Delta II

A Delta II launch vehicle launches from Cape Canaveral carrying the Dawn spacecraft.
Function	Launch vehicle
Manufacturer	United Launch Alliance
Country of origin	United States
Cost per launch	US$51 million in 1987 (7920-10 model)[1] US$137 million in 2018 before retirement [2]
Size
Height	38.9 m (128 ft)[3]
Diameter	2.44 m (8 ft 0 in)
Mass	152,000–286,000 kg (335,000–631,000 lb)[3]
Stages	2 or 3
Capacity
Payload to Low Earth orbit
Mass	2,800–6,140 kg (6,170–13,540 lb)[3]
Payload to Geostationary transfer orbit
Mass	1,140–2,190 kg (2,510–4,830 lb)[3]
Payload to Heliocentric orbit
Mass	806–1,519 kg (1,777–3,349 lb)[3]
Launch history
Status	Retired
Launch sites	Cape Canaveral, SLC-17 Vandenberg Air Force Base, SLC-2W
Total launches	155 Delta 6000: 17 Delta 7000: 132 Delta 7000H: 6
Success(es)	153 Delta 6000: 17 Delta 7000: 130 Delta 7000H: 6
Failure(s)	1 (Delta 7000)
Partial failure(s)	1 (Delta 7000)
First flight	Delta 6000: 14 February 1989 (USA-35) Delta 7000: 26 November 1990 (USA-66) Delta 7000H: 8 July 2003 (Opportunity rover)
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. boosters	9
Powered by	Solid
Maximum thrust	478 kN (107,000 lbf)
Specific impulse	266 s (2.61 km/s)
Burn time	56 seconds
Boosters (7000 Series) – GEM 40
No. boosters	3, 4, or 9
Powered by	Solid
Maximum thrust	492.9 kN (110,800 lbf)
Specific impulse	274 s (2.69 km/s)
Burn time	64 seconds
Boosters (7000 Heavy) – GEM 46
No. boosters	9
Powered by	Solid
Maximum thrust	628.3 kN (141,200 lbf)
Specific impulse	278 s (2.73 km/s)
Burn time	76 seconds or 178.03 seconds after lift off
First stage – Thor/Delta XLT(-C)
Powered by	1 RS-27 (6000 series) or RS-27A (7000 series)[4]
Maximum thrust	1,054 kN (237,000 lbf)
Specific impulse	302 s (2.96 km/s)
Burn time	260.5 seconds
Propellant	RP-1 / LOX
Second stage – Delta K
Powered by	1 AJ10-118K
Maximum thrust	43.6 kN (9,800 lbf)
Specific impulse	319 s (3.13 km/s)
Burn time	431 seconds
Propellant	N2O4 / Aerozine 50
Third stage – PAM-D (optional)
Powered by	Star 48B
Maximum thrust	66 kN (15,000 lbf)
Specific impulse	286 s (2.80 km/s)
Burn time	87 seconds
[edit on Wikidata]

Delta II was an expendable launch system, originally designed and built by McDonnell Douglas. Delta II was part of the Delta rocket family and entered service in 1989. Delta II vehicles included the Delta 6000, and the two later Delta 7000 variants ("Lite" and "Heavy"). The rocket flew its final mission ICESat-2 on 15 September 2018, earning the launch vehicle a streak of 100 successful missions in a row, with the last failure being GPS IIR-1 in 1997.^[3]

The Delta II series was developed after the 1986 Challenger accident and consisted of the Delta 6000-series and 7000-series, with two variants (Lite and Heavy) of the latter.

The Delta 6000-series introduced the Extra Extended Long Tank first stage, which was 12 feet longer, and the Castor 4A boosters. Six SRBs ignited at takeoff and three ignited in the air.^{[citation needed]}

The Delta 7000-series introduced the RS-27A main engine, which was modified for efficiency at high altitude at some cost to low-altitude performance, and the lighter and more powerful GEM-40 solid boosters from Hercules. The Delta II Med-Lite was a 7000-series with no third stage and fewer strap-ons (often three, sometimes four) that was usually used for small NASA missions. The Delta II Heavy was a Delta II 792X with the enlarged GEM-46 boosters from Delta III.^{[citation needed]}