After Lufthansa's order of 30 aircraft, the new project really began expanding, although they still had to fight with many problems. They had problems with the 3rd party pieces but also still with the bad vending. Finally, 2013, the first CS100 could take-off and a few months later, the 2nd  aircraft reached the sky. With the fifth prototype, Bombardier presented the first aircraft which could fly commercial flights. That means it had the colors of SWISS and inside, the configuration was completed. With this aircraft and the first prototype of the bigger brother, Bombardier flew to the Paris Air Show in 2015 and officially presented the aircraft the first time. Bombardier also went to Zurich and presented the CS100 to SWISS and the press. In 2016 they also done some test flights out of Zurich to prove the usability for European traffic. Then, on the 30th  October 2016, the first aircraft of the CSeries program changed the owner: HB-JBA owned now to SWISS. Half a month later, SWISS flew the first commercial flight with it to Paris. Later that year, also the first CS300 went into regular flight operations for Air Baltic.  But Bombardier still had one problem: There were too few customers and orders. So Bombardier went to Delta Air Lines and made them an unbeatable offer, so Delta made the biggest order in the history of the CSeries and ordered 75 CS100. Unfortunately, this help came too late. After some financial support from Canada and Québec, Bombardier still made a too big discount for Delta and all the other customers, so the whole program was in deficit. For this reason, Bombardier searched a purchaser and had negotiations with Airbus and Embraer. But first, both said no. Later, Airbus bought 50.1% of the newly founded "C Series Aircraft Limited Partnership" (CSALP). The rest of the cooperation went over to Bombardier (31%) and the state of Québec (19%). So from October 2017, the CSeries program isn't anymore a Bombardier project, it is now in the hands of Airbus. And to seal the change of the owner, Airbus also changed the name of the aircraft: CS100 to A220-100 and CS300 to A220-300. A new era of the CSeries began.