Long March 2F

Long March 2F "Shenjian"
Function	Carrier rocket
Manufacturer	CALT
Country of origin	People's Republic of China
Size
Height	62 metres (203 ft)
Diameter	3.35 metres (11.0 ft)
Mass	464,000 kilograms (1,023,000 lb)
Stages	2
Capacity
Payload to LEO
Mass	8,400 kilograms (18,500 lb)
Associated rockets
Family	Long March
Launch history
Status	Active
Launch sites	SLS, JSLC
Total launches	7
Success(es)	7
First flight	19 November 1999

The Long March 2F (Chinese: 长征二号F火箭 Chang Zheng 2F), also known as the CZ-2F, LM-2F and Shenjian, is a Chinese manned orbital carrier rocket. Designed to launch manned Shenzhou spacecraft, the Long March 2F is a man rated two-stage version of the Long March 2E rocket. It is launched from complex SLS at the Jiuquan Satellite Launch Centre. The Long March 2F made its maiden flight on 19 November 1999, with the Shenzhou 1 spacecraft. After the flight of Shenzhou 3, President Jiang Zemin named the rocket 'Shenjian' meaning 'Divine Arrow'.

On 15 October 2003, a Long March 2F launched Shenzhou 5, China's first manned spaceflight. It has since launched another two manned capsules into orbit.

Differences from the Long March 2E

Externally, the rocket is little different from the Long March 2E from which it was derived. Most of the changes are redundant systems to improve safety, although there are some structural modifications which allow the rocket to support the heavier fairing required by the Shenzhou capsule. The rocket is also capable of lifting heavier payloads with the addition of extra boosters to the first stage.

The rocket also has an "advanced fault monitoring and diagnosis system to help the astronauts escape in time of emergency", and is the first Chinese made rocket to be assembled and rolled out to its launch site vertically.

Vibration issues

During the flight of Shenzhou 5, astronaut Yang Liwei became sick due to heavy vibrations from the rocket. Although the problem was reduced somewhat by modifications to the rocket, vibrations were reported again in Shenzhou 6 necessitating further changes. According to Jing Muchun, chief designer of the Long March 2F "We made changes to the pipelines of the rocket engine, adjusting its frequency. A new design for the pressure accumulator produced evident results. The vibration has now been reduced by more than 50 percent."

Launch History

Date & Time (GMT)	Payload	Outcome	Remarks
19 November 1999, 22:30	Shenzhou 1	Success	First unmanned test of the Shenzhou capsule
9 January 2001, 01:00	Shenzhou 2	Success	Second unmanned test of the Shenzhou capsule, carried live animals
25 March 2002, 14:00	Shenzhou 3	Success	Third unmanned test of the Shenzhou capsule.
29 December 2002, 16:40	Shenzhou 4	Success	Final unmanned test of the Shenzhou capsule.
15 October 2003, 01:00	Shenzhou 5	Success	China's first manned spaceflight
12 October 2005, 01:00	Shenzhou 6	Success	Second manned spaceflight, first with two crew members
25 September 2008, 13:10	Shenzhou 7	Success	Third manned spaceflight, first to feature Extra-vehicular activity

Specifications

• Stage number: 0 - Strap-on boosters x 4
  • Gross mass: 41,000 kg
  • Empty mass: 3,200 kg
  • Thrust (vac): 4 x 814 kN
  • Isp: 291 seconds (2.9 kN·s/kg)
  • Burn time: 128 seconds
  • Diameter: 2.3 m
  • Span: 8.0 m
  • Length: 15.3 m
  • Propellants: N2O4 / UDMH
  • Engines: 1 x YF - 20B per booster = 4

• Stage number: 1 - Core stage
  • Gross mass: 196,500 kg
  • Empty mass: 9,500 kg
  • Thrust (vac): 3,256 kN
  • Isp: 289 seconds (2.8 kN·s/kg)
  • Burn time: 166 seconds
  • Diameter: 3.4 m
  • Length: 23.7 m
  • Propellants: N2O4 / UDMH
  • Engine: 4 x YF - 20B

• Stage number: 2 - Final stage
  • Gross mass: 91,500 kg
  • Empty mass: 5,500 kg
  • Thrust (vac): 831 kN
  • Isp: 289 seconds (2.8 kN·s/kg)
  • Burn time: 300 seconds
  • Diameter: 3.4 m
  • Length: 15.5 m
  • Propellants: N2O4 / UDMH
  • Engine: 1 x YF - 25/23