|First flight||September 1997|
The Zeppelin NT ("Neue Technologie", German for new technology) is a class of helium-filled airships being manufactured since the 1990s by the German company Zeppelin Luftschifftechnik GmbH (ZLT) in Friedrichshafen. The initial model is the NT07. The company considers itself 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 airships of those days, as well as between the Zeppelin NT and usual non-rigid airships known as blimps. The Zeppelin NT is classified as a semi-rigid airship.
The modern development and construction was financed from an endowment, initially funded with money left over from the earlier Zeppelin company, that had been under the trusteeship of the Mayor of Friedrichshafen. A stipulation on the endowment limited use of its funds to the field of airships. Over the many years, the investment value of the endowment grew to a point where the time seemed right to use it for the design, development, and construction of a new Zeppelin.
The initial design study was prepared in 1989. The ZLT was founded as a spin-off of the Zeppelin company in September 1993. It began to construct a prototype in 1995. The prototype first took to 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 3,600 km in test flights.
In 2001 the company began manufacturing the Zeppelin NT in series and began to exploit the airships commercially. The second ship SN 02 was christened D-LZZR Bodensee on August 10, 2001 and started to give joyrides five days later. By the end of that year, it had already transported 3,222 passengers, a figure that rose to about 30,000 by November 2003.
The Zeppelin NT airships constructed so far are 75 meters (246 feet) long, with a volume of 8,225 m³. They are thus considerably smaller than the old Zeppelins, which reached a maximum volume of 200,000 m³. Furthermore, they are inflated exclusively with the non-flammable noble gas helium, rather than with hydrogen.
In standard operations with a maximum payload, the gas cells do not create enough buoyancy to make the whole ship "lighter-than-air." The negative buoyancy is overcome with engine power. The buoyancy can change when traveling with reduced payload and partially emptied fuel tanks, but usually the Zeppelin NT starts its journey with a net downward force of about 3,000 N (306 kg), and on long trips can end up lighter than air if a lot of fuel is used.
The Zeppelin NT is a semi-rigid airship. It is unlike both the original Zeppelins that had a rigid skeleton and non-rigid blimps. It has an internal triangular truss made of graphite-reinforced plastic and three longitudinal girders made of aluminium which connect the triangular elements along the length of the frame. This frame holds the engines, control car and the steering fins. Additionally, this structure is tightened with aramid cords. It weighs only about 1,000 kg (2,200 pounds).
Inside historical Zeppelins, the gas cells were separate entities from the hull. However, the hull of the Zeppelin NT serves both as the hull and as the gas cell. 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 millibars (0.073 psi) is maintained within the hull. As in blimps, this pressure is kept constant by using ballonets. The ballonets have a total volume of 2,000 cubic metres (71,000 cu ft).
Propulsion and steering 
A trio of Textron Lycoming IO-360 boxer aviation engines with a power of 147 kW (200 hp) each provide the Zeppelin NT with maneuverability. Two lateral engines, equipped with tilting 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. The three 200 PS (197 hp) engines use aviation gasoline as their fuel source.
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.
Flying capabilities 
The design currently has a range of some 900 km (500 nautical miles) and reaches top speeds of 125 km/h (70 knots or 78 mph). 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 (1000 ft), but up to 2,600 m (8,500 ft) is possible. Their maximum permitted takeoff weight is 10,690 kg, with a payload of 1,900 kg.
The Zeppelin NT is able to take-off and land vertically. Only three helpers are required on the ground.
The Zeppelin NT has a passenger capacity of 12, plus 2 crew, or the capability to lift 1,900 kg of payload. In contrast, the original Zeppelin designs carried over a hundred passengers and crew, with a nearly even ratio of passengers to crew members.
Range of application 
The Deutsche Zeppelin-Reederei (German for German Zeppelin shipping company) has offered tours with Zeppelin NT airships since August 15, 2001. The hull surfaces are used for advertising. ZLG founded DZR as a subsidiary in January 2001.
The craft are also used as observation platforms for photographers and television commentators covering major events.
Due to their capability for low-vibration flight (for up to 24 hours), ZLG considers the airships suitable for research missions for environmental observations, troposphere research and natural resources prospecting.
Operational history 
There have been five modern Zeppelins.
D-LZFN Friedrichshafen 
The prototype Zeppelin NT, D-LZFN Friedrichshafen, was intended to be used for training pilots, for special flights and for presentations. 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. It was intended that all further ships would be used commercially or sold. As a tribute to the days of Zeppelin mail, a number of mail-carrying flights were planned. Steve Fossett and Paul Stroehle set the current speed record for airships over a distance of one kilometer on Wednesday, October 27, 2004 in Friedrichshafen, Germany with a Zeppelin NT. The new world record was set to 111.8 km/h (69.5 mph or 60.4 knots), an improvement of 19 km/h.
Starting in late 2005 the Friedrichshafen was based in Jwaneng, a diamond mining town in southern Botswana, where it conducted an airborne geophysical survey on behalf of De Beers Prospecting Botswana. The airship was moved from Amsterdam to Cape Town by ship and then flown to Gaborone where a Lockheed Martin full tensor gravity gradiometer was installed. This instrument, owned and operated by Bell Geospace, measures changes in the Earth's gravity field associated with geological density variations. The technology is based on accelerometers and the data quality is sensitive to the turbulence and motion usually associated with fixed wing aircraft installations. The airship, flying slowly at night in relatively cool calm air, provides a very stable and vibrationally quiet platform. The resulting data is capable of revealing the rather faint gravity signals associated with Kimberlite pipes buried under the Kalahari sands. This survey came to an end on 20 September 2007, when D-LZFN was irreparably damaged by a whirlwind while moored at its mast.
In 2012, a replacement airship, also designated D-LZFN, began its operations. 
D-LZZR Bodensee 
The second Zeppelin NT and first production model (SN 02) was named D-LZZR Bodensee and began the first commercial tourist operations on August 15, 2001 by Deutsche Zeppelin Reederei (DZR). On March 2, 2004 the DZR sold it to Nippon Airship Corporation in Japan. Transferred in June 2004, it was to have followed the historical route of the 1929 World Tour of the famous dirigible LZ127 Graf Zeppelin. After problems with Russian authorities, a special ship for huge parts from the Netherlands was chartered and the Zeppelin was shipped from Italy to Japan by sea. The company used the airship mainly for tours and advertising. In May 2010, due to economic problems at Nippon Airship Corporation, the SN 02 was shipped back to Germany. The ship got back her old name Bodensee and resumed passenger operations in 2012.
D-LZZF Baden-Württemberg 
The third Zeppelin NT (SN03) and second production model, designated D-LZZF Baden-Württemberg, first flew in February 2003. It is currently flown in revenue passenger service by the DZR. It was painted in Goodyear colors for the summer season 2010 to promote a new joint venture between Goodyear and the Zeppelin Luftschiffbau, the first in 70 years.
D-LZNT Eureka 
In January 2006 the Zeppelin Luftschifftechnik GmbH announced construction of a fourth Zeppelin NT07. It was optioned by California-based Airship Ventures in Spring 2007. The new airship completed its first flight on May 21, 2008. On June 26, 2008, ZLT announced that the FAA issued the type certificate for the Zeppelin NT 07, allowing the airship to fly legally in the United States. Prior to the trip to the USA, the airship, registered D-LZNT, operated sightseeing and pleasure flights over eastern London and the Thames Estuary from an airfield close to Upminster, in Essex, England, advertising Stella Artois beer and the DrinkAware campaign. These flights operated between July and September 2008. The airship arrived at the Port of Beaumont on or about September 26, 2008. After spending three days tethered at the Southeast Texas Regional Airport, the airship flew cross-country to its base at Moffett Federal Airfield.  Upon its arrival, the airship was given the US registration N704LZ, and was christened Eureka (after the California state motto). Airship Ventures began commercial operations in November 2008, and offered flightseeing tours over the San Francisco and Monterey Bay areas, operating both out of Moffett Field, and Oakland Terminal. On November 14, 2012, Airship Ventures ceased operations and grounded Eureka.
In May 2011 Goodyear announced it would be replacing its fleet of blimps with three Zeppelin NT airships in the future.
ZLT has also announced plans to build a larger, 19 seat aircraft, called the NT14. The "14" comes from the 14,000 cubic meters of envelope volume.
Data from Jane's All The World's Aircraft 2003–2004
- Crew: 2
- Capacity: 12 passengers or 1,900 kg (4188 lb) payload
- Length: 75.00 m (246 ft 0¾ in)
- Diameter: 14.16 m (46 ft 5½ in)
- Width: 19.50 m (63 ft 11¾ in)
- Height: 17.40 m (57 ft 1 in)
- Volume: 8,255 m3 (290,450 ft3)
- Gross weight: 10,690 kg (23,567 lb)
- Powerplant: 3 × Textron Lycoming IO-360 air-cooled flat-four, 149 kW (200 hp) each each
- Maximum speed: 125 km/h (77 mph)
- Cruising speed: 115 km/h (71 mph)
- Range: 900 km (559 miles)
- Endurance: 24 hours
- Service ceiling: 2,600 m (8,530 ft)
See also 
- Zeppelin Luftschifftechnik GmbH (2008). "Das Luftschiff" (– Scholar search)[dead link]
- FAQs - Zeppelin vs. blimp (retrieved 13 January 2011)
- Manufacturer's FAQ's
- (checked 14 January 2011)
- "Picture of the Zeppelin LZ N07-100 Airship aircraft". Retrieved July 18, 2012.
- "Von der ersten Idee bis zur Serienproduktion – Die chronologische Entwicklung des Zeppelin NT Projektes". Zeppelin Luftschiffteknik (in German). January 26, 2011.
- History of the Zeppelin NT, Zeppelin Luftschifftechnik GmbH & CO KG GmbH, 2011
- Press release on NT #4 option, Air Ship Ventures, June 25, 2007.
- Press release, Air Ship Ventures, 2008-05-21.
- Airship to make appearance in Beaumont, Beaumont Enterprise, 2008-12-08.
- "Zeppelin revival over skies of San Francisco". USA Today. June 22, 2007.
- Goodyear: Zeppelins return at last, UK: The Register, 2011-05-04.
- Jackson 2003, pp. 764–765.
- maximum width
- Jackson, Paul. Jane's All The World's Aircraft 2003–2004. Coulsdon, UK: Jane's Information Group, 2003. ISBN 0-7106-2537-5.
- Sträter, Bernd. Zeppelin NT, in: Khoury, G.A.: Airship Technology. Cambridge, 2nd Edition, 2012 pp. 547-576. ISBN 978-1107019706.
|Wikimedia Commons has media related to: Zeppelin NT|
- Carnet de Vol — Zeppelin NT Company : Friedrichshafen Flights, Zeppelin NT in the World and Technical Data
- Zeppelin Luftschifftechnik GmbH — manufacturers' homepage
- zeppelintours.com — trips to Friedrichshafen and Zeppelin NT airship flights
- Deutsche Zeppelin Reederei — booking joyrides with Zeppelin NT airships in Germany
- Airship Ventures Inc. — U.S. company operating a Zeppelin NT in California