Citation: Muhammed, M.; Virk, M.S.
Ice Accretion on Fixed-Wing
Unmanned Aerial Vehicle—A Review
Study. Drones 2022, 6, 86. https://
doi.org/10.3390/drones6040086
Academic Editors: Andrzej
Łukaszewicz, Wojciech Giernacki,
Zbigniew Kulesza, Jaroslaw Pytka
and Andriy Holovatyy
Received: 28 February 2022
Accepted: 20 March 2022
Published: 28 March 2022
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Review
Ice Accretion on Fixed-Wing Unmanned Aerial Vehicle—A
Review Study
Manaf Muhammed * and Muhammad Shakeel Virk
Arctic Technology & Icing Research Group, UiT—The Arctic University of Norway, 8514 Narvik, Norway;
muhammad.s.virk@uit.no
* Correspondence: manaf.muhammed@uit.no; Tel.: +47-98863857
Abstract:
Ice accretion on commercial aircraft operating at high Reynolds numbers has been exten-
sively studied in the literature, but a direct transformation of these results to an Unmanned Aerial
Vehicle (UAV) operating at low Reynolds numbers is not straightforward. Changes in Reynolds
number have a significant impact on the ice accretion physics. Previously, only a few researchers
worked in this area, but it is now gaining more attention due to the increasing applications of UAVs
in the modern world. As a result, an attempt is made to review existing scientific knowledge and
identify the knowledge gaps in this field of research. Ice accretion can deteriorate the aerodynamic
performance, structural integrity, and aircraft stability, necessitating optimal ice mitigation techniques.
This paper provides a comprehensive review of ice accretion on fixed-wing UAVs. It includes various
methodologies for studying and comprehending the physics of ice accretion on UAVs. The impact of
various environmental and geometric factors on ice accretion physics is reviewed, and knowledge
gaps are identified. The pros and cons of various ice detection and mitigation techniques developed
for UAVs are also discussed.
Keywords:
atmospheric icing; UAV; LWC; MVD; Reynolds number; aerodynamic penalties; IPS;
modal analysis
1. Introduction
UAV is an aircraft without an onboard human pilot. The main components of a UAV
are the aircraft structure, ground control center (remote), payload (camera), and a data
link for the communication between aircraft and ground control center [
1
]. According to
their structure, UAVs are classified into four broad categories: fixed-wing UAVs, rotary-wing
UAVs, flapping-wing UAVs, and blimps [
2
]. The smallest UAVs operate at less than 1200 feet
above ground level, while the largest can fly up to 60,000 feet. The size and cost of UAVs
vary according to application, ranging from pocket-sized micro-UAVs to large UAVs com-
parable in size to passenger aircraft. Even though crew safety is not a primary concern for
UAVs due to their unmanned nature, but due diligence must be exercised in the design
and manufacture of UAVs to avoid any financial losses. Historically, UAVs were used
exclusively for military and defense purposes. However, over the last decade, UAVs have
demonstrated their potential for use in various civil and public safety applications, in-
cluding mapping, surveying, and photography. In 2021, a German marketing consultancy
reported that UAVs have been used in 237 different applications [
3
]. As per the Unmanned
Aircraft System Roadmap 2005–2030 [
4
], currently, more than 250 models of UAVs are
manufactured globally by 32 nations.
With an increase in human activity in ice-prone high north regions, the use of UAVs
has increased as well, with potential applications including ice reconnaissance, determining
sea-ice thickness, surface roughness, and surface temperature over ice, water, and land, re-
trieving the spectral albedo of land surfaces, and monitoring coastal erosion [
5
]. UAVs also
play a critical role in emergency and catastrophe scenarios in cold regions [
6
]. In addition,
Drones 2022, 6, 86. https://doi.org/10.3390/drones6040086 https://www.mdpi.com/journal/drones
