Results 41 to 50 of about 7,948 (233)
Main rotor-tail rotor intraction and its implications for helicopter directional control
, 2008 Aerodynamic interference between the main and tail rotor can have a strong negative influence on the flight mechanics of a conventional helicopter. Significant unsteadiness in the tail rotor loading is encountered under certain flight conditions, but the
Fletcher, Timothy M. +2 more
core +1 more source
Helicopter tail rotor thrust and main rotor wake coupling in crosswind flight
, 2010 The tail rotor of a helicopter with a single main rotor configuration can experience a significant reduction in thrust when the aircraft operates in crosswind flight. Brown’s vorticity transport model has been used to simulate a main rotor and tail rotor
Fletcher, Timothy M. +3 more
core +1 more source
The Evolution of Autonomous Systems for Planetary Cave Exploration: A Review
Journal of Field Robotics, EarlyView.ABSTRACT The exploration of Subsurface Access Points (SAPs), such as lava tubes on the Moon and Mars, has gained significant interest due to their potential as stable environments shielded from surface radiation and temperature extremes. These sites are considered high‐value targets for detecting water and signs of ancient life, and assessing their ...
Sarah Swinton +4 more
wiley +1 more source
Strategic Management Journal, EarlyView.Abstract Research Summary Despite the importance of resource reallocation in shaping a variety of strategic outcomes, strategy scholars have paid only limited attention to the processes by which firms reallocate their resources across successive systemic innovations.
Gino Cattani +2 more
wiley +1 more source
Monitoring wildlife using long‐endurance solar‐electric UAVs
Wildlife Biology, EarlyView.This report discusses the effectiveness of using small solar‐electric UAV (uncrewed aerial vehicles) for aerial wildlife monitoring. We review four years of aerial wildlife monitoring missions using a 5.5‐m wingspan, solar‐electric UAV that was equipped with a gimballed IR/RGB camera.
Götz Bramesfeld +3 more
wiley +1 more source
Vox Sanguinis, Volume 121, Issue 6, Page 700-709, June 2026.Abstract Blood transfusion is life‐saving for patients in emergencies, but low‐ and middle‐income countries (LMICs) often face a severe shortage of banked blood. Establishing blood banks in rural areas presents substantial logistical and economic challenges for many LMICs.
Suvro Sankha Datta +4 more
wiley +1 more source
Aeroacoustic analysis of main rotor and tail rotor interaction [PDF]
, 2008 The increased restrictions placed on helicopter noise levels over recent decades have encouraged manufacturers to better understand tail rotor noise and its aerodynamic sources.
Fletcher, Timothy M. +5 more
core
IEEE Access, 2022 For the typical multi-component periodic micro-Doppler signal parameter estimation, a helicopter rotor feature extraction method based on flicker phenomenon and phase compensation is proposed in this paper.
Saiqiang Xia +6 more
doaj +1 more source
Wind Energy, Volume 29, Issue 5, May 2026.ABSTRACT Yaw engineering models are commonly used as add‐ons to the industrial blade element momentum (BEM) framework to improve load and power predictions by accounting for the skewed wake effect. However, existing yaw engineering models show noticeable limitations in accurately predicting the induced velocity distribution across the blade span.
Haoyuan Sun, Andrea Sciacchitano, Wei Yu
wiley +1 more source
Instability zones for isotropic and anisotropic multiblades rotor configurations [PDF]
, 2010 Helicopter ground resonance is an unstable dynamic phenomenon which can lead to the total destruction of the aircraft during take-off or landing phases. The earliest research in this domain was done by Coleman and Feingold around the 60's decade.
Leonardo Sanches +9 more
core +1 more source