US Patent 6,648,272 B1

The KOTHMANN is an advanced vehicle intended to provide Airship operation for a wide range of applications. It is easy to operate, easy to maintain, and easy to build. The intended operational capabilities will satisfy low cost, low altitude flight with simple controls and a high degree of maneuverability and safety.
The Kothmann can repetitively land anywhere and off load without the need for ground crew or mooring facility.

Today there are less than 30 operational airships in the entire world. There should be thousands.

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