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Delta II

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Delta II
retired expendable launch system in the Delta rocket family
A Delta II rocket takes off from Cape Canaveral
Has useLaunch vehicle
ManufacturerUnited Launch Alliance
Country of originUnited States
Cost per launchUS$51 million in 1987 (7920-10 mod.)[1]
Height38.2–39 m (125–128 ft)
Diameter2.44 m (8 ft 0 in)
Mass151,700–231,870 kg (334,440–511,190 lb)
Stages2 or 3
Payload to LEO
Mass2,700–6,100 kg (6,000–13,400 lb)
Payload to GTO
Mass900–2,170 kg (1,980–4,780 lb)
Payload to HCO
Mass1,000 kg (2,200 lb)
Launch history
Launch sitesCape Canaveral SLC-17
Vandenberg AFB SLC-2W
Total launches156
Delta 6000: 17
Delta 7000: 132
Delta 7000H: 6
Delta 6000: 17
Delta 7000: 130
Delta 7000H: 6
Failure(s)1 (Delta 7000)
Partial failure(s)1 (Delta 7000)
First flight
Last flight
  • Delta 6000: 24 July 1992 (Geotail)
  • Delta 7000: 15 September 2018 (ICESat-2)
  • Delta 7000H: 10 September 2011 (GRAIL)
Boosters (6000 Series) – Castor 4A
No. boosters9
Powered bySolid
Maximum thrust478 kN (107,000 lbf)
Specific impulse266 s (2.61 km/s)
Burn time56 s
Boosters (7000 Series) – GEM 40
No. boosters3, 4, or 9
Powered bySolid
Maximum thrust492.9 kN (110,800 lbf)
Specific impulse274 s (2.69 km/s)
Burn time64 s
Boosters (7000 Heavy) – GEM 46
No. boosters9
Powered bySolid
Maximum thrust628.3 kN (141,200 lbf)
Specific impulse278 s (2.73 km/s)
Burn time75 s
First stage – Thor/Delta XLT(-C)
Powered by1 RS-27 (6000 series) or RS-27A (7000 series)[2]
Maximum thrust1,054 kN (237,000 lbf)
Specific impulse302 s (2.96 km/s)
Burn time265 s
Second stage – Delta K
Powered by1 AJ10-118K
Maximum thrust43.6 kN (9,800 lbf)
Specific impulse319 s (3.13 km/s)
Burn time431 s
PropellantTemplate:N2O4 / Aerozine 50
Third stage – PAM-D (optional)
Powered byStar 48B
Maximum thrust66 kN (15,000 lbf)
Specific impulse286 s (2.80 km/s)
Burn time87 s

Delta II was a rocket used to launch various projects into space. The Delta series of rockets were first designed and made by McDonnell Douglas. This company joined with Boeing in 1997. Delta II rockets had been made since 2006 by United Launch Alliance, which is a joint company owned by Boeing and Lockheed Martin to supply launch rockets to the US government. Boeing Launch Services supplied Delta II rockets to private companies.

The Delta II rockets were based on the Thor rockets built in the 1950's. These were used to carry Inter Continental Ballistic Missiles. The first Thor was launched on January 26, 1957.[3] The Delta II rocket was first launched on 14 February 1989.[3] The rocket was developed after the explosion of the Space Shuttle Challenger in 1986. The US Air Force needed another way to launch its GPS satellites.[3] As of 2018, there had been 156 Delta II launches from both Cape Canaveral Air Force Station and the Vandenberg Air Force Base.[3] Only two launches were unsuccessful. On 5 August 1995, a rocket motor failure meant the Koreasat 1 was put into a lower orbit. On 17 January 1997, Delta 241 carrying the GPS IIR-1 exploded 13 seconds after taking off.[3]

The last time the Delta II took off on 15 September 2018, when she carried the ICESat-2 satellite.[4][5][6]

References[change | change source]

  1. "Delta II 7920H-10 - SPACEFLIGHT101". Archived from the original on 14 July 2014. Retrieved 1 July 2014.
  2. "Boeing: Integrated Defense Systems - Delta - Delta II Launch Vehicle Family". Archived from the original on 3 November 2006. Retrieved 3 November 2006.
  3. 3.0 3.1 3.2 3.3 3.4 Graham, William (28 October 2011). "Delta II successfully launches NPP satellite on behalf of NASA and NOAA". nasaspaceflight.com. Retrieved 6 November 2012.
  4. Graham, William (2 July 2014). "ULA Delta II successfully lofts OCO-2 to orbit". NASASpaceflight.com. Archived from the original on 14 July 2014. Retrieved 23 July 2014.
  5. "NASA Selects Launch Services Contract For Three Missions". MarketWatch. 16 July 2012. Archived from the original on 29 January 2013. Retrieved 16 July 2012.
  6. "NASA Selects Launch Services for ICESat-2 Mission". NASA Kennedy Space Center. 22 February 2013. Archived from the original on 8 July 2013. Retrieved 15 March 2013.

Related pages[change | change source]