Compound aerostat of controllable altitude

• US 4,215,834 A
• Filed: 12/15/1978
• Issued: 08/05/1980
• Est. Priority Date: 12/15/1978
• Status: Expired due to Term

• Current Assignee: the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Dunlap, Richard M.
• Primary Examiner(s): Barefoot, Galen L.
• Application Number:
  US05/969,770
• Time in Patent Office: 599 Days
• Field of Search: 244/30, 244/31, 244/33, 244/96-98, 244/128, 55/70, 55/74, 252/372, 568/840
• US Class Current: 244/97
• CPC Class Codes: B64B 1/62 Controlling gas pressure, heating, cooling, or discharging gas

Abstract

A compound aerostat employing a primary lifting mixture of helium and methanol in a first enclosure and a secondary lifting mixture of ammonia in a second enclosure. Both enclosures are contained within a single envelope. The methanol in the primary enclosure gradually condenses out as the altitude increases yielding a decreasing lift with altitude up to the stratosphere to provide passive altitude stability to the system. An absorbent, metallic lithium is provided within a separate container and connected to controllably absorb the ammonia and thereby control the displacement of the secondary enclosure. The process is reversible with the application of heat by means of propane combustion or solar heating. Other absorbents are LiNO₃, LiCl and CaCl₂. This controllable displacement system can compensate for solar superheat and snow and ice accumulation and facilitate long endurance flights, especially in the troposphere.

Claims

1. A controllable altitude lifting system for an aerostat comprising:

a passive altitude lifting control system including a first enclosure containing a primary gaseous fluid, said primary gaseous fluid having solely passive condensing and vaporizing means controlled by ambient conditions for providing altitude stability, said condensing and vaporizing means comprises methanol; and

an active altitude lifting control system including a second enclosure having a secondary gaseous fluid within, absorbing means connected to controllably absorb said secondary gaseous fluid and dissociation and vaporization means for dissociating and vaporizing the absorbed secondary fluid.

2. A controllable altitude lifting system for an aerostat according to claim 1 having a single envelope containing said first and second enclosures.

3. A controllable altitude lifting system for an aerostat comprising:

a passive altitude lifting control system including a first enclosure containing a primary gaseous fluid, said primary gaseous fluid having passive condensing means for providing altitude stability, said primary gaseous fluid comprises helium and methanol; and

an active altitude lifting control system including a second enclosure having a secondary gaseous fluid within, absorbing means connected to controllably absorb said secondary gaseous fluid and dissociation and vaporization means for dissociating and vaporizing the absorbed secondary fluid, said secondary gaseous fluid comprises ammonia.

4. A controllable altitude lifting system for an aerostat according to claim 3 having a single envelope containing said first and second enclosures.

5. A controllable altitude liting system for an aerostat according to claim 3 wherein said active altitude lifting control system further comprises:

a third enclosure connected to said second enclosure, said third enclosure containing an absorbent for absorbing said ammonia;

heating means for providing heat to said third enclosure for dissociating said ammonia from said lithium and vaporizing said ammonia; and

an agitator located within said third enclosure for enhancing the absorption, dissociation and vaporizing processes.

6. A controllable altitude lifting system for an aerostat according to claim 5 having a single envelope containing said first and second enclosures, and said third enclosure is located outside of said single envelope.

7. A controllable altitude lifting system for an aerostat according to claim 6 wherein said absorbent is selected from the group consisting of lithium, calcium chloride, lithium nitrate and lithium chloride.

8. A controllable altitude lifting system for an aerostat according to claim 6 wherein said absorbent is lithium.

9. An envelope for a limp aerostat comprising:

first and second enclosures;

a primary gaseous fluid contained within said first enclosure, said primary gaseous fluid having solely passive condensing and vaporizing means controlled by ambient conditions for providing altitude stability, said condensing and vaporizing means comprises methanol; and

a secondary gaseous fluid located within said second enclosure capable of being absorbed by one of the group consisting of lithium, calcium chloride, lithium nitrate and lithium chloride.

10. An envelope for a limp aerostat comprising:

first and second enclosures;

a primary gaseous fluid contained within said first enclosure, said primary gaseous fluid having passive condensing means for providing altitude stability, said primary gaseous fluid comprises helium and methanol; and

a secondary gaseous fluid located within said second enclosure capable of being absorbed by one of the group consisting of lithium, calcium chloride, lithium nitrate and lithium chloride, said secondary gaseous fluid comprises ammonia.

11. An envelope for a limp aerostat comprising;

first and second enclosures;

a primary gaseous fluid contained within said first enclosure, said primary gaseous fluid having solely passive condensing and vaporizing means controlled by ambient conditions for providing altitude stability, said condensing and vaporizing means comprises methanol; and

a secondary gaseous fluid located within said second enclosure capable of being absorbed by lithium.

12. An envelope for a limp aerostat comprising:

first and second enclosures;

a primary gaseous fluid contained within said first enclosure, said primary gaseous fluid having passive condensing means for providing altitude stability, said primary gaseous fluid comprises helium and methanol; and

a secondary gaseous fluid located within said second enclosure capable of being absorbed by lithium, said secondary gaseous fluid comprises ammonia.