Flight Test Techniques for Quantifying Pitch Rate and Angle of Attack Rate Dependencies

This paper presents an aerodynamic characteristic study in longitudinal direction of UiTM Blended Wing Body-Unmanned Aerial Vehicle Prototype (BWB-UAV Prototype) equipped with horizontal stabilizers. Flight tests have been conducted and as the result, BWB experienced overturning condition at certain angle of attack. Horizontal stabilizer was added at different location and size to overcome the issue during the flight test. Therefore, Computational Fluid Dynamics (CFD) analysis is performed at different configuration of horizontal stabilizer using Spalart - Allmaras as a turbulence model. CFD simulation of the aircraft is conducted at Mach number 0.06 or v = 20 m/s at various angle of attack, α. The data of lift coefficient (CL), drag coefficient (CD), and pitching moment coefficient (CM) is obtained from the simulations. The data is represented in curves against angle of attack to measure the performance of BWB prototype with horizontal stabilizer. From the simulation, configuration with far distance and large horizontal stabilizer gives steeper negative pitching moment slope indicating better static stability of the aircraft.

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Methods for selecting the supporting curve for the model of hysteresis loop

ITM Web of Conferences ◽

10.1051/itmconf/20181801003 ◽

2018 ◽

Vol 18 ◽

pp. 01003

Author(s):

O.N. Korsun ◽

A.V. Stulovskii

Keyword(s):

Hysteresis Loop ◽

Test Data ◽

Flow Separation ◽

Physical Interpretation ◽

Lift Coefficient ◽

Angle Of Attack ◽

Flight Test ◽

Separation Point ◽

Aerodynamic Coefficients

The article deals with a model describing the dependence of aerodynamic coefficients on the angle of attack for post-stall conditions. This paper also discusses the choice of parameters for the calculating the lift coefficient in such cases. In addition, it also considers some methods used to choose the shape of a supporting curve. The article also provides arguments concerning the physical interpretation of the coordinate of flow separation point in the implementation of the model. The examples of processing the flight test data are presented.

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F-35 High Angle of Attack Flight Control Development and Flight Test Results

AIAA Aviation 2019 Forum ◽

10.2514/6.2019-3227 ◽

2019 ◽

Author(s):

Dan Canin

Keyword(s):

Flight Control ◽

Angle Of Attack ◽

Flight Test ◽

Test Results ◽

High Angle ◽

High Angle Of Attack

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Angle of Attack Sensor for Small Fixed-Wing Unmanned Aerial Vehicles

Proceedings ◽

10.3390/proceedings2019039019 ◽

2020 ◽

Vol 39 (1) ◽

pp. 19

Author(s):

Wanngoen ◽

Saetunand ◽

Saengphet ◽

Tantrairatn

Keyword(s):

Unmanned Aerial Vehicles ◽

Flow Direction ◽

Air Flow ◽

Angle Of Attack ◽

Flight Test ◽

Unmanned Aircraft ◽

Aerodynamic Parameter ◽

Aerial Vehicles ◽

Flow Changes ◽

Good Agreement

The angle of attack (AOA) is an important parameter for estimating aerodynamic parameter the performance and stability of aircraft. Currently, AOA sensors are used in general aircraft. However, there is no a reasonable-price AOA sensor that is compatible to a small fixed-wing unmanned aerial vehicles (UAVs). This research aims to designs and constructs angle of attract (AOA) sensor for small fixed-wing unmanned aircraft. Mechanism Design, which is similar to aerodynamic wheatear vane, can operate in airspeed 10–30 m/s. The direction of airfoil aligns with the air flow direction. When the AOA of the UAV changes, the air flow changes the direction, resulting in the change of airfoil direction. The high-resolution rotary encoder, that was used to measure the angle of the airfoil, was installed with the fin airfoil. For experiment, the accuracy of the AOA sensor was validated by comparing the angles obtained from the encoder with the standard rotary table in static and wind tunnel. Finally, the AOA sensor, which was attached on aircraft, was verified and recorded in flight test. As the results of the measurement, the airfoil angles detected by the encoder were in good agreement with the standard angles.

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