Todays patent is Kothmann’s only LTA patent.
Kothman describes his invention as follows:
“The airship is simple to assemble from a minimum of six
pre-manufactured assemblies including the lifting gas source.
1) the fabric hull 16,
2) the lifting gas bag 1,
3) the air diaphragm bag 6,
4) the radial triangular frames 5 and
5) the rigid frame assembly comprised of the crew compartment 4,
the equipment deck 17, the radial truss 11, the propulsion
tube 22 and the deck 2.
The rigid frame assembly also includes the propulsion unit and
all other equipment such as the generator, fuel tanks, pumps, fans
and controls. The invention can be field assembled anywhere or
disassembled and transported to remote locations.”
“In the preferred embodiment, the compression ring will be 80
feet in diameter and the airship will be 40 feet in overall height,
although the ship need not be limited to these dimensions. The
size and simplicity of the airship make it ideal for a personal
pleasure craft or recreational vehicle. The craft's controls and motion
through air is more like a submarine in water than other airborne
vehicles. Persons with minimal training and basic navigation skills
can safely operate the airship.”
NOTE: Kothman introduces a unique high-pressure, essentially
lens-shaped airship: Normal pressure 1.5 atmospheres; Compressed
lifting gas stored at up to 200 PSI (pounds per square inch). The
envelope pressure represents a major leap, but the rate, and
possible change of buoyancy due to compression appear to be
reasonably within the current state of the art. Vehicle dynamics
are virtually ignored.
This patent should be required reading for anyone interested in
future airship designs. It cites 18 patents and is already cited
by 20 U S patents, one disclosure, and three foreign patents.
The USPTO only assigned two classifications: 244/30 (Airship)
and 244/97 (Buoyancy varying). The seven approved claims cover,
244/87 (Rudders and empennage),
244/94 (Ballast storage and release),
244/96 (Airship control),
244/98 (Gas bag inflation),
244/100R (Landing gear),
244/115 (Mooring devices),
244/125 (Airship hull construction),
244/126 (Airship skin construction),
244/128 (Airship gas cell construction and arrangements) and
244/130 (Aerodynamic resistance reducing).
N.B. Kothman does not power his airship with his LTA gas,
although he discusses hydrogen as the lifting gas.