Online Detection and Avoidance of Helicopter TGT Limits

Turboshaft engines of rotary-wing aircraft impose limitations on the flight envelope via Turbine Gas Temperature (TGT). Pilots are required to react on possible violations by monitoring TGT limits. For a fly-by-wire system, avoidance of the TGT limit could be accomplished using tactile cues and advanced envelope protection algorithms. In this paper, a neural-network-based adaptive limit detection algorithm is used to estimate approaching TGT violations and the corresponding control limits on the collective control. Collective limits are then used for avoidance of the TGT limit. High fidelity helicopter and engine models are used to show that TGT violations can be estimated with sufficient lead time to warn the pilot using tactile cues.


Online Dynamic Trim and Control Limit Estimation
Yavrucuk, İlkay (American Institute of Aeronautics and Astronautics (AIAA), 2012-9)
The online estimation of a maneuvering steady-state condition of an aircraft, called the dynamic trim, is used to estimate the allowable control travel during flight, a key information in pilot cueing for envelope limit protection. In this paper a new methodology is presented where adaptive models are used to estimate online local dynamic trim conditions, while requiring very limited a priori vehicle information. Adaptive neural networks are employed to enable online learning. The models are used to estimat...
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The main objective of this study is to make a numerical model of direct connected ramjet test facility which is used for ground tests of supersonic air breathing propulsion systems. Conceptual design of a direct connected ramjet test facility is performed. 1 dimensional transient numerical model is made according to this conceptual design. Numerical model is made by using 1 dimensional computational fluid dynamic code FLOWNEX. Validation of the numerical model is performed by comparison of test data. After ...
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The aerodynamics of insects flying at low Reynolds numbers is considered for Micro Air Vehicles (MAV) designs. The aim of this study is to analyze different flapping wing models and to predict generated forces and vortices around the wings. The analyses are significant for understanding properties of flying animals like birds, insects and for improving MAVs more. For three insect species (namely, bumblebee, hawkmoth, and hummingbird), three dimensional (3D) wing models are numerically analyzed at different ...
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In a companion liquid rocket engine development project, due to the overall weight constraint of the propulsion system, a cavitating venturi is selected to control the liquid fuel and liquid oxidizer mass flow rates. Two cavitating venturis, one for the fuel and the other for the oxidizer, are designed to deliver the desired mass flow rates for a specified operating inlet pressure, temperature, and inlet cross-sectional area. The converging and diverging angles of the venturis are selected from the literatu...
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Pınar, Erdem Emre; Baker, Derek Keıth; Uzgören, Eray; Department of Mechanical Engineering (2013)
In this thesis, energy optimal route of an unmanned solar powered air vehicle is obtained for the given mission constraints in order to sustain the maximum energy balance. The mission scenario and the constraints of the solar powered UAV are defined. Equations of motion are obtained for the UAV with respect to the chosen structural properties and aerodynamic parameters to achieve the given mission. Energy income and loss equations that state the energy balance, up to the position of the UAV inside the atmos...
Citation Formats
İ. Yavrucuk, “Online Detection and Avoidance of Helicopter TGT Limits,” presented at the 69th American Helicopter Society Forum, (21 - 23 May 2013), Phoenix, AZ, USA, 2013, Accessed: 00, 2021. [Online]. Available: