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This study deals with a simulation tool which enables evaluation of cockpit procedures by activating a crew behavioral model and dynamic environment of aircraft operations. This crew behavioral model employs both physical and cognitive characteristics of human crew members and the tool presents the sequence of their behavior in a form of three dimensional animation. In order to expand the area of application of this tool toward more specific design issues, functions of behavior in non-normal situations were developed. Applicability of this reinforced simulation tool was demonstrated by applying it to examinations of procedures of a research aircraft and identification of test cases of piloted flight simulation. The results of the behavioral simulation were compared with the results of piloted flight simulation.

The Upper Surface Blowing STOL experimental aircraft ASKA, was developed and flight tested by the National Aerospace Laboratory of Japan. The ASKA operated well on the backside of the drag curve, and because of this flight path control was accomplished with the throttle lever (thrust) during approach and landing. To compensate for the sluggish flight path response caused by the thrust response lag, the flight path control law put in stability and control augmentation system. Flight tests were conducted to evaluate flight path and airspeed response characteristics. This paper describes ASKA's flight path and airspeed response characteristics, as well as construction of the flight path control system.

The Japanese Quiet Short Take Off and Landing experimental aircraft named ASKA was developed and flight tested during 1977 till 1989. The control system hard and software were examined by the functional mock-up with using the actual hardware. The small longitudinal limit cycle was observed in the closed loop test when the Pitch Control Wheel Steering software was on in the mock-up testing. In this paper, first, the method to analyze and to expect the limit cycle based on the describing function was shown. The limit cycle was induced due to the nonlinearities in the automatic control mechanism. The nonlinearities in the hardware were examined to make the model to simulate the system on the computer. The method was shown effective to predict the limit cycle in the mock-up. Second, with using the flight measured dynamics, the limit cycle was concluded as on border line between existing and not, which coincides with the actual flight result.

Control system functional mock-up tests were conducted with ASKA, a quiet short take-off and landing aircraft. Simulation was effectively simplified by omitting the control system right half side and shortening the system's straight sections. Characteristic differences were compensated for by changing cable tension, with simulation “fidelity” being sufficient to check each area of concern. All test measurements were precisely taken, and a “filtering sampler,” an anti-aliasing device/technique, was newly designed and used for digital data acquisition. The mock-up tests significantly contributed to the control system development by providing data to refine the stability and control augmentation system, by enabling accomplishment of system and component clearance tests, by determining unexpected phenomena, and by allowing performance of experimental studies on possible critical problems.

The four engined Upper Surface Blowing (USB) STOL research aircraft ASKA was developed by National Aerospace Laboratory of Japan and has been in the flight test phase to provide various kinds of flight data. The position error in airspeed and angle of attack is discussed, and the low speed performance demonstrated in the flight test is provided by the figures of lift/drag coefficient curves and V-Gamma plot. Several indications of powered lift and dynamic stability derivatives obtained from the V-Gamma plot are discussed. The flight measured pitching moment shows the distinctive features such as pitch up tendency. The wing-body pitching moment and the downwash angle are analyzed from the flight load measurments of the horizontal tail. The ground effect of the ASKA is also presented quantitatively in this paper.

“ASKA” is a STOL airplane with Upper Surface Blown type (USB) flaps used to perform research on powered lift technology developed by the National Aerospace Laboratory (NAL). ASKA has four high bypass ratio turbofan engines mounted above and forward of the wings, hydraulically actuated flight controls, and the Stability and Control Augmentation System (SCAS). The SCAS is a triple redundant system with three digital computers. In order to develop and evaluate its control laws, flight simulator tests have been conducted for 9 years during the design phase. Four flights have been devoted to evaluate functions of the SCAS and the control laws. The significant features of the control laws are to realize satisfactory flying qualities in the deep backside region at low airspeeds.