1986 David and Jay Groen form Groen Brothers Aviation, doing business as GBA,and begin design and construction of a single-seat, open cockpit Gyroplane with the intention of entering the kit-built aircraft market.
1988 The Hawk 0.5, the first Gyroplane to feature a variable pitch rotor system design, flies successfully, indicating conceptual opportunities for enclosed FAA certified Gyroplanes may exist.
1989 Design of the single-seat Hawk I Gyroplane begins.
1990 GBA becomes a fully reporting Public Corporation as Groen Brothers Aviation Inc. (stock symbol GNBA). Construction of the Hawk 1 begins.
1992 The Hawk I Gyroplane makes its maiden flight, with sustained flight testing regimen continuing throughout the year.
1993 Commercial interest in larger four/five place models of the Hawk Gyroplane emerge and design of a two-seat prototype, the H2X Gyroplane, is initiated.
1995 Construction of the Hawk2X is begun.
1997 Flight testing of the H2X Gyroplane, prototype of the four-seat Hawk 4, begins, and later achieves a successful vertical take-off, at a density altitude of 7,000 feet. Design of the Hawk 4 is initiated.Construction of the Hawk 4 prototype begins.
1998 GBA meets with FAA representatives and presents them with the formal application document for type certification of the Hawk 4 Gyroplane.Assembly of the first Hawk 4 Gyroplane begins.
1999 GBA opens a Flight Operations Facility at Buckeye Municipal Airport, 25 miles west of Phoenix, AZ.The first US order for delivery of an FAA Type Certified Hawk 4 Gyroplane is accepted by GBA.The maiden flight of GBA’s first Hawk 4 Gyroplane takes place.The Hawk 4 Gyroplane successfully flies in a crop spraying role, demonstrating its unique advantages over fixed wing and helicopter use.
 2000 GBA signs OEM agreement with Rolls-Royce, to provide the Model 250 series, 420hp turbine engine for GBA’s Hawk 4T, the world’s first turbine-powered Gyroplane.The first flight of the Hawk 4T Gyroplane takes place.
 2001 GBA receives a three-year $50 million equity financing commitment, and announces plans to move their Corporate Headquarters to a new 200,000 square foot manufacturing facility in Glendale, AZ.Modification of an existing fixed wing aircraft, in this case a Cessna 337, into a Gyroplane using GBA’s rotor technology begins. Later in the year this aircraft, called the Revcon 6G Advanced Technology Vehicle, successfully completes its maiden flight, demonstrating the feasibility of such conversions.In the summer of 2001, test flying was proceeding according to plan; the FAA certification program continued to move forward; aircraft orders were in hand; plans were in place for production; and funds seemed assured.The September 11, 2001 terrorist attacks following the earlier collapse of the “Tech Sector” stock market in late 2000 had a devastating impact on aviation companies, including GBA, notably from a cancellation of its anticipated equity funding. This necessitated suspension of the Hawk 4 FAA certification program, the move to Arizona, and a large reduction in the Hawk 4 workforce.
 2002 The Hawk 4 Gyroplane is engaged as an aerial observation platform in the government security plan for the 2002 Winter Olympics and Paralympics. It operates superbly, being mission ready 24/7 and flying sixty-seven observation patrol flights.GBA is selected to participate in the Small Business Homeland Security Exposition, organized by the Senate Small Business Committee. The Hawk 4 was displayed outside the Senate Office Building in Washington D.C. Following the Expo, the Hawk 4 gave demonstration flights to a wide range of US government agencies at Leesburg Airport in Virginia.
 2003 GBA forms a new division, American Autogyro, and with the introduction of the SparrowHawk Gyroplane, becomes the first professional aerospace manufacturer to offer its expertise to the kit-built Gyroplane market. The SparrowHawk is awarded “Best New Design” by the Popular Rotorcraft Association (PRA) at its annual international fly-in.
 2005 The US Department of Defense Advanced Research Projects Agency (DARPA) selects a GBA led team to design a proof of concept high speed, long range, vertical takeoff and landing (VTOL) aircraft for use in search and rescue. Named the “Heliplane,” the goals include VTOL, 1,000 lb useful load, 1,000 nautical mile range, and speeds of to 400mph, over twice the speed of typical helicopters.
2006 Raytheon, this nation’s fifth largest defense contractor, chose GBA to develop both the rotor system and airframe of a DARPA funded Precision Airdrop System (PAS) – a low observable unmanned precision delivery vehicle for resupply of long range recon teams well behind enemy lines.
2007 GBA and Raytheon created a completely new type of aircraft that begins flight as a tube deployed from its delivery aircraft, converts to a glider, and then deploys an autorotating rotor near its destination. A large, scale-model was successfully flown on a military test range in July of 2007.
2008 The SparrowHawk III Quick Build kit is introduced, reducing the build time to less than 300 hours. The FAA evaluates the SparrowHawk III kit and qualifies to be included in the FAA listing of Eligible Amateur-Built Aircraft Kits.GBA successfully completes Phase IA of the Heliplane project, demonstrating by analysis & modeling that a Gyrodyne designed by the GBA team could take off and land vertically, fly in excess of 400mph for at least 1,000 nautical miles, while carrying a 1,000 lb payload.DARPA introduces a new Phase IB and II for the Heliplane project to reduce noise levels and test the rotor in a high-velocity wind tunnel.  Georgia Tech is appointed with GBA as a subcontractor.  Phase IB and Phase II are not completed before funding issues delayed the program.  DARPA does not release funds for this follow-on amid the US financial crisis. As a result, GBA is obliged to sharply reduce its largely DARPA-related work force.In the fall of 2008, GBA arranges new funding from its largest investor, in the form of debt financing that was secured by substantially all of the company’s assets including all of its intellectual property, technologies, and know-how.
2009 With new funding, design begins on more advanced gyroplanes designed for commercial and governmental markets.
2010 Continued engineering development leads to the introduction at Airshow China 2010, of two new all-composite conceptual Gyroplane designs, the 7-place ArrowHawk and tandem 2-place ShadowHawk, the former exhibited as full-scale mock-up.
2012 GBA completes a major financial reorganization of the company by forming a new private company now called Groen Aeronautics Corporation (“GAC”).  Once formed, GAC acquired all the assets of Groen Brothers Aviation Inc. in a transaction equal to more than $210 million. Groen Brothers Aviation Inc. retains a minority share holding in GBA Global.
2015 The Board of Directors passed a resolution to change the company name to Groen Aeronautics Corporation (GAC). The name change was officially recorded on March 10, 2014 with the State of Delaware.