Results 281 to 290 of about 7,767,476 (330)
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Expendable Main Rotor Blade Study
1973Abstract : The report presents results of a design study of expendable main rotor blades for the UH-1H helicopter. The objective of the study was to design blades which could eventually be thrown away after extensive damage rather than be sent back to depot for major overhaul. Unit cost, field repairability, resistance to corrosion and erosion, fatigue
Everett Fournier, John A. Longobardi
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A Model-Scale Wind-Tunnel Study of Main Rotor/Propeller Interference
Proceedings of the Vertical Flight Society 72nd Annual Forum, 2016A model-scale wind tunnel test was conducted to determine propulsive efficiency and relative vibration levels of a tail mounted propeller in the wake of a powered rotor and generic fuselage.
P. Bowles +7 more
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Lynx Main Rotor/Tail Rotor Interactions: Mechanisms and Modelling
Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 1994A flight trial has been conducted by the Defence Research Agency (DRA) Bedford using a Lynx AH Mk5 helicopter fitted with an instrumented tail rotor to collect data on tail rotor aerodynamic performance. The analysis carried out to date has concentrated on the effects of main rotor wake interactions on the tail rotor.
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Modelling the interaction of helicopter main rotor and tail rotor wakes
The Aeronautical Journal, 2007AbstractThe mutual interaction between the main rotor and tail rotor wakes is central to some of the most problematic dynamic phenomena experienced by helicopters. Yet achieving the ability to model the growth and propagation of helicopter rotor wakes with sufficient realism to capture the details of this interaction has been a significant challenge to
T. M. Fletcher, R. E. Brown
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Agility Assessment of Helicopter Main Rotor Design
Proceedings of the Vertical Flight Society 75th Annual Forum, 2019A methodology to implement agility as a tradeoff parameter into multi-disciplinary optimization of a helicopter rotor is proposed. Being a qualitative evaluation measure and having no clear definition, agility is tried to be quantified through utilization of "ease", "speed" and "precision" metrics.
Arda Yucekayali +2 more
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Disk wing to main rotor conversion mechanics
Russian Aeronautics (Iz VUZ), 2016A mathematical model of spatial motion of the disk wing blades converted to the main rotor is presented. The system linkage parameters are defined.
V. V. Pavlov, M. S. Gasilov
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Prediction of Main Rotor, Tail Rotor and Engine Parameters from Flight Tests
49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference <br> 16th AIAA/ASME/AHS Adaptive Structures Conference<br> 10t, 2008In the framework of this research project, the main rotor torque, tail rotor torque, engine torque and main rotor speed of a helicopter in forward flight are estimated by using a state space model from flight tests data. The state space model inputs are nonlinear terms made of combinations of pilot controls and helicopter states.
Michel Nadeau Beaulieu, Ruxandra Botez
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S-92 Main Rotor Blade Life Extension
Proceedings of the Vertical Flight Society 72nd Annual Forum, 2016Rotorcraft structural methodology has traditionally relied upon the use of three sources of conservatism for design and fatigue substantiation of rotorcraft dynamic components: fatigue strength, flight loads, and the aircraft usage spectrum. In contrast to the thousands of engineering hours typically spent quantifying component strength and ...
Raymond Jr. +3 more
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2014 IEEE International Conference on Robotics and Biomimetics (ROBIO 2014), 2014
Rotor flying manipulator (RFM) is a system composed of a rotorcraft and a manipulator. RFM possesses great potential applications and thus has got much concern of the researchers all over the world. However, controller design of the RFM is challenging because of the dynamical coupling between the rotorcraft and the manipulator perplexes the whole ...
Bin Yang +3 more
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Rotor flying manipulator (RFM) is a system composed of a rotorcraft and a manipulator. RFM possesses great potential applications and thus has got much concern of the researchers all over the world. However, controller design of the RFM is challenging because of the dynamical coupling between the rotorcraft and the manipulator perplexes the whole ...
Bin Yang +3 more
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Model 540 Main Rotor Blade Fatigue Test
1976Abstract : The occurrence of catastrophic helicopter accidents due to Bell Model 540-11-250-1 main rotor blade structural failure triggered an Army-wide inspection to determine the condition of the existing 540 blade, and full-scale testing to verify the 1100-hour fatigue life of the Model 540 main rotor blade was conducted at the Eustis Directorate ...
Nicholas J. Calapodas +1 more
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