Results 11 to 20 of about 17,805,085 (289)

Low Level Jet Wind Shear in the Sahel [PDF]

International Journal of Engineering Research in Africa, 2013
In the Sahel, a vertical wind shear appears in the dry and in the wet seasons. In Niamey, Niger, during the dry season, the period of strong shears is clearly linked to the Nocturnal Low Level Jet (LLJ) since it occurs in a narrow time period around 06H00 UTC at 60% of the cases reach shears which require an alert to the pilots (higher than 4 ms-1 per ...
Madougou, Saïdou, Saïd, Frédérique, Campistron, Bernard, Kebe, Cheikh Fadel   +3 more
openaire   +3 more sources

Airport low-level wind shear lidar observation at beijing capital international airport

EPJ Web of Conferences, 2018
Ocean University of China lidar team operated a pulse coherent Doppler lidar (PCDL) for the low level wind shear monitoring at the Beijing Capital International Airport (BCIA) in 2015. The experiment configuration, observation modes is presented.
Zhang Hongwei, Wu Songhua, Wang Qichao, Liu Bingyi, Zhai Xiaochun   +4 more
doaj   +3 more sources

Low Level Turbulence Detection For Airports [PDF]

International Journal of Aviation, Aeronautics, and Aerospace, 2019
—— Low level wind shear and turbulence present a serious safety risk to aircraft during the approach, landing and take-off phases. Despite many advances in on-board and ground based warning systems. Wind shear remains a formidable force that coupled with
Anthony O' Connor, Derek Kearney
doaj   +2 more sources

Study of the Algorithm for Wind Shear Detection with Lidar Based on Shear Intensity Factor

Algorithms, 2022
Low-level wind shear is a vital weather process affecting aircraft safety while taking off and landing and is known as the “aircraft killer” in the aviation industry. As a result, effective monitoring and warning are required.
Shijun Zhao, Yulong Shan
doaj   +2 more sources

Low-Level Wind Shear Identification along the Glide Path at BCIA by the Pulsed Coherent Doppler Lidar

Atmosphere, 2020
Low-level wind shear is usually to be a rapidly changing meteorological phenomenon that cannot be ignored in aviation security service by affecting the air speed of landing and take-off aircrafts. The lidar team in Ocean University of China (OUC) carried
Hongwei Zhang, Xiaoying Liu, Qichao Wang, Jianjun Zhang, Zhiqiang He, Xi Zhang, Rongzhong Li, Kailin Zhang, Junwu Tang, Songhua Wu   +9 more
doaj   +2 more sources

Wind Shear of Low-Level Jets and Their Influence on Manned and Unmanned Fixed-Wing Aircraft during Landing Approach [PDF]

Atmosphere, 2021
Wind shear at low altitudes represents a potential hazard to landing aircraft. Based on two wind lidar data sets of one year, the occurrence of low-level jets (LLJs), the vertical wind shear and the rotation of the wind direction were analysed. The lidar
Lutz Bretschneider, Rudolf Hankers, Shanna Schönhals, Jens-Michael Heimann, Astrid Lampert   +4 more
doaj   +2 more sources

Recognition of partial scanning low-level wind shear based on support vector machine

Advances in Mechanical Engineering, 2018
A majority of air crash is caused by low-level wind shear. That can affect the direction and velocity of the aircrafts. So, it is very necessary to recognize the low-level wind shear in a short time to make the early warning.
Yuechao Ma, Sining Li, Wei Lu
doaj   +2 more sources

Influence of Low‑Level Wind Shear on Flight Characteristics of Large Helicopters

Nanjing Hangkong Hangtian Daxue Xuebao
To analyze the influence of low-level wind shear on the flight characteristics of a large helicopter during takeoff， a wind shear model and a helicopter flight dynamics model coupled with wind interference are established.
YE Yi, CHEN Renliang, WEI Yuan
doaj   +2 more sources

Study on the influence of topography on wind shear numerical simulations based on WRF–CALMET [PDF]

Geoscientific Instrumentation, Methods and Data Systems
This study focuses on the critical issue of low-altitude wind shear, which is vital for aircraft safety during takeoff and landing. Using the WRF–CALMET model, we assess the impact of topography on low-level wind shear at Zhongchuan Airport.
X. Wang, Y. Lei, B. Shi, Z. Wang, X. Li, J. Wang   +5 more
doaj   +3 more sources

The WRF Model Forecast-Derived Low-Level Wind Shear Climatology over the United States Great Plains [PDF]

Energies, 2010
For wind resource assessment projects, it is common practice to use a power-law relationship (U(z) ~ zα) and a fixed shear exponent (α = 1=7) to extrapolate the observed wind speed from a low measurement level to high turbine hub-heights. However, recent
Sukanta Basu, Brandon Storm
doaj   +2 more sources