sentences:  Since the actual upper-stage hardware could not be produced in time for the flight test, the upper-stage mass simulator allowed the booster to fly approximately the same trajectory through the first stage of flight.The USS and the CM/LAS mass simulators launched by the Ares I-X were not recovered and fell into the Atlantic Ocean.The first stage, including the fifth segment mass simulator, was recovered to retrieve flight data recorders and reusable equipment.