Aerojet Rocketdyne

AR1

The AR1 is a 2,200-kilonewton-class (500,000 lbf) thrust RP-1/LOX advanced oxidizer-rich staged combustion cycle engine project.^[7] Aerojet Rocketdyne proposed in 2014 to "lobby the government to fund an all-new, U.S.-sourced rocket propulsion system." In June 2014, Aerojet's initially projected it would cost under US$25 million per pair of engines, not including the up to US$1 billion estimated development cost to be funded by the government.^[8][9] Later in 2014, the US Congress passed a law requiring the US Air Force to "develop a new propulsion system by 2019 to replace the RD-180 engine" that powers Atlas V used by United Launch Alliance (ULA).^[10] Dynetics is a key partner in development of the AR1 engine. Under a joint venture agreement, Dynetics is to supply elements of the engine's main propulsion system, the ignition system, and ground support equipment, along with analysis support to critical engine designs.^[11]

ULA announced in early February 2015 that they are considering undertaking domestic production of the Russian RD-180 engine at its Decatur, Alabama rocket manufacturing facility. The US-manufactured engines would be used only for government civil (NASA) or commercial launches, and would not be used for US military launches. ULA CEO Tory Bruno also indicated that ULA is considering the AR1 option, along with the US manufacture of the RD-180 by ULA under license as backup options to the primary option ULA is pursuing for the Atlas V successor with the Blue Origin BE-4 methane/LOX engine.^[12]

The AR1 engine has the advantage of matching the fuel configuration of the Atlas V launch vehicle. However, it is disadvantaged by being much earlier in the development process for a new rocket engine to replace the high performing RD-180 engine.^[13][14][15] In February 2015, the USAF released the results of its analysis of the project to build a new US government-funded engine in five years, and said that the "2019 deadline was too aggressive given that it would likely take six to eight years to develop an alternate U.S.-built engine, plus another year or two to integrate the new engine with existing rockets."^[10] Aerojet Rocketdyne has stated a commitment to delivering the AR1 in 2019.^[16]

In September 2015, AJR made an offer to buy ULA for US$2 billion. Shortly thereafter however, ULA and Blue Origin announced a joint agreement to expand production capabilities in order to manufacture the BE-4 rocket engine currently in development and test. ULA also reconfirmed that the decision on using the BE-4 vs. AJR AR1 for the new Vulcan rocket would not be made until late 2016, with maiden flight of Vulcan continuing to be planned for no earlier than 2019.^[17]

The U.S. Air Force awarded a $115 million contract to Aerojet Rocketdyne for development of the AR1 engine to be completed in 2019. Contract options could increase government funding up to $501 million.^[18][19][20] Aerojet had received US$228 million in funding for AR1 through June 2017.^[21] In April 2017, Aerojet announced that the engine would be built in a new factory planned to be built in Huntsville, Alabama.^[22] Aerojet completed the AR1's Critical Design Review (CDR) in May 2017.^[23]

In 2016, the USAF originally awarded AJR a contract for up to US$536 million to advance development of the AR1 engine.^[24] In February 2018, Aerojet began negotiating with the U.S. Air Force to reduce the company's financial contribution to the development of the AR1 engine to one-sixth of the costs (from a previously agreed one-third). Up to that date, AJR had "spent US$86.1 million on AR1 research and development, out of total costs incurred to date of US$236.6 million."^[25] By June 2018, the USAF had renegotiated the agreement with AJR and decreased the Air Force contribution—5/6ths of the total cost—to US$295 million. AJR is adding no additional private funds into the engine development effort after early 2018.^[26]

AR-22

The AR-22 is an engine in development in 2017 for the XS-1 spacecraft, based on the Space Shuttle Main Engine and utilizing parts remaining in Aerojet Rocketdyne and NASA inventories from earlier versions of the SSME. Two of the engines will be built for the spaceplane.^[27]

X3 ion thruster

On 13 October 2017, it was reported that Aerojet Rocketdyne completed a keystone demonstration on a new X3 ion thruster, which is a central part of the XR-100 system for the NextSTEP program.^[28][29] The X3 ion thruster was designed by the University of Michigan^[30] and is being developed in partnership with the University of Michigan, NASA, and the Air Force. The X3 is a Hall-effect thruster operating at over 100 kW of power. During the demonstration, it broke records for the maximum power output, thrust and operating current achieved by a Hall thruster to date.^[28] It operated at a range of power from 5 kW to 102 kW, with electrical current of up to 260 amperes. It generated 5.4 Newtons of thrust, "which is the highest level of thrust achieved by any plasma thruster to date."^[28][31] A novelty in its design is that it incorporates three plasma channels, each a few centimeters deep, nested around one another in concentric rings.^[29] The system is 227 kg (500 lb) and almost one meter in diameter.^[28]