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Demonstration of LIDAR-based wake vortex detection system incorporating an Atmospheric Hazard Map

State of the Art - Background

Tags: Air


Wake vortices and wind shear are potential causes of accidents and injuries to passengers and crew of all aircraft types. They cannot be detected by sight and result in sudden disruption to the aircraft's trajectory, potentially resulting in a crash if encountered during take-off or landing. There are currently few options for protection against these phenomena, and the main way of reducing accidents due to wake vortices is to impose mandatory separation times between aircraft which can affect the operating performance of airports from the resulting delays.

Wake vortex and wind shear detection is therefore the focus of research programmes funded within Europe and the USA, and the LIDAR technique (LIght Detection And Ranging) has already been shown to offer a technical solution for detecting wake vortices and wind shear. Since LIDAR requires the use of a LASER, there is a considerable challenge to design and build a system with the performance required to detect the hazard that is suitable for installation on aircraft, and which also meets the safety, performance and cost requirements of the aerospace industry.


The objective of Green-Wake is to develop and validate innovative technologies that will detect the hazards in a timely manner to improve passenger safety and comfort, and improve the operating efficiency of airports by providing a safe means to decrease separation times between trailing aircraft.

Green-Wake will develop and test an Imaging Doppler LIDAR system that is capable of detecting and measuring wake vortexes and wind shear phenomena 50-100 metres in front of an aircraft, allowing action to be taken to reduce or avoid the hazard. The aim of the project is to develop a system suitable for integration into a commercial aircraft, but also to look at how data are to be presented to the aircrew.

Firstly, a simulation will be developed which allows modelling the large number of variables involved in order to understand how optimum performance can be achieved. This requires a well-developed understanding of the requirements of the users, the meteorology of the hazard phenomena and the state of the art in the optical and hardware engineering.

Based on the outcomes of the modelling a new wind shear and wake vortex imaging Doppler LIDAR system will then be developed and implemented. A prototype will be used to determine the overall performance of the system.

Description of Work

There are four main innovations involved in Green-Wake.

The first is the extension of existing modelling and simulation research to allow development of the Green-Wake project simulation. This will allow for a cost-effective design of a system which is optimised for the application, despite the enormous number of variables involved.

The second innovation is a fast scanning system. This is a requirement due to the large volume of airspace in front of the aircraft which must be scanned and data gathered at sufficient density to allow for the effective detection of the hazard.

The third is in the data collection. Scanning a large volume in front of the aircraft requires fast and accurate processing. A new detector will be developed as part of the project which will permit the degree of real-time data handling required, and the techniques will be investigated for analysing the data generated and providing information in a suitable format for the aircrew.

Finally, the integration of the wind shear and wake vortex data into an overall map of features local to the aircraft will be researched. The objective is to deliver warnings of potential hazards most effectively to the aircrew.

Expected Results

This project is building on research from previous Framework Programme projects and extending it in order to develop an imaging Doppler LIDAR system which is capable of detecting wake vortices and wind shear, but which is also suitable for installation in aircraft. The aim of the project is to produce a system which can ultimately be developed into a commercial product which will enhance the safety of aircraft passengers and crew, and permit more effective use of runways at congested airports. This will not only enhance the safety of citizens travelling by air but also reduce unnecessary delays in take-off and landings, increasing traveller convenience and reducing fuel consumption from aircraft being held up. This contributes to the ACARE environmental goals for 2020.

The consortium is composed of a relatively high proportion of SMEs for whom the commercial potential of the project is a major driver. No product of the type and capability envisaged is currently available anywhere in the world.

The main products from the project are the simulator which will allow the investigation and optimisation of the system which is to be built, and the system itself which will be designed, built and evaluated within the project. The outcomes of the project will be documented in a series of written deliverables, and will be disseminated in accordance with the project dissemination plan.

Sensor and control system concept V02
Sensor and control system concept V02