Preliminary Test Results for Stability and Control Characteristics of a Generic T-tail Transport Airplane at High Angle of Attack

Abstract

Tests of a generic T-tail transport airplane, in flaps-up configuration, were conducted using two wind tunnels, a water tunnel, and computational fluid dynamics. Static force and moment testing, forced oscillation testing and dye flow visualization test techniques were used. The purpose of the testing was to obtain stability and control characteristics for development of a research flight simulator aerodynamic database. The purpose of that database was for assessment of aerodynamic model fidelity requirements to train airline pilots to recognize and recover from full stall conditions. Preliminary results, at initial stall conditions, include: an unstable stall pitch break, and near-neutral roll damping. Preliminary results, at deep stall conditions, include: a potential static longitudinal trim condition at approximately 35 degrees angle of attack, large aerodynamic asymmetries, and localized unstable dynamic stability.

A Generic T-tail Transport Airplane Simulation for High-Angle-of-Attack Dynamics Modeling Investigations

“…The data for each hysteresis loop were reduced using the single point method. 9 The results only showed a significant relative variation in over a relatively small angle of attack range (14 to 22 degrees). The data were modeled in the simulation as a function of each loop's maximum non-dimensional rate, ̂= ( ̅ )/2 .…”

“…To contribute toward the model fidelity research goals of SE-209, this project has conducted dedicated high-angleof-attack ground testing of a generic T-tail transport (GTT) airplane configuration. 9 The testing used multiple experimental and computational fluid dynamics (CFD) facilities. The test techniques that were used included static and dynamic force and moment testing as well as flow visualization.…”

Efficient Unsteady Model Estimation Using Computational and Experimental Data

“…A portion of the longitudinal force-oscillation data [6] collected for the GTT model at the Boeing Flow-Visualization Water Tunnel (FVWT) in Huntington Beach, CA, was used in this study. The tunnel velocity was set at 1 fps and a sample rate was set at 40 Hz.…”

“…he National Aeronautics and Space Administration (NASA) has completed a number of programs, working with industry, academia, and other government agencies, to improve flight safety and in particular to reduce loss-ofcontrol accidents [1][2][3][4][5]. The NASA Technologies for Airplane State Awareness (TASA), a sub-project of the NASA System Wide Safety (SWS) Program, is continuing this research [6][7]. A number of studies have been completed considering a conventional mid-sized commercial transport with a low horizontal tail; however, the current efforts are focused on models appropriate for T-Tail, aft twin-engine, configurations.…”

“…1 shows a generic sub-scale fighter configuration called the Stability and Control Configuration (SACCON) [11] and Fig. 2 shows the NASA Generic T-Tail (GTT) configuration [6]. The SACCON aerodynamic model, obtained from wind tunnel measurements, is used to create a dynamic simulation with known parameters that allows alternative input designs to be directly evaluated.…”