34th European Forum 2008

(ERF34)

Liverpool, United Kingdom

16-19 September 2008

Volume 1 of 3

ISBN: 978-1-61782-199-8 Printed from e-media with permission by:

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Curran Associates, Inc. 57 Morehouse Lane Red Hook, NY 12571 USA Phone: 845-758-0400 Fax: 845-758-2634 Email: [email protected] Web: www.proceedings.com TABLE OF CONTENTS

VOLUME 1

SESSION 1

PARALLEL SESSION A - SAFETY

The European Safety Team (EHEST): European Partnership for Improving Helicopter Safety ...... 1 M. Masson, M. Van Hijum, A. Healey, J. Vincent, A. Evans

PARALLEL SESSION B - AERODYNAMICS

Rotorcraft Simulations Using a Sliding-grid Approach ...... 47 O. J. Boelens, H. Van Der Ven, J. C. Kok, B. B. Prananta

Higher-Order Accurate Simulations of Blade-Vortex Interaction Using a Discontinuous Galerkin Method on Unstructured Meshes ...... 76 Hee Dong Lee, Oh Joon Kwon

PARALLEL SESSION C – FLIGHT MECHANICS

Numerical Flow Simulations past a Bell 412 Helicopter in Real-Time Hover, Low and High Forward Speed Flight Conditions Using Chimera Grid Technique...... 91 F. Zhang, H. Xu, N. G. Ball, A. W. Gubbels

Chinook Helicopter and Slung Load Coupled Body Dynamic Simulation ...... 141 K. R. Reddy, T. T. Truong, K. J. Bourne, R. A. Stuckey, N. Blacker

SESSION 2

PARALLEL SESSION A – PILOT COUPLING

Nonlinear Rotorcraft Pilot Coupling Analysis and Anti-windup Design ...... 177 Sebastien Kolb, Pierre-Marie Basset

The Strongly Controlled Helicopter...... 210 Linghai Lu, Gareth Padfield, Michael Jump

PARALLEL SESSION B - AERODYNAMICS

BERP IV Aerodynamics, Performance and Flight Envelope...... 245 Kevin Robinson, Alan Brocklehurst

Conservation Issues for RANS-Based Rotor Aeroelastic Simulations ...... 253 Marilyn J. Smith

PARALLEL SESSION C – FLIGHT MECHANICS

Rotary Wing UAV: HIL Tests for a Model-based Feedforward Controller...... 295 Filippo Zanetti, Stefano Colautti, Gian Marco Saggiani, Veronica Rossi

Linear Models for Integrated Flight and Rotor Control...... 333 J. V. R. Prasad, F. E. Olcer, L. N. Sankar, C. He

SESSION 3

PARALLEL SESSION A - ACOUSTICS

Influence of Vortex Models on the Prediction of 2D Airfoil Vortex Interaction ...... 360 S. Loiodice, D. Drikakis, A. Kokkalis

Aeroacoustic Analysis of Main Rotor – Tail Rotor Interaction ...... 370 Timothy M. Fletcher, Karthikeyan Duraisamy, Richard E. Brown

Aeroacoustic Flight Test Data Analysis and Guidelines for Noise-Abatement-Procedure Design and Piloting...... 383 Pierre Spiegel, Frederic Guntzer, Anne Le Duc, Heino Bucholz

PARALLEL SESSION B - AERODYNAMICS

A Two-Grid Overset Method for the Prediction of Isolated Rotor Hover Performance ...... 449 Marvin A. Moulton, Mahendra J. Bhagwat, Francis X. Caradonna

Computational Analysis of Rotor-fuselage Interactional Aerodynamics Using Sliding-plane CFD Method...... 484 R. Steijl, G. Barakos

Blade-vortex Interaction Capture by CFD...... 500 T. Renaud, G. Perez, C. Benoit, G. Jeanfaivre, S. Péron

High Resolution Computation of the Aerodynamics and Acoustics of Blade Vortex Interaction...... 531 Alasdair Thom, Karthikeyan Duraisamy

PARALLEL SESSION C – OPERATIONAL ASPECTS

Helicopter IFR Steep and Curved Approaches Using SBAS Guidance ...... 545 Thomas Lüken, Ernst Groll, Florian Antrack, Bernd Korn

Relevant Aspects of Helicopter-Ship Operations ...... 578 A. Hoencamp, Th. Van Holten, J. V. R. Prasad

Study of a Downwash Caused by a Hovering Rotor in Ground Effect ...... 589 Yasutada Tanabe, Shigeru Saito, Naoko Ooyama, Katsumi Hiraoka

DLR - Onera Common Research Programme for Rotorcraft ...... 600 Blanche Demaret, Klausdieter Pahlke

SESSION 4

PARALLEL SESSION A – ROTORCRAFT-PILOT COUPLINGS

Adverse Rotorcraft-Pilot Coupling: Recent Research Activities in Europe ...... 644 Oliver Dieterich, Joachim Gotz, Binh Dang Vu, Henk Haverdings, Pierangelo Masarati, Marilena Pavel, Michael Jump, Massimo Gennaretti

Adverse Rotorcraft-Pilot Couplings - Prediction and Suppression of Rigid Body RPC Sketches from the Work of Garteur HC-AG16...... 693 Marilena D. Pavel, Binh Dang Vu, Joachim Gotz, Michael Jump, Oliver Dieterich

Adverse Rotorcraft-Pilot Coupling: Test Campaign Development at the University of Liverpool ...... 740 M. Jump, S. Hodge, B. Dang Vu, P. Masarati, G. Quaranta, M. Mattaboni, M. D. Pavel, O. Dieterich

PARALLEL SESSION B - AERODYNAMICS

Computational Analysis of Orthogonal Blade Vortex Interaction ...... 787 Antonio Filippone

Comparison of Finite-State Dynamic Stall Theory with Unsteady Data...... 797 Loren A. Ahaus, David A. Peters

CFD For Tail Rotor Design and Evaluation...... 846 Alan Brocklehurst, René Steijl, George Barakos

PARALLEL SESSION C – STRUCTURES & MATERIALS

Remote Synthesis of Loads on Helicopter Rotating Components using Linear Regression, Load Path and Statistical Analyses...... 867 Xiaobo Yu, Callum Wright, Manfred Heller

VOLUME 2

Robust Optimal Design of Composite Blade Cross Section...... 915 Senthil Murugan, Ranjan Ganguli, Dineshkumar Harursampath

SESSION 5

PARALLEL SESSION A - TESTING

Evaluation of a Steep Curved Rotorcraft IFR Procedure in a Helicopter-ATC Integrated Simulation Test...... 946 Henk Haverdings

The Development of 4-blades New Rotor System for an Unmanned Helicopter with 100kg-class MTOW ...... 987 Deog-Kwan Kim, Keun-Woong Song, Ki-Hoon Chung, Young-Jung Kee, Sung-Ho Kim

PARALLEL SESSION B - AERODYNAMICS

An Approximate Unsteady Aerodynamic Model for Flapped Airfoils Including Improved Drag Predictions...... 1037 Li Liu, Peretz P. Friedmann, Ashwani K. Padthe

High-order Simulation of a Rotor in Forward Flight Using a Four-dimensional Adaptive Flow Solver...... 1082 H. Van Der Ven, O. J. Boelens

Transition Modelling for Rotorcraft CFD...... 1123 Georgios Zografakis, George Barakos, Mark Johnson

PARALLEL SESSION C – FLIGHT MECHANICS

A New Pilot Model for the Assessment of Rotorcraft Handling Qualities ...... 1170 David Reid, Roy Bradley

Demonstration of an Active Sidestick in the DLR Flying Helicopter Simulator (FHS)...... 1174 Max Abildgaard, Wolfgang Von Grunhagen

SESSION 6

PARALLEL SESSION A - DYNAMICS

Helicopter Rotor Load Prediction Using a Geometrically Exact Beam Theory with Multibody Dynamics ...... 1211 S. R. Viswamurthy, Sang Chul Park, Sang Joon Shin

Towards a New Generation of Rotorcraft Comprehensive Analysis: Coupling with CSM and CFD ...... 1254 Biel Ortun, Didier Petot, Khiem-Van Truong, Roger Ohayon

PARALLEL SESSION B - SAFETY

A Numerical-experimental Comparative Analysis of Water Impact Behaviour of Skin Panels Under Different Impact Conditions...... 1287 Edoardo Francesconi, Marco Anghileri, Michele Pittofrati, Luigi-M L Castelletti

Cockpit Image Recording Systems...... 1298 Alan Barclay

Elevated City Helipads: Safety and Design ...... 1330 Alex De Voogt

PARALLEL SESSION C - ACOUSTICS

Prediction of the Effect of Nonlinear Propagation Distortion in Blade Vortex Interaction Noise ...... 1336 Penelope Menounou, Panagiotis Vitsas

Actively Controlled Rotor: Aerodynamic and Acoustic Benefit for the Helicopter Today and Tomorrow...... 1373 A. Altmikus, A. Dummel, R. Heger, D. Schimke

Effect of Computation Parameters on BVI Noise Prediction Using HART II Motion Data ...... 1421 Choongmo Yang, Takashi Aoyama

SESSION 7

PARALLEL SESSION A - DYNAMICS

Coupled CFD/CSD Analysis of a Hovering Rotor Using High Fidelity Unsteady Aerodynamics and a Geometrically Exact Rotor Blade Analysis...... 1461 Hyun-Ku Lee, Sung-Hwan Yoon, Sangjoon Shin, Chongam Kim

Stability Prediction in Tiltrotor Aircraft Including Rotor-Wing Aerodynamic Interaction...... 1476 Taeseong Kim, Sangjoon Shin, Do-Hyung Kim

Vibratory Loads Reduction Analysis of Active Trailing-edge Flap Blades Utilizing Piezoelectric Buckling Actuators ...... 1526 Jae-Sang Park, Sung-Nam Jung, Yung-Hoon Yu

Aeroelastic and Biodynamic Modelling for Stability Analysis of Rotorcraft-Pilot Coupling Phenomena ...... 1572 J. Sarafini, M. Gennaretti, P. Masarati, G. Quaranta, O. Dieterich

PARALLEL SESSION B - SAFETY

Improved Occupant Crash Safety in ...... 1608 Marius Lutzenburger

TCAS II Helicopters - Breaking the Myth...... 1671 Derek Whatling, Mark Prior

A Human Factors Analysis of Rotorcraft Accidents in the U.S...... 1711 Bert Boquet, Sacha Duff

PARALLEL SESSION C – AICRAFT DESIGN

Numerical Analysis of Advanced-innovative Tiltrotor Configurations ...... 1748 Alessandro Scandroglio, Andrea D'Andrea, Stefano Melone

Performance of a Hopping Rotochute...... 1781 E. Beyer, M. Costello

VOLUME 3

Robust Design Optimization of Coaxial Rotor for UAV Application Considering Operational Uncertainty...... 1798 Sangook Jun, Kwanjung Yee, Jaewon Lee, Dong-Ho Lee

The S-61/Sea King with Carson Composite Blades Part 1 ...... 1838 H. C. Curtiss, Frank Carson, Adrian Neve

SESSION 8

PARALLEL SESSION A – AIRCRAFT DESIGN

Analysis and Conceptual Design of a Novel MAV Rotorcraft ...... 1876 Alexander Hall, K. C. Wong, Doug Auld

Exploiting Successfully Demonstrated Rotor Technologies ...... 1917 Simon Ransom

PARALLEL SESSION C – FLIGHT MECHANICS

Validation of the SDRE Controller for Rotorcraft Trajectory Tracking Problems...... 1952 Chang Deok Yang, Jeong Hwan Lee, Chang-Joo Kim

An Investigation of Ship Airwake Phenomena Using Time-accurate CFD and Piloted Helicopter Flight Simulation ...... 1961 James S. Forrest, Steven J. Hodge, Ieuan Owen, Gareth D. Padfield

On the Level of Center of Gravity Modeling Error in Neural Network Based Adaptive Controller Design ...... 1972 Onur Tarimci, Deniz Yilmaz, Ilkay Yavrucuk

SESSION 9

PARALLEL SESSION A - DYNAMICS

SHARCS: Hybrid Control Concept for Vibration Reduction of Helicopters...... 2020 Fatma Demet Ulker, Andrei Mander, Daniel Feszty, Fred Nitzsche

Correlation of Helicopter Rotor Aeroelastic Response with HART-II Wind Tunnel Test Data...... 2053 A. Arun Kumar, S. R. Viswamurthy, Ranjan Ganguli

Combined Action of Variable-Stiffness Devices and Trailing-Edge Flap for Helicopter Hub Loads Reduction...... 2072 M. Gennaretti, M. Molica Colella, J. Serafini, G. Bernardini

PARALLEL SESSION B - AERODYNAMICS

Aerodynamic Investigations on a Helicopter Fuselage with Rotor Hub ...... 2093 F. Vogel, C. Breitsamter, N. A. Adams

PARALLEL SESSION C – FLIGHT MECHANICS

Flight Handling Qualities of a Large Compound Rotorcraft...... 2122 Ben Lawrence, Neil Cameron, Stephen Kendrick

Trajectory Optimization Strategies for the Simulation of the ADS-33 Mission Task Elements ...... 2144 C. L. Bottasso, F. Scorcelletti, G. Maisano, A. Ragazzi

Parametric Investigations of Blade-Vortex Interaction using Large-Eddy Simulation...... 2187 Marcel Ilie, Fred Nitzsche, Edgar Matida

SESSION 10

PARALLEL SESSION A - DYNAMICS

Effect of Pretwist on Aeroelastic Response of a Rotor System with Dynamic Stall and Dynamic Wake...... 2197 V. Laxman, C. Venkatesan

Active Control of Helicopter's Gearbox Vibrations and Effects on the Cabin Noise...... 2297 Walter Corbetta, Edoardo Vigoni, Alessandro Toso, Gian Luca Ghiringhelli, Lorenzo Dozio, Fausto Cenedese

Effects of Nonlinearities on Ground Resonance Instability ...... 2327 Giulio Avanzini, Guido De Matteis

PARALLEL SESSION B - AERODYNAMICS

Turbulence Measurements in Blade Tip Vortices Using Dual-Plane Particle Image Velocimetry...... 2379 Bradley Johnson, Manikandan Ramasamy, J. Gordon Leishman

The Effect of Helicopter Configuration on the Fluid Dynamics of Brownout ...... 2398 Catriona Phillips, Richard E. Brown

Predicting the Wake Structure of the HART II Rotor using the Vorticity Transport Model...... 2427 Mary E. Kelly, Richard E. Brown

PARALLEL SESSION C – FLIGHT MECHANICS

Methods for Real-Time Rotor Stall Detection...... 2443 Ivan Grill, Manuj Dhingra, J. V. R. Prasad

In-flight Estimation of Helicopter Gross Weight and Mass Center Location...... 2482 M. Abraham, M. Costello

Helicopter Optimal Control in OEI Low Speed Flights ...... 2528 Przemyslaw Bibik, Janusz Narkiewicz

SESSION 11

PARALLEL SESSION A – AIRCRAFT SYSTEMS

Efficient Numerical Approaches for On-Board Rotorcraft Flight Performance Modeling ...... 2563 Norman E. Suhs, Charles Williams, Ronald Craft

Practical Prognostics for Helicopter CBM ...... 2597 Kenneth Pipe

PARALLEL SESSION B – AIRCRAFT DESIGN

Blade Shape Optimization for HSI Noise Reduction and Performance Improvement of Helicopter...... 2610 Sanghyun Chae, Kwanjung Yee, Choongmo Yang, Takashi Aoyama, Shinkyu Jeong, Shigeru Obayashi

Small Tiltrotor UAV Development and Conversion Flight Test...... 2653 Seong-Wook Choi, Youngshin Kang, Sungho Chang, Samok Koo, Jai Moo Kim

Author Index