execution; and analysis and reporting. Preparation For both commercial and military aircraft, as well as launch vehicles, flight test preparation begins well before the test vehicle is ready to fly. Initially what needs to be tested must be defined, from which the Flight Test Engineers prepare the test plan, which is essentially certain maneuvers to be flown (or systems to be exercised). Each single test is known as a Test Point. A full certification/qualification flight test program for a new aircraft will require testing for many aircraft systems and in-flight regimes; each is typically documented in a separate test plan. Altogether, a certification flight test program will consist of approximately 10,000 Test Points. The document used to prepare a single test flight for an aircraft is known as a Test Card. This will consist of a description of the Test Points to be flown. The flight test engineer will try to fly similar Test Points from all test plans on the same flights, where practical. This allows the required data to be acquired in the minimum number of flight hours. The software used to control the flight test process is known as Flight Test Management Software, and supports the Flight Test Engineer in planning the test points to be flown as well as generating the required documentation. Once the flight test data requirements are established, the aircraft or launch vehicle is instrumented with a data acquisition system (DAS), or data acquisition unit (DAU) and sensors, to record that data for analysis. Typical instrumentation parameters recorded during a flight test for a large aircraft are: Atmospheric (static) pressure and temperature; Dynamic ("total") pressure and temperature, measured at various positions around the fuselage; Structural loads in the wings and fuselage, including vibration levels; Aircraft attitude, angle of attack, and angle of sideslip; Accelerations in all six degrees of freedom, measured with accelerometers at different positions in the aircraft; Noise levels (interior and exterior); Internal temperature (in cabin and cargo compartments); Aircraft controls deflection (stick/yoke, rudder pedal, and throttle position); Engine performance parameters (pressure and temperature at various stages, thrust, fuel burn rate). Specific calibration instruments, whose behavior has been determined from previous tests, may be brought on board to supplement the aircraft's in-built probes. During the flight, these parameters are then used to compute relevant aircraft performance parameters, such as airspeed, altitude, weight, and center of gravity position. During selected phases of