Safe and Efficient Flight Test Execution through Digital Engineering: High-Fidelity Loads Regression Prediction Generation

Simulating an aircraft model using of high fidelity models of subsystems for its primary and secondary flight control actuators requires measuring or estimating aero-load data acting on flight control surfaces. One solution would be to incorporate the data recorded from flight tests, which is a time-consuming and costly process. This paper proposes another solution based on the validation of an aero-loads estimator or on the hinge moments predictor for fully electrical aircraft simulator benchmark. This estimator is based on an aerodynamic coefficient calculation methodology, inspired by Roskam’s method that uses the geometrical data of the wing and control surfaces airfoils. The hinge moment values are found from two-dimensional lookup tables where the deflections of the control surfaces, aircraft altitude, and aircraft angles of attack are the input vectors of the tables; and the resulting hinge moment coefficients are the output vectors. The resulting hinge moment coefficients of the Convair 880 primary flight control surfaces are compared to those of its recorded flight test data; the results from the new software solution were found to be very accurate. Hinge moment lookup tables are integrated in the Convair 880 high fidelity flight simulation benchmark using mathematical models of energy-efficient Electro-Hydrostatic Actuators (EHA). Autopilot controls are designed for the roll, pitch, attitude and yaw damper motions using Proportional Integral (PI) controller scheduled for different flight conditions. Several different aircraft simulation scenarios are evaluated to demonstrate the efficacy and accuracy of the predicted hinge moment results.

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High-fidelity simulation as a low cost enhancement to flight test

10.2514/6.1996-3520 ◽

1996 ◽

Author(s):

Michael Brunner

Keyword(s):

Low Cost ◽

Flight Test ◽

High Fidelity ◽

High Fidelity Simulation

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Automated Methods to Calibrate a High-Fidelity Thrust Deck to Aid Aeropropulsion Test and Evaluation

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Manufacturing, Materials and Metallurgy; Microturbines and Small Turbomachinery ◽

10.1115/gt2008-50213 ◽

2008 ◽

Cited By ~ 3

Author(s):

Jeffrey F. Monaco ◽

David S. Kidman ◽

Donald J. Malloy ◽

David G. Ward ◽

James F. Gist

Keyword(s):

Parameter Estimation ◽

Steady State ◽

Maximum Likelihood ◽

Modeling And Simulation ◽

Flight Test ◽

Empirical Modeling ◽

High Fidelity ◽

Diverse Range ◽

Test And Evaluation ◽

Ground Test

Modeling and simulation is regularly used to support test and evaluation at the U.S. Air Force aeropropulsion ground and flight test centers. Advanced modeling and simulation tools used to calibrate a high-fidelity thrust program that predicts steady-state and transient operation of a fighter aircraft turbofan engine are discussed in this paper. Maximum likelihood parameter estimation is used to estimate engine-model calibration factors. Empirical modeling techniques are then used to obtain closed-form polynomials characterizing the variations in the calibration factors as functions of engine operating condition. The inferred polynomial relationships are used to constrain the functional form of the calibration factors as part of a final maximum likelihood parameter estimation step. The coefficients of the polynomials are estimated over all ground-test cases simultaneously to minimize the weighted error between ground-test output measurements and thrust-deck predictions. An overview of the modeling and simulation framework is given with examples illustrating how the framework can readily be applied to a diverse range of aeropropulsion test and evaluation tasks. Details of the thrust deck, key variables, and the calibration factors are presented. Calibrated thrust deck predictions are compared with steady-state ground test data; and it is shown how the approach advances the state-of-the-art through methods that are more highly automated and intuitive to the engine analyst. The enhancements that automate the steps to set up a modeling task provide tangible benefits for a variety of test and evaluation applications.

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Aeroacoustic Analysis of a Lift-Offset Coaxial Rotor Using High-Fidelity CFD/CSD Loose Coupling Simulation

Journal of the American Helicopter Society ◽

10.4050/jahs.65.012011 ◽

2020 ◽

Vol 65 (1) ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Zhongqi (Henry) Jia ◽

Seongkyu Lee ◽

Kalki Sharma ◽

Kenneth S. Brentner

Keyword(s):

High Speed ◽

Flight Test ◽

Separation Distance ◽

Flight Speed ◽

Total Power ◽

High Fidelity ◽

Loose Coupling ◽

Coaxial Rotor ◽

Blade Vortex Interaction ◽

Computational Structural Dynamics

This paper presents the aeroacoustic analysis of a lift-offset coaxial rotor in high-speed forward flight using the high-fidelity computational fluid dynamics/computational structural dynamics (CFD/CSD) loose coupling software Helios. Acoustic simulations are performed using the software PSU-WOPWOP at eight microphones positioned below the coaxial rotor. The total power of the three speed cases—100, 150, and 200 kt—is validated against flight-test data and shows good agreement. A series of parametric studies is also conducted to investigate the effect of lift offset, flight speed, and rotor-to-rotor separation distance on acoustics of the coaxial rotor. Strong blade-crossover and self-blade–vortex interaction events of the coaxial rotor, which are major sources of loading noise, are captured via high-fidelity CFD simulations in all speed cases. Highly impulsive acoustic pressure signals are identified in all simulation cases, and the magnitude of mid-frequency sound pressure level (SPL) increases significantly with increasing flight speed and lift offset. The strength of mid-frequency SPL, on the other hand, is reduced significantly as the rotor-to-rotor separation distance increases at 100 kt. However, the higher speed cases do not show a significant reduction in mid-frequency SPL with increasing separation distance.

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Using the Theory of Planned Behavior to Predict Faking in Selection Exercises Varying in Fidelity

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000211 ◽

2018 ◽

Vol 17 (3) ◽

pp. 155-160 ◽

Cited By ~ 3

Author(s):

Daniel Dürr ◽

Ute-Christine Klehe

Keyword(s):

Theory Of Planned Behavior ◽

Planned Behavior ◽

Predictive Validity ◽

Group Discussion ◽

Role Play ◽

Selection Procedure ◽

High Fidelity ◽

Selection Research ◽

Play Group

Abstract. Faking has been a concern in selection research for many years. Many studies have examined faking in questionnaires while far less is known about faking in selection exercises with higher fidelity. This study applies the theory of planned behavior (TPB; Ajzen, 1991 ) to low- (interviews) and high-fidelity (role play, group discussion) exercises, testing whether the TPB predicts reported faking behavior. Data from a mock selection procedure suggests that candidates do report to fake in low- and high-fidelity exercises. Additionally, the TPB showed good predictive validity for faking in a low-fidelity exercise, yet not for faking in high-fidelity exercises.

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