Long March 7

Tianzhou 2 | Long March 7

Lift Off Time
May 29, 2021 – 12:55 UTC | 20:55 BJT
Mission Name
Tianzhou 2
Launch Provider
(What rocket company launched it?)
China Aerospace Science Corporation (CASC)
Customer
(Who paid for this?)
China National Space Administration (CNSA)
Rocket
Long March 7
Launch Location
LC-201, Wenchang Satellite Launch Center, Hainan Island, China
Payload mass
6,023 kg (13,278 lb)
Where did the spacecraft go?
Low earth orbit (LEO) – 370 km (230 mi), at a 41.0° inclination
Did they attempt to recover the first stage?
No, this is not a capability of the Long March 7
Where did the first stage land?
It crashed into the ocean
Did they attempt to recover the fairings?
No, this is not a capability of the Long March 7
Were these fairings new?
Yes
This was the:
1st resupply mission for the Tiangong 3 Space Station
– 2nd launch of a Tianzhou spacecraft
– 5th mission of a Long March 7 rocket
– 48th orbital launch attempt in 2021 (46th successful launch)
Where to watch
If available, a replay will be listed here

How did it go?

The China Aerospace Science Corporation (CASC) successfully launched it’s first cargo resupply mission, the Tianzhou 2, to the new Tiangong 3 Space Station, currently under construction in low earth orbit (LEO). The rocket launched from LC-201, Wenchang Satellite Launch Center, in China on May 29, 2021, at 12:55 UTC. The spacecraft then docked to the Tianhe module’s aft docking port just 8 hours after lift off, at 21:01 UTC, a new record for China’s space program.

The rocket was initially scheduled to launch on May 19, 2021, but was delayed twice due to technical reasons. The exact cause has not been disclosed.

What is the Tianzhou 2 Mission?

The Tianzhou 2 mission was the first cargo resupply mission to the Tianhe Core Crew module (CCM) of China’s new and developing Tiangong 3 Space Station. The spacecraft delivered 4,254 kg (9,378 lb) of pressurized cargo to the Tianhe CCM, comprised of supplies for the stations future astronauts, and included two EVA spacesuits. It also carried 1,769 kg (3,900 lb) of propellant to the module, enough to autonomously refuel and maintain the module’s orbital altitude.

The Tianzhou (which means “heavenly boat”) is an automated cargo spacecraft which will function as the main resupply vehicle for the Tiangong 3 Space Station. The spacecraft was developed from China’s first prototype space station, the Tiangong 1. The first Tianzhou spacecraft, the Tianzhou 1, launched on a Long March 7 rocket from Wenchang on April 2017.

While it has not been confirmed how long the Tianzhou 2 will remain docked to the Tianhe CCM, another cargo resupply mission, the Tianzhou 3, is scheduled to launch in September 2021, and will require the aft docking port to be free.

Tianzhou 1 spacecraft, artist concept
An artist’s impression of the Tianzhou-1 spacecraft. (Credit: China Aerospace Science and Technology Corporation)

The Tiangong 3 Space Station

The Tiangong 3 Space Station (meaning “heavenly palace”) is a space station currently under construction in low earth orbit (LEO). When complete the station will be roughly one-fifth the mass of the of the International Space Station. Construction began on April 29, 2021, when the core module, the Tianhe, which is able to accommodate three crew members with a built-in life support system, was launched on a Long March 5B rocket.

China’s aim is to construct the three-module space station with 11 launches across 2021-2022, which will include 3 module launches, 4 cargo spacecraft, and 4 crewed missions. The station will be comprised of three modules, though it has the ability to expand to 6, and it is expected to be operational for at least 10 years. The first crewed flight to the station is scheduled to take place in June 2021.

What is the Long March 7?

The Long March 7 is a three stage medium lift launch vehicle, capable of placing a 13,500 kg (~29,800 lb) payload into low earth orbit (LEO), or a 7,000 kg (~15,000 lb) payload into geostationary transfer orbit (GTO).

The basic version of the Long March 7 can be customized by varying the number of boosters, allowing it to be capable of reaching higher orbits or executing multiple orbital deployments.

Long March 7, launch pad, Tianzhou 2
The Long March 7 (Credit: Xinhua News)

Boosters

The center core of the Long March 7 can be supported by either 0, 2, or 4 boosters, which use refined kerosene (RP-1) and liquid oxygen (LOx) propellent. The boosters are powered by an oxidizer-rich staged combustion YF-100 engine. At sea level, each booster provides 1,200 kN (270,000 lbf) of thrust. This increases to 1,340 kN (300,000 lbf) of thrust in vacuum.

First Stage

The center core of the rocket is 3.35 meters in diameter and has two YF-100 engines. Like the boosters, this first stage uses refined kerosene (RP-1) and liquid oxygen (LOx) propellant. At sea level, this stage produces 2,400 kN (540,000 lbf) of thrust, increasing to 2,680 kN (600,000 lbf) at vacuum.

Second Stage

Similarly to the first stage, the second stage is also 3.35 meters in diameter and uses refined kerosene (RP-1) and liquid oxygen (LOx) propellant. This stage is powered by 4 oxidizer-rich staged combustion YF-115 engines, two of which are fixed and two of which are able to gimble. In vacuum the second stage offers 706 kN (159,000 lbf) of thrust.

Third Stage

The Long March 7 does not have a third stage in the basic configuration used for this mission, but the Long March 7A variant has an additional third stage powered by liquid hydrogen (LH2) and liquid oxygen (LOx). The stage uses 2 YF-75 engines, which produce 167 kN (37,580 lbf) of thrust and have an ISP of 438 seconds.

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