Collapsible, transportable, composite shelter and hyperbaric chamber

A shelter in the form of a tubular structure with closeable openings at each end. Material is to be a lightweight core, such as PVC or Rohacell foam, sandwiched between two skin layers, each of which consists of fiberglass, carbon fiber, or aramid fiber. Form is to be several sections that can be expanded and contracted telescopically thereby allowing for transport as a backpack while contracted, and shelter for a supine adult while expanded. The sections are to be linked and not independent or free-standing. The sections at either end are to have rigid doors that allow access to the shelter interior. When fully expanded, the sections lock together providing for an airtight, rigid structure. This structure may serve as shelter and hyperbaric chamber for treatment of illnesses such as those resulting from exposure to low barometric pressures at high altitudes (e.g., HACE, HAPE). The structure can be fitted with a pump and a pressure release valve, which allow for control of barometric pressure to relieve such ailments associated with high altitudes. The shelter takes the place of separate backpack, tent or other shelter, insulating pad, sleeping bag, and transportable hyperbaric device.