Spirit AeroSystems Inc. on Thursday announced that it has partnered with Aerion Corp. for work on the companyâs supersonic AS2 business jet. The company said in a press release that it has partnered with Nevada-based Aerion to work on the preliminary design of the aircraftâs forward, pressurized fuselage. Financial terms of the agreement were not disclosed. âJoining a project team this early allows us to apply our technical expertise and commercial best practices to make the positive impact,â Tom Gentile, CEO of Spirit (NYSE: SPR), said in a statement. âWe are proud to partner with Spirit AeroSystems.