This paper describes how the NASA Orion program is delivering the flight test spacecraft using affordable and flexible manufacturing and test operations in an evolving and changing development environment. The Orion program successfully completed the Exploration Flight Test 1 (EFT-1) in 2014 and is currently developing the spacecraft to meet the test objectives of an orbital mission to the moon and return to earth in 2018 called Exploration Mission 1 (EM-1). These flight test spacecraft are evolving in design maturity and complexity requiring significant changes in the build and test operations for each vehicle. Meeting these challenging objectives affordably is enabled by utilizing the flexibility of the Neil Armstrong Operations and Checkout (O&C) Facility based on lean operational concepts and innovative production and test approaches by the Orion team at the Kennedy Space Center. The first flight test vehicle, EFT-1, was built and tested in 27 months as the first Orion spacecraft manufactured and tested using the O&C facility. To meet this schedule challenge, additional assembly of electrical harnesses, Multi-Layered Insulation (MLI) blankets, and Thermal Protection System (TPS) tile bonding were added to the floor operations to improve the integration of these systems into the spacecraft. Flexible and portable ground support equipment was developed for use in the O&C facility as well as for other locations across the country reducing program costs. Additional vehicle testing was added to the test operations for structural static and dynamic testing avoiding transportation cost and time to transport the spacecraft to dedicated test facilities. The second flight test vehicle processed in the O&C is the EM-1, which will have additional flight systems installed to fly to the moon and return. Producibility design improvements have been incorporated to improve vehicle layouts for space allocations, improve structural designs, improve heat shield and back shell configurations, and improve the clean room operations using a reconfigurable weld station for tube welding. Additional systems environmental testing has been added to the O&C operations to include low cost portable acoustics and thermal chamber test capabilities. As the Orion program evolves with flight rate changes, launch vehicle changes, test operations maturity, and design changes to the vehicle, the flexibility of the manufacturing and test operations accommodates these impacts with minimum cost and schedule impacts to the flight test program.