Systems and Methods for Long Endurance Airship Operations

• US 20130037650A1
• Filed: 09/20/2012
• Published: 02/14/2013
• Est. Priority Date: 03/15/2011
• Status: Active Grant

• Current Assignee: Stratospheric Airships LLC
• Original Assignee: Stratospheric Airships LLC
• Inventors: Heppe, Stephen B.
• Granted Patent: US 9,139,279 B2
• Time in Patent Office: Days
• US Class Current: 244/2
• CPC Class Codes: B64B 1/54 connecting two or more balloons in superimposed relationship
• CPC Class Codes: B64C 37/02 Flying units formed by separate aircraft towing B64D3/00; aircraft transported by aircraft B64D5/00; air-refuelling B64D39/00

Abstract

In one example, a long endurance airship system includes a payload airship and a first logistics airship mechanically joined to the payload airship to form a first combined airship, the payload airship and the logistics airship having design capabilities differing by at least a factor of two with regard to at least one of: power generation capability, propulsion capability, endurance capability, and lift capability, in which the first combined airship is free flying, lighter-than-air, and configured to maintain aloft for greater than 30 days without physical connection to the ground. Illustrative methods for long endurance airship operations are also provided.

Claims

1. A long endurance airship system comprising:

a payload airship; and

a first logistics airship mechanically joined to the payload airship to form a first combined airship, the payload airship and the logistics airship having design capabilities differing by at least a factor of two with regard to at least one of;

power generation capability, propulsion capability, endurance capability, and lift capability;

in which the first combined airship is free flying, lighter-than-air and configured to remain aloft for greater than 30 days without physical connection to the ground.

2. The system of claim 1, in which the first combined airship is configured for stationkeeping at a predetermined station during meteorological conditions with wind speeds below a predetermined threshold;

the system further comprising a reconfiguration of the first combined airship to form a second combined airship comprising the payload airship and at least a second logistics airship, the second combined airship being configured for stationkeeping at the predetermined station in meteorological conditions with wind speeds above the predetermined threshold.

3. The system of claim 1, in which the first combined airship operates at an altitude above 15 kilometers.

4. The system of claim 1, in which the payload airship and first logistics airship are mechanically joined with a flexible umbilical adapted to support the transfer of at least one of:

electrical power, lifting gas, other gases, liquid fuel, other liquids, and data.

5. The system of claim 4, in which the combined airship is adapted to support a drafting mode of flight that reduces drag on the combined airship to a value that is less than the sum of the drags on the two airships individually.

6. The system of claim 1, in which the payload airship and the first logistics airship are reversibly mated together, in which the payload airship and first logistics airship support rendezvous, mating, and demating, while in flight.

7. The system of claim 1, in which a mate between the payload airship and first logistics airship is configured to transfer structural loads between the payload airship and the first logistics airship.

8. The system of claim 1, in which the first combined airship has at least twice the station keeping endurance of the payload airship alone, in the same meteorological conditions.

9. The system of claim 1, further comprising a second logistics airship configured to reversibly mate with the payload airship.

10. A free-flying, lighter-than-air, combined airship comprising:

a lower airship;

an upper airship; and

a tether connecting the lower airship and the upper airship;

in which;

the upper airship is configured to be equiliberally buoyant, while carrying the tether, in a first altitude range; and

the lower airship is configured to be equiliberally buoyant in a second altitude range while carrying a payload, the first altitude range being higher than the second altitude range, such that the upper airship is at least one kilometer above the lower airship and the tether mechanically transmits drag forces and lift forces between the airships.

11. The system of claim 10, in which the first altitude range is between 20 and 50 kilometers above sea level and the second altitude range is between 10 and 30 kilometers above sea level.

12. The system of claim 10, further comprising a balloon shuttle configured to:

travel up the tether toward the upper airship while carrying a payload of lifting gas for the upper airship; and

travel down the tether toward the lower airship after delivering a payload of lifting gas to the upper airship.

13. The system of claim 12, in which the lower airship comprises a supply of lifting gas for transfer to the balloon shuttle.

14. The system of claim 10, in which the lower airship is configured to receive replenishment from a logistics airship, the replenishment comprising at least one of:

fuel, lifting gas, and new payloads.

15. The system of claim 10, in which the lower airship comprises a mated pair of a payload airship and a logistics airship, wherein said payload airship is configured to be equiliberally buoyant in said second altitude range while carrying a payload, and said logistics airship is configured to be equiliberally buoyant in a third altitude range that at least partially overlaps said second altitude range, in which a lower end of the tether is connected to the payload airship.

16. The system of claim 10, in which the lower airship comprises a mated pair of a payload airship and a logistics airship, wherein said payload airship is configured to be equiliberally buoyant in said second altitude range while carrying a payload, and said logistics airship is configured to be equiliberally buoyant in a third altitude range that at least partially overlaps said second altitude range, in which a lower end of the tether is connected to the logistics airship.

17. The system of claim 10, wherein at least one of the airships further comprises an apparatus to adjust its angle of attack relative to the wind.

18. The system of claim 10, wherein at least one of the airships further comprises a parachute to provide a controllable amount of drag, wherein the parachute is connected to one of:

the airship, the tether connected to the airship, or the airship and the tether.

19. The system of claim 10, wherein at least one of the airships further comprises a parafoil to provide a controllable amount of lift and drag wherein the parafoil is connected to one of:

the airship, the tether, or the airship and the tether.

20. The system of claim 10, in which at least two of the airships further comprise both a parachute and parafoil to provide by their joint operation a controllable amount of lift and drag.

21. The system of claim 10, in which at least one of the airships attached to the tether comprises a tether deployment and retraction mechanism adapted to deploy and retract the tether to a controllable length.

22. The system of claim 21, further comprising a heater adapted to warm the tether as the tether is deployed from and retracted into said deployment and retraction mechanism.

23. A method for providing aeronautical operations with a free-flying lighter-than-air, combined airship, the method comprising:

monitoring available resource reserves of at least one of;

fuel, lifting gas, or stored energy capacity of the combined airship while the combined airship is airborne, wherein the combined airship comprises at least two airships, wherein at least one airship is adapted to mate and demate from at least one other airship while in flight and wherein capabilities of the combined airship with regard to achievable thrust, achievable lift, and achievable drag, in various meteorological conditions, are known within uncertainty limits;

forecasting future meteorological conditions along a projected route of the combined airship;

determining if the available resource reserves and capabilities of the combined airship are sufficient for operation along the projected route over a planning period during the forecasted meteorological conditions;

if the available resource reserves and capabilities of the combined airship are not sufficient to operate along the projected route over the planning period, launching a relief logistics airship to provide additional resources, the additional resources comprising at least one of;

additional thrust capability, additional fuel, additional lifting gas, additional stored energy, additional energy capacity, or additional electrical power; and

performing rendezvous and reconfiguring the combined airship to include resources from the relief logistics airship such that the reconfigured combined airship has additional resources and capabilities for operation along the projected route.

24. The method of claim 23, in which the additional resources are sufficient for operation along the projected route during the forecasted meteorological conditions over the planning period.

25. The method of claim 23, in which the combined airship comprises a mated pair of a first logistics airship and a payload airship, where reconfiguring the combined airship comprises at least one of:

mating the relief logistics airship to the first logistics airship which is mated to the payload airship;

demating the first logistics airship from the payload airship and mating the relief logistics airship to the payload airship;

transferring lifting gas from the relief logistics airship to the first logistics airship;

transferring lifting gas from the relief logistics airship to the payload airship;

transferring fuel from the relief logistics airship to the first logistics airship;

transferring fuel from the relief logistics airship to the payload airship;

transferring electrical power from the relief logistics airship to the first logistics airship; and

transferring electrical power from the relief logistics airship to the payload airship.

26. The method of claim 23,

in which the combined airship comprises an upper airship at a first altitude and a lower airship at a second altitude, the upper airship and the lower airship being connected by a tether, in which the first altitude and second altitude are vertically separated by at least five kilometers;

and

in which operation along the projected route comprises altering the aerodynamic characteristics of at least one of the upper airship and lower airship to reduce the rate of energy consumption of the combined airship needed to operate along the projected route.

27. The method of claim 26, in which winds at the first altitude and winds at the second altitude are traveling in substantially different directions and in which altering the aerodynamic characteristics of the combined airship comprises at least one of:

altering the heading of one of the airships, deploying a parachute, altering aerodynamic characteristics of the parachute, deploying a parafoil, altering the aerodynamic characteristics of the parafoil, and changing at least one of the first altitude and the second altitude.

28. The method of claim 26, further comprising replenishing lifting gas in the upper airship by:

inflating a balloon shuttle with lifting gas;

moving the balloon shuttle upward along the tether toward the upper airship; and

transferring the lifting gas from the balloon shuttle to the upper airship.

29. The method of claim 26, wherein the lower airship comprises a mated pair of a first logistics airship and a payload airship, wherein reconfiguring the combined airship comprises at least one of:

demating the first logistics airship from the payload airship;

mating the relief logistics airship to the payload airship;

mating the relief logistics airship to the first logistics airship which is mated to the payload airship;

transferring lifting gas from the relief logistics airship to the first logistics airship;

transferring lifting gas from the relief logistics airship to the payload airship;

transferring fuel from the relief logistics airship to the first logistics airship;

transferring fuel from the relief logistics airship to the payload airship;

transferring electrical power from the relief logistics airship to the first logistics airship;

or

transferring electrical power from the relief logistics airship to the payload airship.

30. The method of claim 26, wherein at least one of the first altitude and the second altitude comprise a stratospheric altitude.

31. The method of claim 23, where the projected path comprises at least one of:

a route between waypoints, stationkeeping at a station, stationkeeping within a range around a station, and stationkeeping at a station by traveling a route around the station.

32. The method of claim 23, wherein reconfiguring the combined airship to include resources from the relief logistics airship comprises a soft mate between the combined airship and the relief logistics airship.

33. The method of claim 23, wherein reconfiguring the combined airship to include resources from the relief logistics airship comprises a hard mate between the combined airship and the relief logistics airship, wherein resources from the relief logistics airship comprise propulsive force transferred through the hard mate.

34. A method of providing logistics support to at least one free-flying payload-carrying airship with endurance greater than 30 days, the method comprising:

providing a plurality of logistics airships that are adapted to provide logistics support to the at least one free-flying payload-carrying airship, and

dispatching at least one of said logistics airships to the at least one free-flying payload-carrying airship to provide logistics support.

35. The method of claim 34, wherein the logistics support comprises at least one of:

fuel replenishment for propulsion or power generation, lifting gas replenishment, change-out of payloads, delivery of a payload airship, return of a payload airship to the ground, provision of thrust, or replacement of an existing logistics airship in a combined airship.

36. The method of claim 34, wherein the free-flying payload-carrying airship comprises one of:

a single airship carrying a payload, a combined airship comprising a mated combination of at least one logistics airship and at least one payload airship, or a tethered airship comprising an upper airship and a lower airship where the lower airship one of;

a single airship or a mated combination of at least one logistics airship and a payload airship.

37. The method of claim 34, wherein a plurality of free-flying payload-carrying airships receive logistics support from the plurality of logistics airships.

38. The method of claim 34, wherein the plurality of free-flying payload-carrying airships are not all identical with respect to size, weight, design, or payload, and at least one of the logistics airships is designed to mate with at least two of the non-identical payload-carrying airships.

39. The method of claim 38, wherein a plurality of logistics airships are each designed to mate with a plurality of non-identical free-flying payload-carrying airships.

40. The method of claim 34, wherein the plurality of logistics airships are not all identical to one another and each is configured to provide logistics services with respect to at least one of:

fuel replenishment, lifting gas replenishment, change-out payloads, delivering a payload airship to an operational altitude, returning the payload airship to the ground, and thrust.

41. The method of claim 34, wherein the dispatch of the logistics airship is responsive to a request from a customer.

42. The method of claim 34, wherein the dispatch of the logistics airship is responsive to a decision process based on telemetry data originated from the free-flying payload-carrying airship.