TM 55-6930-212-10
2-13. MOTION SYSTEM.
2-14. The simulator compartment is mounted on a six-degree-of-freedom (6-DOF) motion system that consists of a
moving platform assembly that is driven and supported from below by six hydraulic actuators. The motion system
provides cues for pitch, roll, yaw, lateral, longitudinal, and vertical movements. To produce realtime dynamic motion
cues, system motion can be either independent (without simultaneous motion in any other degree of freedom) or in any
desired combination.
2-15. Flight simulation includes combined motion that represents changes in aircraft attitude that result directly from use
of flight controls, rough air and wind, changes in aircraft weight and center of gravity that result from fuel consumption,
winching operations, cargo loading, troop displacement, or weapon and ammunition depletion. Motion effects such as
blade imbalance, blades out-of-track, and touchdown impact are also simulated.
2-16. Within the system mechanical limits, the simulator computer programs cause the motion system to respond
realistically to aerodynamic forces and moments. After the computed accelerations have reached zero, all motions
except pitch are imperceptibly washed out to neutral. Pitch attitude is maintained as necessary to simulate sustained
longitudinal acceleration cues. Acceleration onset cues are scaled as large as possible for full use of the range of motion
capabilities of each degree of freedom.
2-17. Depending upon which flight profile is being used, the motion system responds to computer input signals as
discussed in the following paragraphs.
2-18. GROUND CONDITIONS.
2-19. The motion system simulates motion of the aircraft on the apron, taxiway, and runway. The motion is a random,
low-frequency, low-amplitude, multidirectional oscillation with reasonably abrupt application. This includes irregularities
of unimproved or unprepared surfaces, longitudinal effects due to abrupt brake applications, and lateral effects due to
asymmetrical braking.
2-20. TAKEOFF AND LANDING.
2-21. Transition to flight is indicated by abrupt cessation of the random oscillation. The motion system provides the
indications of takeoff and maintains an attitude appropriate for hover. Appropriate motion effects occur as a result of
changes in simulated accelerations during transition to flight.
2-22. Similar effects are reproduced during the landing phase, causing appropriate longitudinal and vertical vibration
effects to occur as in the helicopter. The motion system reproduces the landing impact according to the existing aircraft
attitude and vertical and sideslip velocities. When vertical momentum is too great, landing bounce is simulated.
Pitching and rolling effects of single or multi-gear contact are reproduced, and the magnitude of the bounce depends
upon the current landing weight. The longitudinal effects of brake application are also simulated.
2-23. NORMAL FLIGHT.
2-24. The motion system simulates the complex and repeated cues occurring during all the maneuvers associated with
airwork. Varying degrees of turbulence
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