside an airship [0165] 125. Fixed pipe shape [0166] 126. Parted perforated-pipes [0167] 127. Semi-rigid aerostat body [0168] 130. Suspended roller [0169] 131. Cylindrical roller [0170] 132. Ellipsoid airship [0171] 133. Keel [0172] 134. Motor for turning the cylindrical roller [0173] 135. Rotary union [0174] 136. General aerostat body, incorporating one or more aerostats [0175] 140. Approximate positions of the tropopause [0176] 141. Polar jet or jet stream [0177] 142. Tropical jet [0178] 143. Box indicating the most accessible part of the lower stratosphere [0179] 150. Connected aerostat of any type [0180] 151. Isolated aerostat of any type (can be optional in smaller systems)

CITATION LIST

Patent Literature

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