ChinaSat 1E | Long March 7A

Lift Off Time
September 13, 2022 – 13:18 UTC | 21:18 BJT
Mission Name
ChinaSat 1E (also known as Zhongxing 1E)
Launch Provider
(What rocket company launched it?)
China Aerospace Science and Technology Corporation (CASC)
Customer
(Who paid for this?)
China Satellite Communications
Rocket
Long March 7A
Launch Location
LC-201, Wenchang Space Launch Site, China
Payload mass
5,320 kg (~11,730 lb)
Where did the satellite go?
Geosynchronous Equatorial Orbit (GEO); initial Geosynchronous Transfer Orbit (GTO)
Did they attempt to recover the first stage?
No, the Long March 7A is not capable of booster recovery
Where did the first stage land?
It crashed into the ocean
Did they attempt to recover the fairings?
No, the Long March 7A is not capable of fairing recovery
Were these fairings new?
Yes
This was the:
9th launch of the Long March 7
4th launch of the Long March 7A
116th orbital launch attempt of 2022 (113th successful)
Where to watch
Unofficial replay

How Did It Go?

The China Aerospace Science and Technology Corporation (CASC) — the main contractor working in the Chinese space program — successfully launched the ChinaSat 1E satellite (also Zhongxing 1E, or ZX-1E) atop a Long March 7A rocket, to a geostationary transfer orbit ( GTO). Lift-off took place at the Wenchang Space Launch Site’s Launch Complex 201, in Hainan, China. The spacecraft will operate in a geosynchronous equatorial orbit (GEO).

The Long March 7A Y5 begins its ascent carrying ChinaSat 1E (credit: CASC)

ChinaSat 1E Satellite

Overview On ChinaSat 1

Chinese spacecraft of the 中星1 series — in its native writing, or its rough English equivalent: Zhongxing 1 (ZX 1) — translated as the ChinaSat 1 series have been, or at least very much suspected to be communications satellites for military purposes . Officially, they are regarded as communications and broadcasting satellites providing users with high-quality data, radio, and television transmission services.

ChinaSat 1’s Flight History

Zhongxing appears to be a designation given to the Feng Huo 2 (FH 2) craft, a military satellite. Four of them are now in Earth orbit, as three ChinaSats had been launched before: the 1A, 1C, and 1D (leaving vacant the 1B slot). Each of these flew topping Long March 3B/E carrier rockets, which lifted off from the Xichang Satellite Launch Center. According, this begs the question of whether the change in vehicle and launch pad means the spacecraft has gone through any sort of modification.

Assembly of the ChinaSat 1E satellite on top of the Long March 7A Y5 rocket
ChinaSat 1E inside of the Ø4.2 m fairings being assembled to the Long March 7A Y5 (credit: CASC)

The following table summarizes information on ChinaSat 1 launches and where these machines can now be found in orbit. When comparing dates and times, it becomes evident that the previous three left the planet’s surface at very close times of the day. Given that the fourth flight came from a different location, this could possibly explain this difference.

ChinaSat Abbreviations Launch Date, UTC
[yyyy-mm-dd]
Pad Vehicle Longitude
[°]
Altitude
[km (mi)]
1A ZX 1A (FH 2A) 2011-09-18, 16:33 X LC2 LM 3B/E 129.80 35,794 (22,241)
1C ZX 1C (FH 2C) 2015-12-09, 16:46 X LC3 LM 3B/E 80.17 35,800 (22,245)
1D ZX 1D (FH 2D) 2021-11-26, 16:40 X LC2 LM 3B/E 130.07 35,778 (22,231)
1E ZX 1E (FH 2E) 2022-09-13, 13:18 W LC201 LM 7A TBC TBC
Summary of ChinaSat launches, and references: X – Xichang; W – Wenchang; LM – Long March

Description Of ChinaSat 1E

Developed and manufactured by the China Academy of Space Technology — CAST, a subsidiary of CASC — the spacecraft is based on the DHF-4 bus. It is capable of relaying in C-band and in ultra high frequency (UHF), and of procuring its energy supply by means of two solar arrays and batteries. As a result, it masses at 5,320 kg (11,730 lb), while it features by design an 11-year long lifetime.

Illustration of the Sinosat-2 built on the DHF-4 bus (credit: CASC)

ChinaSat’s Bus

As mentioned before, this satellite was built using a platform — a bus — specifically envisaged for telecommunications tasks: the DHF-4. In its body, a payload with a mass of up to 588 kg (1,296 lb) can be installed, which provides the satellite — the set of both the bus and the payload, the ChinaSat 1E — with the capabilities to carry out its intended job . However, for this to work, the payload requires the bus to count with a series of subsystems, besides its structure. One of them is power supply, in this case achieved through two solar arrays and batteries. Additionally, propulsion is needed for in-space maneuvering, mandatory for reaching the correct stationing in GEO.

Long March 7A

A Brief History Of The New Long Marches

Like many other programs in the spaceflight world, the Chinese space program builds up on heritage knowledge and hardware from the defense sector. Examples of this are the veteran rockets in the family, namely the Long March 2, 3, and 4 — these still have active variants — which drive from the Dong Feng 5 intercontinental ballistic missiles (ICBM).

After decades in service, these hypergolics-propelled launch vehicles are finally, though slowly, heading for retirement. In their stead, a program was delineated to develop and manufacture a new generation of rockets purely conceived with only space applications in mind. The enterprise was assigned to the China Academy of Launch Vehicle Technology (CALT).

Aiming to develop flexible launchers, utilizing more advanced technologies, avoiding the use of highly toxic propellants, and following modularization criteria, the Long March 5 (LM-5) was envisaged, and a series of supplementary vehicles: the Long March 6, 7, and 8. Through the implementation of stages in three basic diameters — 5 m (16.4 ft), 3.35 m (11.0 ft), and 2.25 m (7.4 ft) — housing liquid-fed engines specifically developed for this plan, the newcomers were brought forth.

Long March 5B Y3 with the Ø5 m core stage and Ø3.35 m side boosters (credit: CMSEO)

The Long March 7A

Long March 7A with the Ø3.35 m core stage and Ø2.25 m side boosters (credit: CASC)

Among the younglings, it was the LM-6 that first came into active service, followed about nine months later by its bigger brother: the LM-7 which first flew on June 25, 2016 (four months later, the LM-5). Its derivative, the 长征七号A, or Chang Zheng 7A (CZ-7A) in its anglicised form, debuted about three and a half years later. The Long March 7A is a three-stage medium-lift expendable launch vehicle. With a capability of lofting up to 13,500 kg (29,762 lb) into low-Earth orbit (LEO), and up to 7,000 kg (15,432 lb) into GTO, the whole vehicle masses some 570,000 kg (1,256,634 lb) while measuring 60.1 m) 197 ft tall. At lift off, the rocket can produce up to 7,200 kN of thrust.

Serial # Date, Time UTC
[yyyy-mm-dd]
Payload
Y1 2020-03-16, 13:34 XJY 6
Y2 2021-03-11, 17:51 XJY-6 02
Y3 2021-12-23, 10:16 Shiyan 12-01 & 02
Y5 2022-09-13, 13:18 ChinaSat 1E
Flight history of the Long March 7A rocket

First Stage

The first stage consists of the center core and four liquid propellant boosters, counterintuitively forming a single stage. Such a design feature was considered a good option to reduce the amount of impact points after staging over land — even when for the time being it is only launched from Hainan Island.

The core is 3.35 m (11.0 ft) in diameter and 26.3 m (86.3 ft) in length, presenting a total mass of about 186,500 kg (411,162 lb). Powered by two kerolox — meaning kerosene and liquid oxygen — oxygen-rich staged-combustion-cycle YF-100 engines, the whole core produces roughly 2,400 kN of thrust and burns with a specific impulse (Isp) of 300 s.

Ø2.25 m booster for the Long March 7A (credit: CASC)

Each booster consists of a single YF-100 engine, installed in a module with a diameter of 2.25 m (7.4 ft) and a length of about 26.3 m (86.3 ft). It presents a total mass of 81,500 ft, while it generates a thrust of 1,200 kN, and it burns with an Isp of 300 s. As mentioned, the whole first stage ensemble’s thrust is of about 7,200 kN.

Second Stage

This one is also 3.35 m (11.0 ft) in diameter, but its length is about 8 m (26.2 ft). It totalizes a mass of 70,500 kg (155,426 lb), and it houses four kerolox oxygen-rich staged-combustion-cycle YF-115 engines. Each engine produces 176.5 kN of thrust — resulting in a combined value of 706 kN — has an ISP of 341.5 s, and a chamber pressure of 117 bar.

Third stage

The upper stage of the Long March 7A rocket is derived from the Long March 3B, whose dimensions are 3 m (9.8 ft) in diameter and 12.4 m (40.7 ft) in length. This third stage uses two hydrolox-fed YF-75 engines, producing 78.45 kN of thrust each, and featuring an Isp of 438 s. This makes it one of the most efficient chemical rocket engines, only behind a few others, like the RS-25 with an Isp of 452 s, or the RL-10 with an Isp of 465 s.

Rollout of the Long March 7A Y5 rocket heading to the LC-201 at Wenchang
Rollout of the Long March 7A Y5 (credit: CASC)

Wenchang and Yao 5

All of the Long March 7 and the 7A rockets are launched from the Wenchang Space Launch Site. This facility is managed as a site belonging to the Xichang Satellite Launch Center, therefore the difference in the structure of the name, otherwise identical for the remaining two other centers — the Jiuquan Satellite Launch Center and the Taiyuan Satellite Launch Center. Wenchang offers two launch complexes: no. 1, for the Long March 5 and 5B vehicles, and no. 2, for the Long March 7 and 7A. Each of them is host to only one pad, hence the abbreviated designation LC-201 for the latter.

Painted on the rockets fuselage — more precisely’ on its first stage, between two boosters — the identification Y5, or Yao 5, could be seen. Through this, it is possible to know this was the fifth Long March 7A built. As shown in the previous table, there has not been a flight with a Y4 serial number. This is not uncommon, and could simply mean operations regarding that rocket were delayed for some reason.

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