• Aerodynamic modeling of the Skywalker X8 Fixed-Wing Unmanned Aerial Vehicle 

      Gryte, Kristoffer; Hann, Richard; Alam, Mushfiqul; Rohac, Jan; Johansen, Tor Arne; Fossen, Thor I. (Chapter, 2018)
      With advanced control, estimation and simulation requirements in unmanned aerial systems comes the need for sophisticated aerodynamic models. This paper reviews two common means for establishing such models; numerical ...
    • Atmospheric Ice Accretions, Aerodynamic Icing Penalties, and Ice Protection Systems on Unmanned Aerial Vehicles 

      Hann, Richard (Doctoral theses at NTNU;2020:200, Doctoral thesis, 2020)
      This thesis focused on atmospheric ice accretions, aerodynamic icing penalties, and ice protection systems (IPS) on fixed-wing unmanned aerial vehicles (UAVs). The motivation for this work was to increase the knowledge ...
    • Derivation of flow rate and calibration method for high-volume air samplers 

      Hann, Richard; Hermanson, Mark H (Journal article; Peer reviewed, 2019)
      High-volume air sampling is a key measurement technique for investigating the concentration of atmospheric pollutants. Despite being a mature technique, a detailed description of how to derive flow rates and how to calibrate ...
    • Experimental and numerical icing penalties of an S826 airfoil at low Reynolds numbers 

      Hann, Richard; Hearst, R. Jason; Sætran, Lars Roar; Bracchi, Tania (Peer reviewed; Journal article, 2020)
      Most icing research focuses on the high Reynolds number regime and manned aviation. Information on icing at low Reynolds numbers, as it is encountered by wind turbines and unmanned aerial vehicles, is less available, and ...
    • Experimental Investigations of an Icing Protection System for UAVs 

      Hann, Richard; Borup, Kasper Trolle; Zolich, Artur Piotr; Sørensen, Kim Lynge; Vestad, Håvard Nitter; Steinert, Martin; Johansen, Tor Arne (Journal article; Peer reviewed, 2019)
      UAV icing is a severe challenge that has only recently shifted into the focus of research. Today, there are no mature icing mitigation technologies for UAVs, except for the largest fixed-wing drones. We are working on the ...
    • Experimental Investigations of an Icing Protection System for UAVs 

      Hann, Richard; Borup, Kasper Trolle; Zolich, Artur Piotr; Sørensen, Kim Lynge; Vestad, Håvard Nitter; Steinert, Martin; Johansen, Tor Arne (Journal article; Peer reviewed, 2019)
    • Impact of Atmospheric Icing on UAV Aerodynamic Performance 

      Hann, Richard; Wenz, Andreas Wolfgang; Gryte, Kristoffer; Johansen, Tor Arne (Chapter; Conference object, 2017)
      This paper presents a first assessment on the impact of atmospheric icing on the aerodynamic performance of fixed-wing UAVs. Numerical simulations were performed in order to evaluate the impact on lift and drag on a 2D ...
    • Long range path planning using an aircraft performance model for battery powered sUAS equipped with icing protection system 

      Hovenburg, Anthony Reinier; Andrade, Fabio; Hann, Richard; Rodin, Christopher D; Johansen, Tor Arne (Journal article, 2020)
      Earlier studies demonstrate that en-route atmospheric parameters, such as winds and icing conditions, significantly affect the safety, and in-flight performance of unmanned aerial systems. Nowadays, the inclusion of ...
    • Optimal Mission Planning for Fixed-Wing UAVs with Electro-Thermal Icing Protection and Hybrid-Electric Power Systems 

      Narum, Edvard Frimann Løes; Hann, Richard; Johansen, Tor Arne (Chapter, 2020)
      Harsh weather conditions such as wind and icing are severe debilitators to the operations of unmanned aerial vehicles in terms of performance, safety and reliability. Forecasts of atmospheric parameters in the mission area ...
    • SIOS’s Earth Observation (EO), Remote Sensing (RS), and operational activities in response to COVID-19 

      Jawak, Shridhar D.; Andersen, Bo N.; Pohjola, Veijo; Godøy, Øystein; Hübner, Christiane E.; Jennings, Inger; Ignatiuk, Dariusz; Holmen, Kim; Sivertsen, Agnar; Hann, Richard; Tømmervik, Hans; Kääb, Andreas; Błaszczyk, Małgorzata; Salzano, Roberto; Luks, Bartłomiej; Høgda, Kjell Arild; Storvold, Rune; Nilsen, Lennart; Salvatori, Rosamaria; Krishnan, Kottekkatu Padinchati; Chatterjee, Sourav; Lorentzen, Dag Arne; Erlandsson, Rasmus; Lauknes, Tom Rune; Malnes, Eirik; Karlsen, Stein Rune; Enomoto, Hiroyuki; Fjæraa, Ann Mari; Zhang, Jie; Marty, Sabine; Nygård, Knut Ove; Lihavainen, Heikki (Peer reviewed; Journal article, 2021)
      Svalbard Integrated Arctic Earth Observing System (SIOS) is an international partnership of research institutions studying the environment and climate in and around Svalbard. SIOS is developing an efficient observing system, ...
    • UAV Icing: Ice Accretion Experiments and Validation 

      Hann, Richard (Journal article; Peer reviewed, 2019)
      Atmospheric icing is a key challenge to the operational envelope of medium-sized fixed-wing UAVs. Today, several numeric icing codes exist, that all have been developed for general aviation applications. UAVs with wingspans ...