Delta Cryogenic Second Stage
 A 4-meter DCSS from a Delta IV Medium | |
| Manufacturer | Boeing IDS United Launch Alliance Mitsubishi Heavy Industries (Original Delta III design and manufacturing) JAXA/NASDA (H-IIA/DCSS upper stage design, original version) |
|---|---|
| Country of origin | United States Japan (Delta III, original) |
| Used on | Delta III Delta IV SLS Block I |
| Launch history | |
| Status | Active |
| Total launches | 45 |
| Successes (stage only) | 42 18 Delta IV 4 m 23 Delta IV 5 m |
| Failed | 2 (Delta III) |
| Lower stage failed | 1 (Delta III) |
| First flight | August 27, 1998 |
| Last flight | April 9, 2024 |
| Delta III second stage | |
| Height | 8.8 meters (29 ft) |
| Diameter | 4 meters (13 ft) (LH2 tank) 3.2 meters (10 ft) (LOX tank)[1] |
| Empty mass | 2,480 kilograms (5,470 lb) |
| Gross mass | 19,300 kilograms (42,500 lb) |
| Powered by | 1 RL10B-2 |
| Maximum thrust | 110.1 kilonewtons (24,800 lbf) |
| Specific impulse | 462 seconds (4.53 km/s) |
| Burn time | 700 seconds |
| Propellant | LH2/LOX |
| Delta IV 4-meter stage | |
| Height | 12.2 meters (40 ft) |
| Diameter | 4 meters (13 ft) (LH2 tank) 3.2 meters (10 ft) (LOX tank)[1] |
| Empty mass | 2,850 kilograms (6,280 lb) |
| Gross mass | 24,170 kilograms (53,290 lb) |
| Powered by | 1 RL10B-2 |
| Maximum thrust | 110.1 kilonewtons (24,800 lbf) |
| Specific impulse | 462 seconds (4.53 km/s) |
| Burn time | 850 seconds |
| Propellant | LH2/LOX |
| Delta IV 5-meter stage | |
| Height | 13.7 meters (45 ft) |
| Diameter | 5 meters (16 ft) (LH2 tank) 3.2 meters (10 ft) (LOX tank)[1] |
| Empty mass | 3,490 kilograms (7,690 lb) |
| Gross mass | 30,710 kilograms (67,700 lb) |
| Powered by | 1 RL10B-2 |
| Maximum thrust | 110.1 kilonewtons (24,800 lbf) |
| Specific impulse | 462 seconds (4.53 km/s) |
| Burn time | 1125 seconds |
| Propellant | LH2/LOX |
| Interim Cryogenic Propulsion Stage (SLS Block 1)[2] | |
| Height | 13.7 meters (45 ft) |
| Diameter | 5 meters (16 ft) (LH2 tank) 3.2 meters (10 ft) (LOX tank)[1] |
| Empty mass | 3,800 kilograms (8,400 lb) |
| Gross mass | 32,748 kilograms (72,197 lb) |
| Powered by | 1 RL10B-2 |
| Maximum thrust | 110.1 kilonewtons (24,800 lbf) |
| Specific impulse | 462 seconds (4.53 km/s) |
| Burn time | 1125 seconds |
| Propellant | LH2/LOX |
The Delta Cryogenic Second Stage (DCSS) is a family of cryogenic rocket stages used on the Delta III and Delta IV rockets, and on the Space Launch System Block 1. The stage consists of a cylindrical liquid hydrogen (LH2) tank structurally separated from an oblate spheroid liquid oxygen (LOX) tank. The LH2 tank cylinder carries payload launch loads, while the LOX tank and engine are suspended below within the rocket's inter-stage. The stage is powered by a single Aerojet Rocketdyne-Pratt & Whitney RL10B-2 engine,[3] which features an extendable carbon–carbon nozzle to improve specific impulse.[4]
Delta III
The DCSS first flew on 3 Delta IIIs, failing two out of two times. A booster failed on the maiden flight and the rocket was destroyed by range safety, causing the loss of the DCSS before ignition. On its second flight, the stage tumbled uncontrollably, inserting the payload into a useless orbit. On the third flight, the stage performed the planned burn but fell short of the target orbit due to premature propellant exhaustion. The flight was deemed a failure.[5] An un-flown example is on display outside the Discovery Cube Orange County.[6]
Delta IV
Two different versions were flown, depending on the Delta IV variant. Composite interstages were used to mate the first and second stages together accommodate the different configurations.[4] For the Delta IV-M, a tapering interstage that narrows down in diameter from 5 meters to 4 meters was used on the 4-meter DCSS, while a cylindrical interstage was used on the 5-meter DCSS (for Delta IV Heavy).[4]
After the retirement of the Delta IV-M and Delta IV-M+ rockets, the DCSS was used solely on the Delta IV Heavy in its 5-meter variation. The Delta IV Heavy retired after its last launch on April 9, 2024.[7]
Interim Cryogenic Propulsion Stage
The Interim Cryogenic Propulsion Stage, a minimally modified 5-meter DCSS, is used as the upper stage of the Space Launch System Block 1. The ICPS for Artemis I was mated to the SLS launch stack on July 6, 2021.[8][9] Artemis 1 was launched on November 16, 2022, at 06:47:44 UTC (01:47:44 EST).[10]The ICPS performed as expected. The ICPS will be used for Artemis II and Artemis III before being retired in favor of the in-development Exploration Upper Stage for Artemis 4.[11] It is powered by one Aerojet Rocketdyne RL10 engine and generates 24,750 lbs. of maximum thrust.
References
- ^ a b c d "Delta IV Launch Services User's Guide" (PDF). United Launch Alliance. Retrieved April 12, 2024.
- ^ Braeunig, Robert. "SPECIFICATIONS & TECHNICAL DATA: Space Launch System". Retrieved January 19, 2024.
- ^ Robert A. Braeunig (2 November 2009). "Space Launchers—Delta". Rocket and Space Technology. Retrieved 26 January 2012.
- ^ a b c "Delta IV Payload Planners Guide" (PDF). United Launch Alliance. September 2007. pp. 1–5 to 1–6. Archived from the original (PDF) on 22 July 2011.
- ^ "Delta 8930". astronautix.com. Retrieved 16 September 2022.
- ^ Dave Nordling (October 8, 2017). "Discovery Cube – Orange County". Reaction Research Society. Retrieved May 15, 2023.
- ^ published, Robert Z. Pearlman (2024-04-09). "'Heavy' history: ULA launches final Delta rocket after 64 years (video, photos)". Space.com. Retrieved 2024-04-17.
- ^ Chris Bergin (4 October 2011). "SLS trades lean towards opening with four RS-25s on the core stage". NASASpaceflight.com. Retrieved 26 January 2012.
- ^ Rosenberg, Zach. "Delta second stage chosen as SLS interim". Flight International, May 8, 2012.
- ^ "Artemis 1". NASA. Archived from the original on December 19, 2022. Retrieved November 17, 2022.
- ^ Bergin, Chris (2020-02-03). "Upper Stage RL10s arrive at Stennis for upcoming SLS launches". NASASpaceFlight.com. Retrieved 2022-08-17.