Introduction to UAV Systems. Mohammad H. Sadraey

frequency bands are employed by the Global Hawk?

      82 Briefly describe: (a) line‐of‐sight (LOS) and (b) beyond line‐of‐sight (BLOS) communications for the Global Hawk.

      83 Briefly describe the major setback during flight testing of the Global Hawk.

      84 What was the reason behind the mishap for the Global Hawk in the December 1999 flight?

      85 Why were two Global Hawk prototype air vehicles lost during the deployment phase in 2002 and 2003? Explain.

      86 Why was a Global Hawk lost on June 20, 2019?

      87 Briefly describe the unconventional development cycle of the Predator during the 1980s.

      88 An advanced version of what aircraft was designated as RQ‐1 Predator in the early 1990s?

      89 What UAV attempted an air‐to‐air engagement with an Iraqi MiG‐25 in 2002?

      90 When was the Predator UAV retired?

      91 Briefly compare the primary differences between the Predator and the Reaper.

      92 Compare the main difference between configurations of the Predator and the Reaper.

      93 When was the first operational mission of the MQ‐9 Reaper?

      94 What are the payloads of the MQ‐9 Reaper?

      95 Briefly describe the characteristics of GCS of the MQ‐9 Reaper.

      96 What is the type of propulsion system for the MQ‐9 Reaper?

      97 Write: (a) maximum takeoff mass, (b) wingspan, and (c) engine Power of the MQ‐9 Reaper.

      98 Write: (a) maximum speed, (b) range, (c) endurance, and (d) ceiling of the MQ‐9 Reaper.

      99 List the dominant US UAV manufacturers.

      100 Briefly discuss the ethical concerns of UAVs.

      101 What is the mission of the Swift HALE UAV?

      102 Name three recent UAV projects with a pseudo‐satellite mission.

      Note

      1 1 https://www.modelaircraft.org

2 Classes and Missions of UAVs

      2.1 Overview

This chapter provides general classes and missions of Unmanned Aerial Vehicles (UAV). It also describes a representative sample of unmanned aerial systems (UAS), including some of the earlier designs that had a large impact on current systems. The range of UAS sizes and types now runs from air vehicles (AVs) small enough to land on the palm of your hand to large lighter‐than‐air vehicles. This chapter mainly concentrates on those in the range from model¹ airplanes up to medium‐sized aircraft, as does the rest of this book, where “unmanned aerial systems” and “UAV Systems” are utilized interchangeably.

      Much of the early development of UAS was driven by government and military requirements, and the bureaucracies that manage such programs have made repeated efforts to establish a standard terminology for describing various types of UAS in terms of the capabilities of the air vehicles. While the “standard” terminology constantly evolves and occasionally changes abruptly, some of it has come into general use in the UAV community and is briefly described.

      Finally, the chapter also attempts to summarize the applications for which UAS have been or are being considered, which provides a context for the system requirements that drive the design tradeoffs that are the primary topic of this book.

2.2 Classes of UAV Systems

      2.2.1 Classification Criteria

There are a number of criteria for classification of UAVs. It is convenient to have a generally agreed upon scheme for classifying UAVs rather like the classification of military aircraft in general into such classes as transport, observation, fighter, attack, cargo, and so on. Table 2.1 provides some criteria for classification of UAVs, and their related classes.

Parts 48 and 107 of FAR regulate the application of small UAVs. For instance, you may not operate an sUAS at night, which is defined in the US (except Alaska) as the time between the end of evening civil twilight and beginning of morning civil twilight. This is due to the fact that, at night, there is no sufficient visibility to the remote pilot. A small unmanned aircraft is defined as an unmanned aircraft weighing more than 0.55 lb and less than 55 pounds on takeoff, including everything that is on board or otherwise attached to the aircraft.

Table 2.1 Criteria for classification of UAVs

No.	Classification Criterion	Class
1	Manufacturing location	1. Home‐made (Model), 2. Industrial
2	User	1. Civil, 2. Military
3	Mission	1. Filming, 2. Package delivery, 3. Intelligence, Surveillance, and Reconnaissance (ISR), 4. Precision strike, 5. Combat (UCAV), 6. Teaming, 7. Meteorological measurements, 8. High‐altitude platform, 9. Search and observation
4	Size	1. Micro, 2. Mini, 3. Very small, 4. Small, 5. Medium, 6. Large
5	Wing configuration	1. Fixed‐wing, 2. Rotary‐wing (includes multi‐copter), 3. Hybrid
6	FAA [5]	Small UAVs (under FAR Parts 48 and 107)
7	Altitude/Range/Endurance	1. Very low‐cost close range, 2. Close range, 3. Short range, 4. Mid‐range, 5. Long range, 6. Medium‐altitude, long endurance (MALE), 7. High‐altitude, long endurance (HALE)
8	Number of uses	1. Reusable, 2. Expendable

      In the following sections, three specific classifications based on: (1) range and endurance, (2) mission, and (3) tier (for US Air Force, Marine Corps, and Army) are presented.

      2.2.2 Classification by Range and Endurance

      Shortly after being appointed the central manager of US military UAV programs, the Joint UAV Program Office (JPO) defined classes of UAVs as a step toward providing some measure of standardization to UAV terminology. They were:

       Very Low‐Cost, Close‐Range: Required by the Marine Corps and perhaps the Army to have a range of about 5 km (3 miles) and cost about $10,000 per air vehicle. This UAV system fits into what could be called the “model airplane” type of system and its feasibility with regard to both performance and cost had not been proven but since has been demonstrated by systems such as the Raven and Dragon Eye.

       Close Range: Required by all of the services but its concept of operation varied greatly depending on the service. The