What are the types of drones and how are they classified?

Unmanned aerial vehicles (UAVs) or drones play a significant role across various industries and sectors. They’re proving adaptable, reliable, and effective. For example, drones provide transportation in logistics and delivery, search and rescue, infrastructure inspection, precision agriculture, disaster response, mining, urban planning, security, surveillance, and space exploration.

There are many different types of drones, classified in several ways. Drones are labeled by their design, size, application, or purpose. They can also be classified based on their power source, operating environment, and regulatory class. The range of this technology is large and growing.

In this article, we’ll describe some common types of drones and discuss their classification.

Drone types by design
Drones are most often classified by their design. Here are some of the most common types.

1. Single-rotor helicopter drones
2. Multi-rotor drones
3. Fixed-wing drones
4. Fixed-wing hybrid vertical take-off landing (VTOL) drones
5. Tilt-rotor drones
6. Ducted fan drones
7. Blended-wing body drones

Single-rotor helicopter drones feature a single, large rotor for lift and control (for altitude and direction) that works like a conventional manned helicopter. A combination of cyclic, collective, and tail rotor controls is applied to maneuver the flight precisely.

These drones are employed for various tasks, such as aerial photography, surveillance, remote sensing, and leisure flights. They can often carry heavier payloads and offer longer flight times compared to multi-rotor drones. They’re more challenging to operate than multi-rotor drones, so the pilots require proper training to understand the principles of rotorcraft flight and master the control inputs.

Multi-rotor drones use multiple propellers (blades) for flying and navigation, typically four to eight or more. The drones are named based on the number of rotors they have. For instance:

Tricopter – 3 rotors
Quadcopter – 4 rotors
Pentacopter – 5 rotors
Hexacopter – 6 rotors
Octocopter – 8 rotors
Decacopter – 10 rotors)
Dodecacopters – 12 rotors

The most common configurations are quadcopters, hexacopters, and octocopters.

A multi-rotor drone produces lift by quickly rotating its rotors. It can also hover, rise, and descend by the combined lift of the rotors. The drone remains stable by controlling the lift of each rotor. It can also alter its location, orientation, and direction by changing the speed and direction of each rotor. The opposing rotors’ pitch or speed is adjusted to regulate yaw.

These drones use differential thrust and speed adjustments across their rotors to achieve control. They’re relatively easy to operate and can hover in place without continuous pilot input, making them ideal for tasks like aerial photography, videography, and surveying. These drones have low payload capacities and relatively short flight times. They’re available in various sizes, from tiny toy drones for recreational use to larger professional and industrial models for specialized tasks.

Fixed-wing drones have fixed wings and a streamlined design, much like airplanes. Lift is generated through the wings (rather than rotors), which provide aerodynamics when air flows over them, and the drone moves forward. In fact, fixed-wing drones are inherently stable in flight due to their aerodynamic design.

This drone does have propellers, but they’re mounted on the front of the drone instead of the top, helping with forward thrust. Flight control is achieved through control surfaces such as ailerons, elevators, and rudders.

Unlike multi-rotors, fixed-wing drones cannot hover in place and require a runway or catapult for takeoff and landing. They must maintain continuous forward motion for lift, making them efficient for long-endurance missions. Designed for extended flight times, these drones can fly for several hours on a single battery charge or longer with fuel-powered engines. They can also carry heavy payloads and are capable of autonomous flight, allowing them to follow pre-programmed flight paths or respond to specific mission objectives without constant pilot input.

As a result, fixed-wing drones are commonly used for applications such as aerial mapping, agriculture (e.g., crop monitoring), environmental monitoring, long-range surveillance, wildlife tracking, and geospatial data collection.

Hybrid VTOL drones combine the features of fixed-wing and multi-rotor drones. They’re capable of vertical takeoff and landing like multi-rotor drones, so they can operate in confined spaces without a runway or catapult launch. These drones also have fixed-wing capabilities, meaning they can transition from vertical takeoff to horizontal flight, similar to airplanes.

Once in flight mode, they cover longer distances more efficiently than multi-rotor drones. These hybrids use advanced flight control systems to transition between vertical takeoff and fixed-wing flight. The transition process typically involves changing the orientation of the drone’s rotors and adjusting thrust vectors. After completing their missions, hybrid VTOLs can return to a vertical landing, allowing them to land in tight spaces or on small landing platforms. Many hybrid VTOL drones also have autonomous flight capabilities.

These drones can carry a large payload and cover long distances, making them useful for aerial mapping, surveillance, cargo delivery, and environmental monitoring.

Tilt-rotor drones combine the features of a helicopter and a fixed-wing aircraft. They have rotor systems that can tilt from a vertical to a horizontal position, allowing them to take off and land vertically like a helicopter and then transition to fixed-wing flight for efficient cruising.

In the vertical position, the rotors provide vertical lift for takeoff and landing. In the horizontal position, the rotors act like propellers for forward flight. These drones use advanced flight control systems, which efficiently manage the vertical and horizontal transitions. This involves changing the orientation of the rotors and adjusting thrust vectors. Many have autonomous flight capabilities.

Tilt-rotor drones typically carry large payloads, cover long distances, and are used for long-range reconnaissance, surveillance, and transportation of goods in remote or challenging environments.

Ducted fan drones have a propulsion system comprising one or more fans encased within a protective duct or shroud. This means they can leverage the advantages of ducted fans for various applications. The duct protects the fan blades and provides additional lift and control. It also ensures the blades are protected and won’t damage or injure in the case of a collision.

These drones benefit from increased lift and stability compared to open-rotor designs. The ducted fan also produces less noise than open-rotor configurations. By varying the speed and direction of rotation of the fans, the drone controls its movement in different directions. The duct provides added aerodynamic lift, making them more efficient for hovering and slow-speed flight.

These drones are more compact and smaller compared to other types. Due to a smaller footprint, there are limitations in payload capacity compared to larger UAVs. Ducted fan drones are used for specialized tasks like inspecting pipes, tunnels, and indoor structures where maneuverability and stability are critical.

Blended wing body (BWB) drones have a blended wing and fuselage design for improved aerodynamics, which is unique. The design results in a wing-like, lifting body with minimal distinction between the main body and the wings. This drone relies on its body to generate lift. The blended shape creates lift through aerodynamic forces and its overall shape. There could be one or more propellers or jet engines to provide thrust for forward motion. Some BWB drones are designed with VTOL capabilities, allowing them to take off and land vertically.

BWB drones can carry large payloads and cover longer distances with decent fuel efficiency. They’re used for aerial mapping, surveillance, cargo delivery, scientific research, and military reconnaissance. Their efficiency and payload capacity make them versatile machines for many industries.

Drone types by size
The weight and size range for the classification of drones can vary depending on local regulations and standards. In the United States, the Federal Aviation Administration (FAA) classifies drones based on their weight to establish rules and regulations for their safe operation. These regulations may include restrictions on where and how drones can be flown, registration requirements, and pilot certification.

As advancements in drone technology occur, classification criteria changes. Currently, the classification of drones based on size is listed below.

1. Nano
2. Micro
3. Mini
4. Small
5. Medium
6. Large

Nano drones are typically less than 250 grams and small enough to fit in the palm of your hand. They’re used for indoor and outdoor recreational flying, educational purposes, and basic aerial photography.

Micro drones weigh between 250 grams and two kilograms. They’re slightly larger than nano drones but still compact. Micro drones are used for recreational flying, aerial photography, and educational purposes.

Mini drones weigh between two and 25 kilograms. They’re larger than micro drones but still relatively small. Mini drones are used for aerial photography, videography, recreational flying, and professional applications like agriculture and surveying.

Small drones weigh between 25 and 150 kilograms. They’re larger and more substantial than mini drones. Small drones are used in applications like surveillance, inspection, aerial mapping, and cargo transport.

Medium drones weigh between 150 and 600 kilograms. They’re used in advanced professional applications, such as agricultural spraying, environmental monitoring, and some military or defense applications.

Large drones weigh between 600 kilograms and several tons. They’re so large that they resemble small aircraft. Large drones are used for heavy cargo transport, military reconnaissance, long-range surveillance, and large-scale mapping and surveying.

Drone types by technology
Typically, drones are a type of unmanned aerial vehicle. However, as technology is advancing, drones include new devices. Various unmanned or remotely controlled vehicles are now also referred to as drones.

These drones are categorized based on the type of vehicle they are:

1. Unmanned Aerial Vehicles (UAV)
2. Unmanned Underwater Vehicles (UUV)
3. Micro Aerial Vehicles (MAV)
4. Nano Aerial Vehicles (NAV)
5. Personal Aerial Vehicles (PAV)
6. Submersible Drones (SD)

Unmanned Aerial Vehicles (UAVs) is an aircraft that operates without a human pilot on board. These vehicles can be designed to fly autonomously, following predetermined flight patterns or reacting to real-time data — or a human operator can remotely control them.

Unmanned Underwater Vehicles (UUVs) are autonomous or remotely operated vehicles designed to operate beneath the water’s surface without a human pilot. They’re used in various applications, including oceanography, marine biology, underwater archaeology, hydrographic surveying, underwater resource exploration, and military tasks such as mine countermeasures, anti-submarine warfare, as well as intelligence, surveillance, and reconnaissance (ISR).

Micro Aerial Vehicles (MAV) are small, lightweight unmanned aerial vehicles. These tiny aircraft are often designed to mimic the flight characteristics of insects or birds and are typically used for applications requiring small, agile drones. They’re used for indoor mapping, monitoring confined spaces, or swarming for surveillance.

Nano Aerial Vehicles (NAV) are extremely small, lightweight, and agile drones for specific applications requiring micro-sized aircraft. Their design is also inspired by the flight characteristics of insects and is used for tasks such as surveillance, reconnaissance, and environmental monitoring in tight or confined spaces.

Personal Aerial Vehicles (PAV) transport one or more passengers, typically in a small, compact, and often electric-powered vehicle. They’re being developed to provide regional and urban transportation options, potentially reducing traffic congestion and offering future forms of efficient and practical personal transportation. A good example of PAVs is air taxis.

Submersible Drones (SD), also known as underwater drones or remotely operated underwater vehicles (ROVs), are autonomous or remotely controlled vehicles designed to operate underwater. They’re used for exploring underwater environments that are difficult or dangerous for humans to access. They can reach great depths in the ocean and explore underwater caves, shipwrecks, and other submerged features. These drones are used for underwater exploration, oceanography, underwater archaeology, and recreational purposes.

Drone types by application
Drones are versatile machines used in many applications and equipped accordingly. Here are a few drone types based on purpose.

Photography and videography drones capture high-quality images and videos from the air. They’re equipped with stabilized gimbals and high-resolution cameras. They’re used in filmmaking, aerial photography, and content creation.

Agricultural drones are used in agriculture for crop monitoring, pest control, and precision agriculture. They have sensors for collecting data on crop health and soil conditions.

Search and rescue drones aid in search and rescue operations by providing real-time aerial imagery. They have thermal cameras and sensors for locating missing persons in challenging terrain.

Racing drones are used for recreational purposes and drone racing competitions. They offer speed, agility, and performing aerobatic maneuvers.

Entertainment and show drones are used in large-scale entertainment events and aerial light shows. They’re programmed to create coordinated visual displays in the night sky and often have laser or LED lights.

Delivery drones transport goods from one location to another, typically for e-commerce or logistics companies.

Mapping and surveying drones are used for creating detailed maps, 3D models, and topographic surveys of terrain. They’re commonly used in construction, mining, and land development.

Military and defense drones (UCAVs – Unmanned Combat Aerial Vehicles) are used by armed forces for reconnaissance, surveillance, and sometimes combat missions. These may range from small surveillance drones to larger armed platforms.

Scientific research drones are used for various scientific purposes, including climate research, atmospheric sampling, and geological surveys.

Educational and training drones are designed for educational purposes and training new drone operators. They provide a safe and controlled environment for learning about UAV technology.

Infrastructure inspection drones inspect critical infrastructure like bridges, power lines, and pipelines. With the help of these drones, there’s often no need for human inspectors to work in hazardous conditions.

Oil and gas industry drones are used in oil and gas operations for pipeline monitoring, flare stack inspection, and offshore rig maintenance.

Environmental monitoring drones are used for ecological research and conservation. They help in wildlife tracking, habitat monitoring, and assessing ecological changes.

Healthcare and medical drones are under development and may be used for medical supply transportation, organ delivery, and emergency medical response.

Space exploration drones (planetary rovers) are used for planetary exploration on celestial bodies like Mars and the moon. They collect data and images to advance our understanding of space and the planets.

Drone types by environment
Drones can also be categorized based on the environment where they operate as follows.

Indoor drones are designed for flying within indoor environments such as warehouses, factories, and indoor arenas. These micro or mini drones can navigate tight spaces and are used for indoor mapping, inventory management, and inspections.

Outdoor drones operate in open outdoor spaces, ranging from rural areas to urban environments. They’re used for aerial photography, surveillance, agriculture, and recreational flying.

Urban drones are used in urban environments, which require obstacle avoidance systems and the ability to navigate complex airspace. They’re used for urban surveillance, infrastructure inspection, and aerial photography in cities.

Rural and agricultural drones typically fly in open fields, farmlands, and rural areas. They’re used for precision agriculture, crop monitoring, and pesticide application.

Mountain and high-altitude drones are equipped for operation in mountainous or high-altitude environments, often featuring enhanced altitude capabilities and rugged designs. They’re commonly used for mountain search and rescue or alpine surveys.

Maritime drones operate on or under the water, including oceans, seas, rivers, and lakes. They’re used in ocean exploration, marine research, underwater inspections, and search and rescue missions.

Coastal and marine drones are built to withstand the corrosive effects of saltwater and operate in coastal and marine environments. They’re used for coastal monitoring, marine research, and ocean conservation efforts.

Desert drones can withstand high temperatures, blowing sand, and low humidity in desert environments. They’re used for desert terrain mapping, monitoring, and environmental research.

Forest and wildfire drones monitor and manage forested areas, detect wildfires, and map forest health. They help in wildfire prevention and response efforts.

Jungle and rainforest drones navigate dense vegetation and high humidity in tropical rainforests and jungles. They’re used for biodiversity research, environmental monitoring, and wildlife conservation.

Alpine drones are designed for snowy and alpine environments and are often used for avalanche monitoring, snowpack analysis, and winter search and rescue.

Arctic and antarctic drones can withstand extreme cold, harsh conditions, and icy environments in polar regions. They’re used for scientific research, environmental monitoring, and wildlife observation in Arctic and Antarctic regions.

Underground drones are used in mining and tunneling operations to navigate and inspect underground passages. They ensure safety and efficiency in subterranean environments.

Space exploration drones are used in planetary exploration on celestial bodies like Mars and the moon.

Extreme weather drones are engineered to withstand severe weather conditions such as hurricanes, tornadoes, and other extreme weather events. They’re used for weather research and monitoring.

Drone types by autonomy and control
These drones are categorized by the level of autonomy and control they possess.

Manual drones are controlled entirely by a human operator.

Semi-autonomous drones perform some tasks autonomously but with human oversight.

Autonomous drones are engineered to operate without direct human intervention. They rely on sensors and artificial intelligence for autonomous flight and mission completion.

Drone types by power source
Based on power sources, there are the following types of drones.

Battery-powered drones include electric drones powered by rechargeable lithium-polymer (LiPo) or lithium-ion (Li-ion) batteries. They’re commonly used for consumer and professional use. However, because of the use of a battery, they have limited flight time and require periodic recharging. These drones are lightweight and suitable for a wide range of applications. They operate quietly and have zero emissions.

Gasoline-powered drones operate on internal combustion engines that run on gasoline or other liquid fuels. Compared to battery-powered drones, these drones have longer flight times and can carry heavy payloads. These are typically large drones designed for extended missions.

Hybrid drones combine electric and gasoline power sources to balance extended flight duration and reduced emissions. They’re more versatile and heavier than electric or gasoline drones.

Solar-powered drones have panels on their wings or surfaces to capture solar energy and recharge onboard batteries. They depend on sunlight for recharging, so they have limited flight in cloudy and nighttime conditions. However, they’re eco-friendly and exhibit extended flight endurance when exposed to sunlight.

Fuel-cell-powered drones use hydrogen fuel cells to generate electricity for propulsion and onboard systems. These drones show long-flight endurance, excellent energy efficiency, and reduced emissions. However, they’re costly, and there’s limited hydrogen refueling infrastructure.

Tethered drones receive power and data through the tether. They remain connected to a ground-based power source via a cable (tether), which gives them unlimited flight time (as long as tethered), continuous power, and stable communication. However, their mobility, altitude, and range are limited.

Nuclear-powered drones are under development and may use small nuclear reactors as a power source for extended missions, particularly in space exploration. They’re complex and expensive to design and engineer. These drones are only a theoretical concept with potential for extremely long missions, particularly in deep space.

Drone types by regulatory class
There are different regulatory bodies for drones in most countries. The regulatory body for drones is as follows per these countries:

The Federal Aviation Administration (FAA) is the U.S.
The European Union Aviation Safety Agency (EASA) in the European Union
The Civil Aviation Authority (CAA) in the United Kingdom
The Directorate General of Civil Aviation (DGCA) in India.

The most common regulatory classes for drones are as follows:

Open class includes drones that weigh less than 250 grams and have a maximum speed of 19 m/s. These drones are subject to the least restrictions and can be flown without a license or registration.

Specific class includes drones that do not meet the requirements of the open class. These drones may require a license, registration, or other authorization to fly.

Certified class includes drones that are designed for commercial or industrial use. These drones must meet rigorous safety standards and are subject to the most stringent regulations.