The Orbital Sciences Antares light-to-medium-lift launcher has two modified NK-33 in its first stage, a solid Castor 30-based second stage and an optional solid or hypergolic third stage.[16] The NK-33s are imported from Russia to the United States and modified into Aerojet AJ26s, which involves removing some electrical harnessing, adding U.S. electronics, qualifying it for U.S. propellants, and modifying the steering system.[1]
The Antares rocket was successfully launched from NASA’s Wallops Flight Facility on April 21, 2013. This marked the first successful launch of the NK-33 heritage engines built in early 1970s.[17]
Aerojet has agreed to recondition sufficient NK-33s to serve Orbital’s 16-flight NASA Commercial Resupply Services contract. Beyond that, it has a stockpile of 23 1960s and 1970s era engines. Kuznetsov no longer manufactures the engine, and the lack of a continuing supplier brings into question the long-term viability of Antares. To address this, Orbital has sought to buy RD-180 engines, but maker NPO Energomash’s contract with United Launch Alliance prevents this. Orbital has sued ULA for this, alleging anti-trust violations.[18] Aerojet has offered to work with Kuznetsov to restart production of new NK-33 engines, to assure Orbital of an ongoing supply.[19]
NK-33 and NK-43 are derived from the earlier NK-15 and NK-15V engines, respectively.
The engines are high-pressure, regeneratively cooled staged combustion cycle bipropellant rocket engines, and use oxygen-rich preburners to drive the turbopumps. The turbopumps require subcooled liquid oxygen (LOX) to cool the bearings. These kinds of burners are highly unusual, since their hot, oxygen-rich exhaust tends to attack metal, causing burn-through failures. The United States had not much investigated oxygen-rich combustion technologies until the Integrated Powerhead Demonstrator project in the early 2000s.[2] The Soviets, however, perfected the metallurgy behind this method. The nozzle was constructed from corrugated metal, brazed to an outer and inner lining, giving a simple, light, but strong structure. In addition, since the NK-33 uses subcooled LOX and kerosene, which have similar densities, a single rotating shaft could be used for both turbopumps.[3] Given its longer, heavier nozzle, the NK-43 ratio in vacuum is slightly heavier, with a thrust-to-weight ratio of about 120:1.[4
http://en.wikipedia.org/wiki/NK-33
Local news is saying it’s had an Aerojet engine
“The Soviets, however, perfected the metallurgy behind this method.”
Apparently not.