L3.05: Drones


A drone is an unmanned aerial vehicle (UAV) and also referred to as an unpiloted aerial vehicle (UPV) or a remotely piloted aircraft (RPA). The following discussion was developed as part of GEOG 597G, Geospatial Applications for Unmanned Aerial System (UAS) by Penn State's College of Earth and Mineral Sciences and is licensed under CC BY 3.0.

UAS History

Here you will learn about the history of UAS development and its introduction to civilian and military applications. The history of flying objects, or the unmanned aerial vehicle in its rudimentary forms, extends way back to ancient civilizations. The Chinese, around 200 AD, used paper balloons (equipped with oil lamps to heat the air) to fly over their enemies after dark, which caused fear among the enemy soldiers who believed that there was divine power involved in the flight.

The idea of unmanned aerial objects came long before manned flights. This was for the obvious reason of removing the risk of loss of life in conjunction with these experimental objects. In modern times, the idea of unmanned flying objects developed to mean flying aerial vehicles, or aircraft without pilots on board. Thanks to advancements in technology, the maneuvering and control of piloted flight can be sufficiently mimicked. Names like aerial torpedo, radio controlled vehicle, remotely piloted vehicle (RPV), remote controlled vehicle, autonomous controlled vehicle, pilotless vehicle, unmanned aerial vehicle (UAV), unmanned aircraft system (UAS), and drone are names that may be used to describe a flying object or machine without a pilot on board.

The main challenge that faced early aerospace pioneers of piloted and pilotless airplanes alike was the issue of controlling flight once the flying object was up in the air. The Wright Brothers (1903), and at about the same time, Dr. Samuel Pierpont Langley, taught the aviation world a lot about the secrets of controlled flight. Afterwards, the war machine of WWI put intense pressure on inventors and scientists to come up with innovations in all aspects of flight design including power plants, fuselage structures, lifting wing configurations and control surface arrangements. By the time WWI ended, modern day aviation had been born.

In late 1916, the US navy funded Sperry Gyroscope Company (later named Sperry Corporation) to develop an unmanned torpedo that could fly a guided distance of 1000 yards to detonate its warhead close enough to an enemy warship. Almost two years later, on March 6, 1918, after a series of failures, Sperry efforts succeeded in launching an unmanned torpedo to fly a 1000-yard course in stable guided flight. It dived onto its target at the desired time and place, and later was recovered and landed. With this successful flight, the world’s first unmanned aircraft system, which is called Curtis N-9, was born.

In the late 1930s, the U.S. Navy returned to the development of drones. This was highlighted by the Navy Research Lab’s development of the Curtis N2C-2 drone. (See Figure 3.15). The 2500-lb. bi-plane was instrumental in testing the accuracy and efficiency of the Navy anti-aircraft defense system.

Example of the Curtis N2C-2 Drone
Figure 3.15: The Curtis N2C-2 Drone

Drones in Agriculture

Penn State Extension is testing drones to determine possible uses of drones for such purposes as observing pest control and fertilizer application patterns. Monitoring these types of things from the air can help growers with crop management decisions. Click on the image below to watch a short video (:36) about using drones in crop management.

If you are interested in reading the accompanying story, you can use the following link to access the "Penn State crop educator explores drone-driven crop management" article.

UAS System Overview

The way a pilotless aircraft is controlled determines its categorization. In general, there are three main names for pilotless aircraft:

  • Unmanned Aerial Vehicle (UAV): a pilotless aircraft that is either manually controlled with a joystick or a mouse or autonomously flown by following a preprogrammed mission. The acronym UAV is the most widely used term in describing a civilian pilotless aircraft.
  • Remotely Piloted Vehicle (RPV): a pilotless aircraft that is steered or controlled from a remotely located position. Manually controlled pilotless aircraft means manually controlling the aircraft position by manually adjusting its heading, altitude, and speed. In many cases, the terms UAV and RPV are interchangeably used to describe any pilotless aircraft.
  • Drone: one of the oldest terms used to describe a pilotless aircraft. A drone is defined as a pilotless aircraft controlled by radio signal. Even with the emerging of the UAV and RPV names, the name “drone” is still used even for civilian pilotless aircraft. For the purpose of this course, the word drone is used to describe a pilotless aircraft used by defense organizations.

Whether it is named a UAV, an RPV, or a drone, at a minimum, the pilotless aircraft should include the following elements:

  • Air vehicle
  • Mission planning element
  • Command and control element
  • Communication link
  • Launch and recovery element (for some of them)
  • Payload

Missions of the UAVs

Naming the different missions for UAVs is a difficult task, as there are so many possibilities and there have never been enough systems in use to explore all the possibilities. However, the two main classifications for UAV missions are the following:

  • The military mission: Military applications focus on weapons delivery and guided missile support as well as directing artillery and spotting enemy positions.
  • The civilian mission: Civilian applications of UAV are open to the imagination and only time will tell of the future missions of UAVs for civilian applications.

    As of today, civilian missions include various applications such as:

    • Security awareness
    • Disaster response, including search and support to rescuers
    • Communications and broadcast, including news/sporting event coverage
    • Cargo transport
    • Spectral and thermal analysis
    • Critical infrastructure monitoring, including power facilities, ports, and pipelines
    • Commercial photography, aerial mapping and charting, and advertising

Military and civilian missions of UAV overlap in many areas. They both use UAV for reconnaissance and surveillance. In addition, they both use UAV as a stationary platform over a point on the ground from which to perform many of the communications or remote sensing satellite functionalities with a fraction of the cost.