China suffered its first space launch failure in nearly three years, when a three-stage CZ-4C (Long March 4C) launcher rocket failed to deliver its payload to orbit in the early hours of Thursday morning.
It was also the world’s first major space launch failure in 2016, taking place less than 24 hours before a SpaceX Falcon 9 rocket exploded on the launch pad at Cape Canaveral while undergoing static fire test ahead of launch.
The launch mission, though not previously announced, was widely predicted on Chinese social media, based on a Notice to Airmen (NOTAM) issued by the Chinese authority several days before. Multiple sources had identified the mission being Gaofen 10, a high-resolution imagery Earth-observation satellite. The mission would be China’s 13th orbital launch in 2016, and the 235th flight of the Chang Zheng (CZ) launch vehicle family.
The launch was predicted to be around 02:55 CST on 1 September (18:55 UTC on 31 August), from Launch Complex 9 at the Taiyuan Satellite Launch Centre (TSLC), Shanxi Province in central China. However, hours after the launch window had passed, there was no official confirmation of the launch taking place. The North American Aerospace Defence Command (NORAD), which tracks objects in orbit, had not published new two-line element sets (TLEs) indicating the orbiting of any new objects relating to this launch. This led to wide speculations about the mission’s outcome.
Finally, the first clue emerged some 9 hours after the launch, when the local Public Security Bureau (police department) of the neighbouring Shaanxi Province posted on Chinese social media, confirming that rocket stage debris had been spotted and recovered in Shangluo, some 500 km south of the launch centre. This was the first evidence that the launch had taken place.
Further report came in later that day confirming that debris appearing to be part of the launch vehicle’s payload fairing were found in Enshi, Hubei Province, about 970 km downrange from the launch centre. The relatively undamaged debris of rocket stage and payload fairing suggests that the launch vehicle may have suffered a failure in its third-stage.By the afternoon, the Xinhua News Agency-owned CNC website published three photos of the Gaofen 10 launch, confirming the time and payload of the launch mission, but did not mention anything regarding the launch failure. While China’s space programme has always been shrouded in secrecy, in recent years the space authority and industry have become more open about their failures. The most recent two launch failures, the Shijian 11-04 mission in August 2011 and CBERS-3 mission in December 2013, were both reported by state media shortly after launch.
Gaofen 10 is the seventh mission of the Gaofen (“High Definition”) civilian Earth-observation satellite programme for the China High-definition Earth Observation System (CHEOS). Another satellite from the same programme, Gaofen 3, was successfully launched only three weeks before (10 August), also atop a CZ-4C launcher.
The CHEOS is a state-sponsored programme aimed to develop a near-real time, all-weather, global surveillance network consisting of space, near-space, and aerial observation platforms. The programme was originally proposed in 2006 and officially initiated in May 2010, with as many as 14 satellites set for launch between 2013 to 2020.
The Launcher Rocket
The CZ-4C is a three-stage, liquid-fuel launch vehicle developed by Shanghai Academy of Spaceflight Technology (SAST, or 8th Academy) of the China Aerospace Science & Technology Corporation (CASC). First introduced in 2006, the CZ-4C has been mainly used for the launch of large Earth-observation satellites to highly-inclined Sun-Synchronous Orbit (SSO) from either Taiyuan or Jiuquan. All three stages of the launch vehicle burn a bi-propellant with UDMH as fuel and N2O4 as oxidiser. The first- and second-stage of the launch vehicle were based on those of the CZ-2/DF-5, added with a third-stage to place the payload to higher altitude (700—1,000 km).
The launch vehicle is 45.5 metres in length and 3.35 metres in diameter, with a 248.5 metric tons. It is capable of placing up to 2,800 kg payload to SSO, or 4,200 kg to LEO.
The Gaofen 10 mission was the first ever launch failure experienced by the CZ-4C since its introduction in 2006, though a similar CZ-4B rocket suffered a launch failure during the CBERS-3 mission on 9 December 2013.
The Chinese space authority and industry may have hoped that 2016 was going to be a year full of promises and highlights, with up to 20 launch missions including some high-profile missions planned.
In June, the new-generation medium-load CZ-7 launcher rocket made its historical debut flight from the newly-opened Wenchang Space Launch Centre (WSLC) in Hainan Island, successfully orbiting 7 payloads including a subs-scale mock-up crew capsule, a robotic space debris collector, and an in-orbit spacecraft refuelling experiment. Later this year, the new-generation heavy-load CZ-5 will make its debut from the same launch centre. The human spaceflight programme will see the launch of China’s second space laboratory module Tiangong 2 in mid-September, followed by the country’s sixth crewed spaceflight mission Shenzhou 11 a month later for a 30-day stay on the orbital station.
It is highly likely that the latest launch failure will have an impact on the schedule of these missions. Coincidently, a launch failure also occurred shortly before the launch of the first space laboratory Tiangong 1 in 2011, when a CZ-2C rocket launched from Jiuquan failed to deliver the Shijian 11-04 technology satellite into orbit. The incident pushed back the Tiangong 1 launch by nearly a month while engineers investigated the cause for the failure. As a result, the space laboratory module, which had already been checked out and fuelled, had to be stored inside the launch centre’s spacecraft assembly hall during this time.
Currently, the launch campaigns for the Tiangong 2/Shenzhou 11 and CZ-5 missions are both well underway. The Tiangong 2 module was delivered to the Jiuquan Satellite Launch Centre (JSLC) on 9 July, followed by the arrival of two CZ-2F launcher rockets on 6 August, and the Shenzhou 11 spacecraft vehicle on 13 August. At the same time, segments of the CZ-5 heavy-load launcher rocket had just arrived at Hainan Island by sea, and are due to be transported to the Wenchang launch centre to be readied for its debut flight in October—November. The latest launch failure may put a halt on both campaigns to allow time for engineers to rule out the possibility of same issue occurring in these missions.
To the Chinese political leadership and general public, the space programme is not merely a scientific and engineering endeavour, but also closely associated with national pride and international prestige. Launch failures are viewed as national embarrassment and disgrace, and therefore should be avoided at all cost. This attitude has led to an extremely risk-averse approach in the country’s space activities. Programme planners are often willing to sacrifice launch schedule in exchange for better chance of succeeding. While this approach has worked to some degree in the past, it will become increasingly difficult to sustain when China’s launch activities intensify over the coming years.
So far the available evidence appears to suggest that the Gaofen 10 mission failure relates to the launch vehicle’s third-stage. If this is the case, the impact of this failure on other scheduled launch missions may be somewhat limited, given that the stage is unique to the CZ-4B/C family.