China’s new-generation heavy-lift orbital launcher, the CZ-5 (Chang Zheng 5, or Long March 5), will make its maiden flight from the Wenchang Space Launch Centre, on Hainan Island, in early November.
As well as testing the launch vehicle itself, the mission will also place the Shijian 17 (SJ-17) technology experiment satellite into orbit, using the newly-developed YZ-2 (Yuan Zheng-2, or Expedition 2) upper stage.
Segments of the CZ-5 (Y1) launch vehicle were transported inside specially-made oversized containers by the Yuanwang 22 cargo ship to the Qinglan Port, in Sanya, Hainan Island on 22 August, kicking off the two-month launch campaign.
Launch vehicle assembly and payload integration were carried out inside the 15-storey, 99.4 metres-tall ‘501’ Vehicle Assembly Building (VAB) inside the technical area of the Wenchang Space Launch Centre. Segments of the launch vehicle, including its first-stage, second-stage, and four strap-on boosters were hoisted into position by a crane inside the building.
The checkout of the SJ-17 satellite and YZ-2 upper stage was carried out inside the payload assembly building. The payloads enshrined within a two-piece payload fairing were transferred to the VAB for integration with the launcher on 19 October.
The rollout of the launch vehicle took place in the morning of 28 October, at around 08:25 CST. The CZ-5 launch vehicle and payload stack sitting vertically atop the Mobil Launcher Platform moved slowly on a 20-m-wide rail track. It took the platform over two hours to finish the 2,800 m journey from the VAB to Launch Complex 101, where the launch vehicle will be checked out, fuelled, and launched.
The CZ-5 is the most capable and complex launch vehicle ever introduced by China. The development of the launcher began in the early 2000s and took over 10 years to complete. The launcher is fitted with three types of cryogenic liquid engines, all of which are newly developed. The first-stage of the core vehicle is powered by two YF-77 engines burning liquid hydrogen (LH2) as fuel and liquid oxygen (LOX) as oxidiser. The four strap-on stages are each powered by two single-chamber 1,340-kN YF-100 engines burning Kerosene as fuel and liquid oxygen (LOX) as oxidiser. In together these engines produce 10,572 kN (1,078 tonnes) thrust at lift-off.
The second-stage of the CZ-5 is powered by two single-chamber YF-75D engines also burning the LOX/LH2 bi-propellant. This allows the launch vehicle to place up to 14 tonnes of payload to Geostationary Transfer Orbit (GTO).
The CZ-5 (Y1) launch vehicle in the upcoming test flight mission also carries a YZ-2 upper stage, designed to insert multiple payloads into different orbits, or place payload directly to Geostationary Earth Orbit (GEO) without the need to use the satellite’s own propulsion. The YZ-2 is similar in design to the YZ-1A upper stage first tested during the CZ-7 test fight mission in June this year, but features further improvements in performance and capability.
Although China’s space agency did not provide any detail on the SJ-17 satellite, some leaked information from the space industry suggests the satellite will be used to demonstrate ion propulsion and the guidance, navigation and control (GNC) technology required for in-orbit satellite refuelling and repair.
The combined mass of the YZ-2 upper stage and the SJ-17 satellite is estimated to be around 13 tonnes.
A LEO-mission version of the launch vehicle, named CZ-5B, is expected to make its debut flight in 2017.