The introduction of China's new-generation Long March 5 rocket has slipped again, with an industry official saying it is now expected to go into use in 2014.

As recently as October the oxygen-hydrogen launcher, which is in the class of the Delta IV and much larger than the current Long March series, was expected to go into service in 2013. Before that, the Long March 5 was seen as a candidate to launch the second Chinese lunar probe, Chang'e 2, which is now due to be launched "sometime around 2009."

Liang Xiaohong, vice president of China's Academy of Launch Vehicle Technology, revealed the new in-service period in an interview with the official Xinhua news agency.

The Long March 5 will be a family of launchers whose core rocket will have a diameter of 5 meters (16 feet, 5 inches), compared with the 3.35 meters of the current Long March 3. It is to be built at a space industrial base currently under construction at Tianjin and launched from a new facility at Wenchang on Hainan, China's southern island province.

Meanwhile, the unused Long March 3C version of the current generation of Chinese launchers will finally go into service this year, having apparently been shelved after its development was first described about a decade ago.

The Long March 3C is composed of a Long March 3A core rocket with two strap-on boosters. Subsystems are the same as the Long March 3B, which has four strap-on boosters, China said in 1998, when the launch capacity was given as 3.7 metric tons to geostationary orbit.

The rocket that will be launched next month has been in storage since 1998, following the cancellation of its mission to put an Argentine satellite into orbit, the Chinese Academy of Military Sciences told state media. At least one test mission seems to have been done, however, since rocket designer Jiang Jie says Long March 3C has not previously been launched "with a payload."

The launcher was designed for light satellites and wasn't used after the first mission was cancelled because "since then there has been no demand for it," says another official, Sun Jiwen, in remarks also carried by Hong Kong's South China Morning Post newspaper. The Long March 3C will be launched next month from the Xichang base in Sichuan province with an unidentified payload.

The paper quotes Jiang as saying the two strapped-on boosters are likely to generate asymmetric turbulence and that bonding technology for them will be a challenge.