Long March 2F

Long March 2F

Chang Zheng 2F "Shenjian"
Function	Human-rated orbital launch vehicle
Manufacturer	CALT
Country of origin	China
Size
Height	62 m (203 ft)[1]
Diameter	3.35 m (11.0 ft)[1]
Mass	464,000 kg (1,023,000 lb)[1]
Stages	2
Capacity
Payload to LEO	8,400 kg (18,500 lb)[1]
Associated rockets
Family	Long March
Launch history
Status	Active
Launch sites	SLS, JSLC
Total launches	11
Successes	11
First flight	19 November 1999
Boosters
No boosters	4
Length	15.3 m (50 ft)
Diameter	2.3 m (7 ft 7 in)
Empty mass	3,200 kg (7,100 lb)
Gross mass	41,000 kg (90,000 lb)
Engines	1 YF-20B per booster
Thrust	814 kN (183,000 lbf)
Total thrust	3,256 kN (732,000 lbf)
Specific impulse	291 s (2.85 km/s)
Burn time	128 seconds (2.13 min)
Fuel	N2O4/UDMH
First Stage
Length	23.7 m (78 ft)
Diameter	3.4 m (11 ft)
Empty mass	9,500 kg (20,900 lb)
Gross mass	196,500 kg (433,200 lb)
Engines	4 YF-20B
Thrust	3,256 kN (732,000 lbf)
Specific impulse	291 s (2.85 km/s)
Burn time	166 seconds (2.77 min)
Fuel	N2O4/UDMH
Second Stage
Length	13.5 m (44 ft)
Diameter	3.4 m (11 ft)
Empty mass	5,500 kg (12,100 lb)
Gross mass	91,500 kg (201,700 lb)
Engines	1 YF-24B
Thrust	831 kN (187,000 lbf)
Specific impulse	289 s (2.83 km/s)
Burn time	300 seconds (5.0 min)
Fuel	N2O4/UDMH

The Long March 2F (Chinese: 长征二号F火箭 Changzheng 2F), also known as the CZ-2F, LM-2F and Shenjian,^[1] is a Chinese orbital carrier rocket, part of the Long March rocket family. Designed to launch crewed Shenzhou spacecraft, the Long March 2F is a human-rated two-stage version of the Long March 2E rocket, which in turn was based on the Long March 2C launch vehicle.^[2] 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, CPC General Secretary and President Jiang Zemin named the rocket 'Shenjian' meaning 'Divine Arrow'.^[3]

On 15 October 2003, a Long March 2F launched Shenzhou 5, China's first human spaceflight. It has since launched the Shenzhou 6, Shenzhou 7, Shenzhou 9, and Shenzhou 10 missions into orbit.^[4]

Differences from the Long March 2E

Externally, the rocket is similar 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.^[5]

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.^[6]

Vibration issues

During the Shenzhou 5 flight, Yang Liwei became unwell 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." ^[7]

Launch history

References

Long March rockets LM 1 family Long March 1 1D LM 2 family Feng Bao 1 Long March 2A 2C 2D 2E 2E(A) 2F LM 3 family Long March 3 3A 3B 3B/E 3B(A) 3C LM 4 family Long March 4A 4B 4C LM 5 family Long March 5 LM 6 family Long March 6 LM 7 family Long March 7 LM 8 family Long March 8 LM 9 family Long March 9 LM 11 family Long March 11 List of Long March launches China Academy of Launch Vehicle Technology