Delta-K
The Delta-K was an American rocket stage, developed by McDonnell Douglas and Aerojet. It was first used on 27 August 1989 as the second stage for the Delta 4000 series.
 Spent Delta-K stage, photographed in orbit | |
| Manufacturer | United Launch Alliance (formerly Boeing and McDonnell Douglas) |
|---|---|
| Country of origin | United States |
| Used on | Delta 4000 Delta 5000 Delta II |
| General characteristics | |
| Height | 5.9 meters (19 ft)[1] |
| Diameter | 2.4 meters (7.9 ft)[1] |
| Gross mass | 6,954 kilograms (15,331 lb)[1] |
| Propellant mass | 6,004 kilograms (13,237 lb)[2] |
| Engine details | |
| Powered by | 1 AJ10-118K |
| Maximum thrust | 43.63 kilonewtons (9,810 lbf)[1] |
| Specific impulse | 319 seconds (3.13 km/s)[1] |
| Burn time | 431 seconds[1] |
| Propellant | Aerozine 50 / N2O4 |
It continued to serve as the second stage for subsequent variants of the Delta rocket.
It was propelled by a single AJ10-118K rocket engine, fueled by Aerozine 50 and dinitrogen tetroxide,[1] which are hypergolic.
The Delta-K had a long heritage to the first Able stage used in Project Vanguard. The AJ-10 engine was first used in the Able second stage of the Vanguard rocket, as the AJ10-118 configuration. It was initially fueled by nitric acid and UDMH.[3] An AJ10 engine was first fired in flight during the third Vanguard launch, on 17 March 1958, which successfully placed the Vanguard 1 satellite into orbit.
As of 25 May 2008, 138 have been launched,[4] and excluding one which was destroyed by the explosion of a lower stage, none have failed.[4]
The Delta-K was used as the second stage of the Delta II rocket from 1989 to 2018.[4] This second stage was retired at conclusion of the ICESat-2 launch on 15 September 2018.
References
- Delta K Archived 5 May 2008 at the Wayback Machine, Encyclopedia Astronautica, date 30 Jan 1997, accessed 2011-02-01.
- Delta K Archived 14 July 2014 at the Wayback Machine, Spaceflight 101, accessed 2014-07-13.
- Wade, Mark. "AJ10-118". Encyclopedia Astronautica. Archived from the original on 6 July 2008. Retrieved 22 June 2008.
- Forsyth, Kevin S. (10 August 2007). "Vehicle Description and Designations". History of the Delta Launch Vehicle. Retrieved 6 June 2013.