In the 1990s the Zeppelin company returned to the airship business. Their new model, designated the Zeppelin NT, made its maiden flight on 18 September 1997. there were four NT aircraft flying, a fifth was completed in March 2009 and an expanded NT-14 (14,000 cubic meters of helium, capable of carrying 19 passengers) was under construction. One was sold to a Japanese company, and was planned to be flown to Japan in the summer of 2004. Due to delays getting permission from the Russian government, the company decided to transport the airship to Japan by sea. One of the four NT craft is in South Africa carrying diamond detection equipment from De Beers, an application at which the very stable low vibration NT platform excels. The project included design adaptations for high temperature operation and desert climate, as well as a separate mooring mast and a very heavy mooring truck. NT-4 belonged to Airship Ventures of Moffett Field, Mountain View in the San Francisco Bay Area, and provided sight-seeing tours.