On 5th October, Dr Martin Fengler, Meteomatics CEO presented at the AUVSI Xponential 2020, on how Meteomatics has overcome the impacts of icing on our weather drones (Meteodrones),  

Meteomatics Meteodrones

Meteomatics Meteodrone

Meteomatics was thrilled to be invited by The National Center for Atmospheric Research (NCAR) to present at the AUVSI Xponential Unmanned Systems Industry Event; Monday 5th October 2020, along with other industry thought leaders, including The Federal Aviation Administration and University Corporation for Atmospheric Research (UCAR)

Meteomatics CEO, Dr Martin Fengler was happy to present details of the cutting edge design and engineering that have enabled Meteomatics’ Meteodrones to overcome the challenges of icing and other meteorological phenomena that can be encountered when flying in severe weather.

Across the globe, severe weather impacts the economies and safety of populations, such as thunderstorms and hail that can cause extensive damage.

Global weather forecasting centres, such as ECMWF, United States’ National Weather Service and the UK’s Met Office, collect an understanding of the atmosphere to help them inform the initial starting conditions of their weather models.

However, the global weather community has realised that the current operational observing systems are lacking data in the planetary boundary layer which can impact the forecasting of severe weather.

Inconsistency in observational data coverage

Inconsistency in observational data coverage

Dr Martin Fengler, CEO at Meteomatics, says that “The current atmospheric observing systems fail to provide a satisfactory amount of spatially and temporally-resolved observations of atmospheric parameters in the planetary boundary layer (PBL) despite their potential positive impact on numerical weather prediction (NWP). This is particularly critical for humidity, which exhibits a very high variability in space and time or for the vertical distribution of temperature, determining the atmosphere’s stability“”.

Some weather forecasting centres are increasing the amount of satellite data they use and there are calls to increase the number of radiosonde flights (balloons filled with helium gas, carrying weather instruments) - both of which have their limitations.

Whilst satellite data provides a lot of information on temperature and humidity fields, it provides less data on wind fields. Plus, a closer look at satellite data reveals a gap in the planetary boundary layer (PBL), i.e. the first 1 to 2 km above ground level (AGL). This is crucial because weather phenomena such as fog, low cloud and storms form at this altitude.

Radiosondes do offer an alternative. However, it’s difficult for national weather centers to increase the number of radiosonde flights, as the equipment they carry can be expensive to manufacture, the data isn’t localised as the balloon drifts across areas that might not be of interest, they are filled with helium gas that is becoming a scarce natural resource and radiosondes are commonly lost after deployment, as they are carried away with the wind.

Meteomatics weather drones fill the observation gap in the PBL

Meteomatics’ weather drones fill the observation gap in the PBL

Meteomatic's Meteodrones offer global weather forecasters and other interested parties a reliable and scientifically robust method of collecting weather observations. Meteodrones are engineered specifically for collecting weather observations and can operate in some of the most challenging weather conditions (e.g. severe thunderstorms – test flight completed with NOAA’s National Severe Storms Laboratory in the USA). Plus, they are certified to fly beyond visual line of sight (BVLOS) and can fly up to 6 km into the atmosphere, collecting weather observations throughout their flight.

Meteomatics Meteodrone

Meteodrone severe storm edition (SSE)

 

Overcoming the demands of operating a drone in a wide variety of weather situations, altitude and fly BVLOS, requires Meteodrones to rely on their onboard instrumentation to detect the presence of icing conditions or icing accretions on their airframe. Leading to Meteomatics reinventing the design of UAV’s to overcome the issue of blade icing, without compromising the flight length of a Meteodrone.

Dr Martin Fengler, highlighted the severity of icing risk for Meteodrones, by explaining; “That the propellers of the drone platforms can freeze at temperatures below 0°C (32°F) and high humidity very quickly, whereby the flow at the rotors can deteriorate so much that it leads to the drone crashing”.

The Meteomatics Drone Team have now developed a patent pending anti-icing system that is triggered when an icing event is detected and heats the rotor blades, to safely bring the Meteodrone back to its ground station and minimise the risk of catastrophic failure. 

Junfraujoch Altitude Research Station

Flight testing at Junfraujoch High Altitude Research Station, Switzerland, 3884 meters ASL.

Meteodrone ice buildup after 180 seconds without heating system activated, at temperature of -14 °C

Meteodrone ice buildup after 180 seconds without heating system activated, at temperature of -14 °C

Dr Martin Fengler, also illustrated how the heating system has been tested and developed in very challenging conditions, revealing the rotor blades were tested back in 2018 on Mount Säntis in Switzerland; at 2,502m (8,208ft) above sea level it is the highest mountain in the Alpstein region. Under icy conditions (air temperature -9.2 °C [15.4 °F], relative humidity 95 %, 20 km/h [12 mph] wind) the efficiency of various heating systems with different power classes was investigated. 

At the end of March 2018, further tests were carried out at Rail Tech Arsenal’s Climatic Wind Tunnel in Vienna, where even more extreme weather conditions were created to test the performance of the Meteodrone, ranging from -4°C, 100 % relative humidity [dense fog] and wind speeds around 95 km/h [59 mph]). In these conditions, the entire experimental setup freezes in the wind in a very short time. However, by using a redeveloped heating system with increased heating power, the rotor blades could be kept almost completely ice-free. Thus, Meteomatics was able to record a milestone in the development of a drone anti-icing system.

Thermal image of Meteodrone anti-icing system in action, keeping the rotor blades ice free

Thermal image of Meteodrone anti-icing system in action, keeping the rotor blades ice free

Meteomatics’ is now flying its Meteodrones operationally, delivering valuable weather observations and allowing Meteomatics to ingest these observations into models (such as WRF), without implementing any additional forward observational operators. The data can be directly assimilated like any radiosonde data.

Global forecasting centers are already purchasing weather drones, with Meteomatics supplying NOAA (United States National Oceanic and Atmospheric Administration). Meteomatics is already experiencing interest from other both public and commercial institutions as more organisations are becoming aware of the unique capabilities and data offered by Meteodrones.

Meteomatics has published a white paper that contains further details on the capabilities of its drones and a number of case studies, accessible - here  

For further information on the Meteodrones, please contact sales@meteomatics.com