Close up of the first General Electric GEnx engine installed on Boeing 787-8 Dreamliner ZA005. The GEnx engine is the second of two engine types offered to customers on the 787 Dreamliner. The four airplanes already in the flight test fleet are powered by Rolls-Royce Trent 1000 engines. ZA005 will be used to test the General Electric engine package and demonstrate that the changes made with the new engine do not change the airplane’s handling characteristics. The GEnx engine is the second of two engine types offered to customers on the 787 Dreamliner. The four airplanes already in the flight test fleet are powered by Rolls-Royce Trent 1000 engines. ZA005 will be used to test the General Electric engine package and demonstrate that the changes made with the new engine do not change the airplane’s handling characteristics.