Long March 3B

Long March 3B

The launch of a Long March 3B carrier rocket at Xichang Satellite Launch Center
Function	GTO Carrier rocket
Manufacturer	CALT
Country of origin	People's Republic of China
Size
Height	3B: 54.838 metres (179.91 ft)[1] 3B/E: 56.326 metres (184.80 ft)[2]
Diameter	3.35 metres (11.0 ft)[1]
Mass	3B: 425,800 kilograms (939,000 lb)[1] 3B/E: 458,970 kilograms (1,011,900 lb)[2]
Stages	3
Capacity
Payload to LEO	12,000 kilograms (26,000 lb)[3]
Payload to SSO	5,700 kilograms (13,000 lb)[3]
Payload to GTO	3B: 5,100 kilograms (11,000 lb)[3] 3B/E: 5,500 kilograms (12,000 lb)[2]
Payload to GEO	2,000 kilograms (4,400 lb)[3]
Payload to HCO	3,300 kilograms (7,300 lb)[3]
Associated rockets
Family	Long March
Derivatives	Long March 3C
Launch history
Status	Active
Launch sites	LC-2, XSLC
Total launches	3B: 10 3B/E: 7
Successes	3B: 9 3B/E: 7
Failures	3B: 1
Partial failures	3B: 1
Maiden flight	3B: 14 February 1996 3B/E: 13 May 2007
Boosters (Stage 0)
No boosters	4
Length	15.326 m
Diameter	2.25 m
Engines	YF-25
Thrust	740.4×4 KN
Specific impulse	(2556.2 N-s/kg)
Fuel	N2O4/UDMH
First Stage
Length	23.272 m
Diameter	3.35 m
Engines	4 YF-20C
Thrust	2961.6 KN
Specific impulse	(2556.2 N-s/kg)
Fuel	N2O4/UDMH
Second Stage
Length	9.943 m
Diameter	3.35 m
Engines	YF-24E YF-22E (Main) YF-23C (Vernier)
Thrust	742 KN (Main) 11.8×4 KN (Vernier)
Specific impulse	2922.57 N-s/kg (Main) 2910.5 N-s/kg (Vernier)
Fuel	N2O4/UDMH
Third Stage
Length	12.375 m
Diameter	3.00 m
Engines	YF-75
Thrust	78.5×2 KN
Specific impulse	(4312 N-s/kg)
Fuel	LOX/LH2

The Long March 3B (Chinese: 长征三号乙火箭), also known as the Chang Zheng 3B, CZ-3B and LM-3B, is a Chinese orbital carrier rocket. Introduced in 1996, it is launched from Launch Area 2 at the Xichang Satellite Launch Centre. A three-stage rocket with four strap-on liquid rocket boosters, it is most powerful member of the Long March rocket family and the heaviest of the Long March 3 rocket family, and is mainly used to place communications satellites into geosynchronous orbits. At the time of its introduction, it was the second most capable expendable launch system in the world, only after the Russian Proton.^[4] An enhanced version, the Long March 3B/E was developed to increase GTO capacity and lift heavier GEO communications satellites.

History

Drawing of Long March 3B

The development of the Long March 3B was started in 1986 on the basis of the prior technology of Long March launch vehicles to meet the demand of international GEO communications satellite market, especially for high power and heavy communications satellites. During its maiden flight on 14 February 1996, the rocket suffered a guidance failure two seconds into the flight and pitched over, crashing into a nearby village 22 seconds after launch. The Intelsat 708 satellite was lost and as many as 100 villagers were killed.^{[citation needed]} Following its maiden flight, the next ten launches of Long March 3B and 3B/E rockets were successful. In 2009, a Long March 3B partially failed during the launch due to a third stage anomaly which resulted in Palapa-D reaching a lower than planned orbit.^[5] However, the satellite was able to maneuver itself into the planned orbit.

Long March 3B

The Long March 3B is the most powerful launch vehicle in Long March fleet and is based on the Long March 3A as its core stage with four liquid boosters strapped on the first stage. Its LEO capacity is 12,000 kilograms (26,000 lb) and GTO capacity is 5,100 kilograms (11,000 lb). It has been launched nine times so far.

Long March 3B/E

The Long March 3B/E is an enhanced Long March 3B, which features an enlarged first stage and boosters, which increase its GTO payload capacity to 5,500 kilograms (12,000 lb).^[6] Its maiden flight was on 13 May 2007, when it successfully launched NigComSat-1, the first African geosynchronous communications satellite. It was also used for launching Venesat-1 in 2008.Launched the Pakistan communication satellite PAKSAT 1R on 11-08-2011.

Long March 3C

Main article: Long March 3C

A modified version of the Long March 3B, the Long March 3C, was developed in the mid-1990s to bridge the gap in payload capacity between the Long March 3B and 3A. It is almost identical to the Long March 3B but with two boosters instead of four, which results in a reduced GTO payload capacity of 3,800 kilograms (8,400 lb). Its first launch was on 25 April 2008. ^[4]

References

1. ^ ^{a b c} Mark Wade. "CZ-3B". Encyclopedia Astronautica. http://www.astronautix.com/lvs/cz3b.htm. Retrieved 2008-04-26. 
2. ^ ^{a b c} http://www.cgwic.com/LaunchServices/LaunchVehicle/LM3B.html
3. ^ ^{a b c d e} Gunter Krebs. "CZ-3B (Chang Zheng-3B)". Gunter's Space Page. http://space.skyrocket.de/doc_lau_det/cz-3b.htm. Retrieved 2008-04-26. 
4. ^ ^{a b} http://www.sinodefence.com/space/launcher/changzheng3.asp
5. ^ "“帕拉帕－Ｄ”通信卫星未能进入预定轨道". Xinhua. 2009-08-31. http://news.xinhuanet.com/mil/2009-08/31/content_11973441.htm. Retrieved 2009-08-31. 
6. ^ "LM-3B". China Great Wall Industry Corporation. http://www.cgwic.com/LaunchServices/LaunchVehicle/LM3B.html. Retrieved 2009-08-31. 

External links

• LM-3B User's Manual GlobalSecurity.org - Long March Launch Vehicle User's Manual
• Long March-3B（LM-3B） China Academy of Launch Vehicle Technology - LM-3B product page