Zeppelin NT
Zeppelin NT ("Neuer Technologie", German for new technology) is an airship type that has been manufactured since the 1990s by the German company Zeppelin Luftschifftechnik GmbH (ZLG) in Friedrichshafen.This company can be considered the successor of the companies founded by Ferdinand von Zeppelin which constructed and operated the very successful Zeppelin airships in the first third of the 20th century. There are, however, a number of notable differences between the Zeppelin NT and the dirigibles of those days, as well as between the Zeppelin NT and usual non-rigid airships known as blimps.
The Zeppelin NT airships constructed so far have a length of 75 m and a volume of 8225 m³. They are thus considerably smaller than the old Zeppelins. Furthermore, they are inflated exclusively with the non-flammable noble gas helium.
In standard operation mode, the filling does not create enough buoyancy to make the whole ship "lighter-than-air", which is compensated for with engine power. It is therefore considered a hybrid airship. This condition can change when traveling with reduced payload and partially emptied fuel tanks, but usually the Zeppelin NT flies with a remaining downward force corresponding to about 300 kg.
The Zeppelin NT is a semi-rigid airship, contrary to its predecessors which had a complete rigid skeleton, as well as to non-rigid blimps. It is fitted with a carbon fiber support structure of triangular cross-section and three longitudinal girders made of aluminium to which engines, the control car and the steering fins are attached. Additionally, this structure is tightened with aramid cords. It has an approximate mass of only 1000 kg.
While within the hull of the historical Zeppelins the gas cells were separate entities, the hull of the Zeppelin NT serves both purposes. It is made of a three-layered laminate: one gas-tight layer of Tedlar (PVF), one polyester fabric layer to provide stability and one polyurethane layer suitable for thermic welding that serves to connect the separate laminate panels.
To preserve its outer form, a slight overpressure of about 5 millibar is maintained within the hull. Like in blimps, this pressure is kept constant using ballonets, which have a total volume of 2,000 m³.
Three propeller engines of the type Textron Lycoming IO-360 with a power of 147 kW (197 hp) each provide the Zeppelin NT with excellent maneuverability. Two lateral engines, equipped with tearing propellers and usually aligned horizontally, can be turned 90° upward or 30° downward. The aft engine powers a pushing propeller that can be turned 90° downward, as well as a steering propeller directed to the side and working similarly to the lateral-thrust units of some ships.
Instead of four rudder and elevator fins, the Zeppelin NT uses only three, which saves weight. As a side effect, the loss of one fin can be compensated with the remaining two.
The controls are implemented in fly-by-wire technology, with the pilot using a joystick to steer in three dimensions.
The craft currently have a range of some 900 km and reach top speeds of 125 km/h. The standard cruising speed of 70 km/h for tourist flights can be attained using the rear propeller only. Standard operational altitude is 300 m, but up to 2,600 m is possible. Their maximum permitted takeoff weight is 10,690 kg, with a payload of 1900 kg.
The Zeppelin NT is able to start and land vertically, and only three helpers are required on the ground.
Since August 15 2001 the Deutsche Zeppelin Reederei (German for German Zeppelin shipping company), founded as a subsidiary company of the ZLG in January 2001, successfully offers joyrides with Zeppelin NT airships. The hull surfaces are marketed as advertising space.
Additionally, the craft are used as observation platforms for photographers and television commentators covering major events. Due to their capability for long low vibration flight (up to 24 hours), the ZLG considers the airships well-suited to research missions for environmental observations, troposphere research or prospecting natural resources.
The initial design study was prepared in 1989. The ZLG was founded as a spin-off of the Zeppelin company in September 1993 an began to construct a prototype in 1995 which first took the air in September 1997.
On July 2 2000, the centennial of the first Zeppelin flight, the prototype SN 01 was christened D-LZFN Friedrichshafen. Subsequently, it traveled some 3600 km in test flights.
In 2001 the company began manufacturing the Zeppelin NT in series and to exploit the airships commercially. The second ship SN 02 was christened D-LZZR Bodensee on August 10 2001 and started to operate joyrides five days later. By the end of that year, it had already transported 3222 passengers, a figure that rose to about 30,000 by November 2003.
During the Oktoberfest of 2002 a Zeppelin NT was used for radio experiments in connection with the European Galileo positioning system project for the German Aerospace Center and the ESA.
The third Zeppelin NT SN 03 was designated D-LZZF and first flew in February 2003.
The Friedrichshafen is intended to be used for training pilots, for special flights and for presentation, while all further ships will be used commercially or sold. As a tribute to the days of Zeppelin mail, a number of mail-carrying flights are planned.
On March 2 2004 the ZLG sold a Zeppelin NT for the first time. SN 02 was acquired by the Japanese Nippon Airship Corporation and will be transferred in June 2004, following the historical route of the 1929 world tour of the famous dirigible LZ127 "Graf Zeppelin". The company intends to use the airship mainly for joyrides and advertising.
Technology
Hull
Propulsion and steering
Flying capabilities
Range of application
Project history
External links