2: National Airspace System

Introduction

Airspace Classification

Topography

Airport Operations

Airport Markings and Signs

Collision Avoidance

Introduction

The Remote Pilot Certificate with an sUAS Rating will allow operation of an sUAS in the National Airspace System (NAS). There are two categories of airspace or airspace areas: Regulatory (Class A, B, C, D and E airspace areas, restricted, and prohibited areas) and nonregulatory (Class G airspace, Military Operations Areas, warning areas, Alert Areas, and controlled firing areas). Class A, B, C, D, and E airspace areas are referred to as controlled airspace and Class G airspace areas are referred to as uncontrolled airspace. You must become familiar with the NAS in order to safely operate with the others sharing this airspace, as well as with the nonparticipants on the ground. The following resources are critical for remote PICs to be able to understand airspace and the NAS, as well as invaluable tools for adequately planning safe operations in compliance with regulations and restrictions.

Refer to the Chart Supplement U.S. to determine what kind of airspace, ATC facilities, and traffic you can expect near the airport closest to your operations. The Chart Supplement U.S. is a publication for pilots containing key information about all airports, seaplane bases, and heliports open to the public including communications data, navigational facilities, and certain special notices and procedures. This supplement is reissued in its entirety every 56 days. See CT-8080-2, Figure 31 for a sample Chart Supplement U.S.

The aeronautical map most commonly used by manned pilots are the Sectional Aeronautical Chart and the Terminal Area Chart (TAC). Both charts include aeronautical information such as airports, airways, special use airspace, and other pertinent data. These charts are of tremendous value to the remote pilot operating an sUAS. The scale of the Sectional Aeronautical Chart is 1:500,000 (1 inch = 6.86 NM). Designed for visual navigation of slow speed aircraft in visual conditions (referred to as VFR), this chart portrays terrain relief and checkpoints such as populated places, roads, railroads, and other distinctive landmarks. These charts are revised every 6 months. See CT-8080-2, Legend 1 to become familiar with the Sectional Chart Legend, and Figure 20 on page A-4 for a sample Sectional excerpt. Information found on the TAC is similar to that found on the Sectional Chart, but at a scale of 1:250,000 (1 inch = 3.43 NM). These charts display a specific city with Class B airspace. They show more significant detail than the Sectional Chart, but have small area coverage.

NOTAMs

Notices to Air Missions (NOTAMs) provide the most current information available and can be found by visiting faa.gov, or obtained from the FAA’s Flight Service by referencing 1800wxbrief.com. They provide time-critical information on airports and changes that affect the NAS. It is necessary for the sUAS remote PIC to check for NOTAMs before each flight to determine if there are any applicable airspace restrictions.

NOTAM information is classified into five categories: NOTAM (D) or distant, Flight Data Center (FDC) NOTAMs, pointer NOTAMs, Special Activity Airspace (SAA) NOTAMs, and military NOTAMs. In addition to being available from Flight Service Stations (FSS), NOTAM (D)s are transmitted with hourly weather reports. FDC NOTAMs are issued by the National Flight Data Center (NFDC) and contain regulatory information such as temporary flight restrictions or an amendment to instrument approach procedures. Pointer NOTAMs highlight or point out another NOTAM, such as the issuance of an FDC or NOTAM (D). This type of NOTAM will assist pilots in cross-referencing important information that might not be found under an airport or NAVAID identifier. Military NOTAMs pertain to U.S. Air Force, Army, Navy, and Marine NAVAIDs/airports that are part of the NAS. SAA NOTAMs are issued when Special Activity Airspace will be active outside the published schedule times and when required by the published schedule. Pilots and other users are still responsible to check published schedule times for Special Activity Airspace as well as any NOTAMs for that airspace. NOTAM (D)s and FDC NOTAMs are contained in the Notices to Air Missions publication, which is issued every 28 days. Prior to any flight, all types of pilots must check for any NOTAMs that could affect their intended flight.

An FDC NOTAM will be issued to designate a temporary flight restriction (TFR). The NOTAM will begin with the phrase “FLIGHT RESTRICTIONS” followed by the location of the temporary restriction, effective time period, area defined in statute miles, and altitudes affected. The NOTAM will also contain the FAA coordination facility and telephone number, the reason for the restriction, and any other information deemed appropriate. TFRs are inclusive of sUAS operations; therefore it is necessary for the remote PIC to check for NOTAMs before each flight to determine if there are any applicable airspace restrictions. Common TFRs that relate to sUAS operations include, but are not limited to:

TFRs may also be found at the FAA website: tfr.faa.gov.

Other Airspace Resources

Additional resources on the subject of airspace include ACs and the AIM. ACs are issued systematically by the FAA to inform the aviation community of non-regulatory material of interest. In many cases, they are the result of a need to fully explain a particular subject (the pilot’s role in collision avoidance, for example). They are issued in a numbered-subject system corresponding to the subject areas of the Federal Aviation Regulations. ACs are available from faa.gov and are also occasionally issued in print for a fee. Some ACs include additional information on airspace. The AIM is the official guide to basic flight information and ATC procedures, which is issued yearly with ongoing revisions. These resources should be reviewed by remote PICs.

Airspace Classification

It is very important that sUAS remote PICs be aware of the type of airspace in which they will be operating their sUA. Referring to the B4UFLY app or a current aeronautical chart (faacharts.faa.gov) of the intended operating area will aid a remote PIC’s decision making regarding sUAS operations in the NAS.

Though many sUAS operations will occur in uncontrolled airspace, there are some that may need to operate in controlled airspace. Operations in what is called controlled airspace, i.e., Class B, Class C, or Class D airspace, or within the lateral boundaries of the surface area of Class E airspace designated for an airport, are not allowed unless that person has prior authorization from ATC.

The sUAS remote PIC must understand airspace classifications and requirements. The authorization process can be found at faa.gov/uas. Although sUAS will not be subject to Part 91, the equipment and communications requirements outlined in Part 91 were designed to provide safety and efficiency in controlled airspace. Accordingly, while sUAS operating under Part 107 are not subject to Part 91, as a practical matter, ATC authorization or clearance may depend on operational parameters similar to those found in Part 91. The FAA has the authority to approve or deny aircraft operations based on traffic density, controller workload, communication issues, or any other type of operations that could potentially impact the safe and expeditious flow of air traffic in that airspace. Those planning sUAS operations in controlled airspace are encouraged to contact the FAA as early as possible.

Many sUAS operations can be conducted in uncontrolled, Class G airspace without further permission or authorization. However, controlled airspace operations require prior authorization from ATC and therefore it is incumbent on the remote PIC to be aware of the type of airspace in which they will be operating their sUAS. As with other flight operations, the remote PIC should refer to current aeronautical charts and other navigation tools to determine position and related airspace.

Controlled airspace, that is, airspace within which some or all aircraft may be subject to air traffic control, consists of those areas designated as Class A, Class B, Class C, Class D, and Class E airspace. Much of the controlled airspace begins at either 700 feet or 1,200 feet above the ground. The lateral limits and floors of Class E airspace of 700 feet are defined by a magenta vignette (shading) on the Sectional Chart; while the lateral limits and floors of 1,200 feet are defined by a blue vignette on the Sectional Chart if it abuts uncontrolled airspace. Floors other than 700 feet or 1,200 feet are indicated by a number indicating the floor. See Figure 2-1.

Figure 2-1. National Airspace System: airspace classification

Class A—Class A airspace extends from 18,000 feet MSL up to and including flight level (FL) 600 (60,000 feet) and is not depicted on VFR sectional charts. No flight under VFR is authorized in Class A airspace.

Class B—Class B airspace consists of controlled airspace extending upward from the surface or higher up to specified altitudes. Class B airspace size, altitudes, and layouts vary greatly from one site to another which are centered around one or more primary airports. Each Class B airspace sector, outlined in blue on the Sectional Chart, is labeled with its delimiting arcs, radials, and altitudes. Within each segment, the floor and ceiling are denoted by one number over a second number or the letters SFC. Class B airspace is also depicted on the Terminal Area Chart; on these each Class B airspace sector is, again, outlined in blue and is labeled with its delimiting arcs, radials, and altitudes. An ATC clearance is required prior to operating within Class B airspace. Some large, very busy airports are designated as Class B Primary airports; these require the pilot hold at least a Private Pilot Certificate and may have additional operating requirements or limitations.

Class C—All Class C airspace shares the same dimensions with minor site variations. Class C is composed of two circles, both centered on the primary airport. The inner surface area has a radius of 5 NM and extends from the surface up to 4,000 feet above the airport. The “outer shelf” area has a radius of 10 NM and extends vertically from 1,200 feet AGL up to 4,000 feet above the primary airport. In addition to the Class C airspace proper, there is an outer area with a radius of 20 NM that has vertical coverage from the lower limits of the radio/radar coverage up to the top of the approach control facility’s delegated airspace. Within the outer area, pilots are encouraged to participate but it is not a requirement. Class C airspace service to aircraft proceeding to a satellite airport is terminated at a sufficient distance to allow time to change to the appropriate tower or advisory frequency. On aeronautical charts, Class C airspace is depicted by solid magenta lines. Class C requires two-way radio communications equipment, a transponder, and an encoding altimeter.

Class D—Class D airspace extends upward from the surface to approximately 2,500 feet AGL (the actual height is as needed). Class D airspace may include one or more airports and is normally 4 NM in radius centered around a designated airport. The actual size and shape is depicted on sectional charts by a blue dashed line and numbers showing the top or airspace ceiling. When the ceiling of Class D airspace is less than 1,000 feet and/or the visibility is less than 3 statute miles, additional restrictions exist for manned aircraft and may preclude UAS operations; contact ATC for information during these circumstances.

Class E—Magenta shading on the Sectional Chart identifies Class E airspace starting at 700 feet AGL, and no shading (or blue if next to Class G airspace) identifies Class E airspace starting at 1,200 feet AGL. It may also start at other altitudes. All airspace from 14,500 feet to 17,999 feet and airspace above 60,000 feet is Class E airspace. It also includes the surface area of some airports with an instrument approach but no control tower. An airway is a corridor of Class E airspace extending from 1,200 feet above the surface (or as designated) up to and including 17,999 feet MSL, and 4 NM either side of the centerline. The airway is indicated by a centerline, shown in blue.

Class G—Class G airspace is airspace within which ATC has neither the authority nor responsibility to exercise any control over air traffic. Class G airspace typically extends from the surface to the base of the overlying controlled (Class E) airspace, which is normally 700 or 1,200 feet AGL. In some areas of the western U.S. and Alaska, Class G airspace may extend from the surface to 14,500 feet MSL. An exception to this rule occurs when 14,500 feet MSL is lower than 1,500 feet AGL.

Prohibited Areas are blocks of airspace within which the flight of aircraft is prohibited. Examples include the airspace around the White House and the U.S. Capitol building.

Restricted Areas denote the presence of unusual, often invisible, hazards to aircraft such as artillery firing, aerial gunnery, or guided missiles. Penetration of restricted areas without authorization of the using or controlling agency may be extremely hazardous to the aircraft and its occupants. Per Part 107, entry into restricted airspace is not authorized without permission from the controlling agency.

Warning Areas contain the same hazardous activities as those found in restricted areas, but are located in international airspace. Prohibited, restricted, or warning areas are depicted as shown in CT-8080-2, Legend 1.

Alert Areas may contain a high volume of pilot training activities or an unusual type of aerial activity. Pilots should be particularly alert when flying in these areas. Pilots of participating aircraft as well as pilots transiting the area are equally responsible for collision avoidance.

Military Operations Areas (MOAs) consist of airspace established for the purpose of separating certain military training activities from IFR traffic. Pilots should exercise extreme caution while flying within an active MOA. Prior to entering an active MOA, pilots should contact the controlling agency for traffic advisories.

Military Training Routes (MTRs) have been developed for use by the military for the purpose of conducting low-altitude, high-speed training. Generally, MTRs are established below 10,000 feet MSL for operations at speeds in excess of 250 knots. IFR Military Training Route (IR) operations are conducted in accordance with instrument flight rules, regardless of weather conditions. VFR Military Training Routes (VR) operations are conducted in accordance with visual flight rules. IR and VR at and below 1,500 feet AGL (with no segment above 1,500) will be identified by four digit numbers, e.g., VR1351, IR1007. IR and VR with one or more segments above 1,500 feet AGL (routes can be above or below 1,500 feet AGL) will be identified by three digit numbers, e.g., IR341, VR426. The lateral boundaries of MTRs vary. For more information, pilots should consult the Department of Defense Flight Information Publication (FLIP).

Advisory Circular 91-36, Visual Flight Rules (VFR) Flight Near Noise-Sensitive Areas, defines the surface of a National Park area (including parks, forests, primitive areas, wilderness areas, recreational areas, National Seashores, National Monuments, National Lakeshores, and National Wildlife Refuge and Range Areas) as: the highest terrain within 2,000 feet laterally of the route of flight, or the upper-most rim of a canyon or valley. These are marked on sectional charts with a solid blue line on the outside of the area border with blue dots on the inside of the border line. Aircraft are requested to remain at least 2,000 feet above the surface of National Parks, National Monuments, Wilderness and Primitive Areas, and National Wildlife Refuges.

Local Airport Advisory (LAA) is an advisory service provided by Flight Service facilities, which are located on the landing airport, using a discrete ground-to-air frequency or the tower frequency when the tower is closed. LAA services include local airport advisories, automated weather reporting with voice broadcasting, and a continuous Automated Surface Observing System (ASOS)/Automated Weather Observing Station (AWOS) data display, other continuous direct reading instruments, or manual observations available to the specialist.

When ATC authorization is required (at or near an airport with a control tower and/or when operating within controlled airspace), it must be requested and granted before any operation in that airspace. There is currently no established timeline for approval after ATC permission has been requested because the time required for approval will vary based on the resources available at the ATC facility and the complexity and safety issues raised by each specific request. For this reason, remote PICs should contact the appropriate ATC facility as soon as possible prior to any operation in Class B, C and D airspace and within the lateral boundaries of the surface area of Class E airspace designated for an airport. ATC has the authority to approve or deny aircraft operations based on traffic density, controller workload, communication issues, or any other type of operations that could potentially impact the safe and expeditious flow of air traffic in that airspace.

When ATC authorization is not required (at or near an airport without a control tower and/or when operating within uncontrolled airspace), remote pilots should monitor the Common Traffic Advisory Frequency (CTAF) of any nearby airport(s) to stay aware of manned aircraft communications and operations. The CTAF can be found in the Chart Supplement U.S. and on Sectional and Terminal Area Charts (noted by a magenta “C” next to the frequency).

Topography

To identify a point on the surface of the earth, a geographic coordinate, or grid, system was devised. By reference to meridians of longitude and parallels of latitude, any position may be accurately located when using the grid system.

Equidistant from the poles is an imaginary circle called the equator. The lines running east and west, parallel to the equator are called parallels of latitude, and are used to measure angular distance north or south of the equator. From the equator to either pole is 90°, with 0° being at the equator, while 90° north latitude describes the location of the North Pole. See Figure 2-2. Lines called meridians of longitude are drawn from pole to pole at right angles to the equator. The prime meridian, used as the zero degree line, passes through Greenwich, England. From this line, measurements are made in degrees both easterly and westerly up to 180°.

Figure 2-2. Meridians of longitude and parallels of latitude

Any specific geographical point can be located by reference to its longitude and latitude. For example, Washington, DC, is approximately 39° north of the equator and 77° west of the prime meridian and would be stated as 39°N 77°W. Note that latitude is stated first.

A Sectional Chart is a pictorial representation of a portion of the Earth’s surface upon which lines and symbols in a variety of colors represent features and/or details that can be seen on the Earth’s surface. Contour lines, shaded relief, color tints, obstruction symbols, and maximum elevation figures are all used to show topographical information. Explanations and examples may be found in the chart legend. Remote pilots should become familiar with all of the information provided in each Sectional Chart Legend, found in Legend 1 in the CT-8080-2.

In order to describe a location more precisely, each degree (°) is subdivided into 60 minutes (') and each minute further divided into 60 seconds ("), although seconds are not shown. Thus, the location of the airport at Elk City, Oklahoma is described as being at 35°25'55"N 99°23'15"W (35 degrees, 25 minutes, 55 seconds north latitude; 99 degrees, 23 minutes, 15 seconds west longitude). Degrees of west longitude increase moving west from the prime meridian until reaching the international line and degrees of east longitude increase moving east from the prime meridian to the international date line. Degrees of north latitude increase moving north from the equater to the north pole and degrees of south latitude increase moving south from the equator to the south pole.

Airport Operations

When operating in the vicinity of an airport, the remote PIC must be aware of all traffic patterns and approach corridors to runways and landing areas. Sources for this airport data include the Sectional Chart and the Chart Supplement U.S. The remote PIC must avoid operating anywhere that the presence of the sUAS may interfere with airport operations, such as approach corridors, taxiways, runways, or helipads. Furthermore, the remote PIC must yield right-of-way to all other aircraft, including aircraft operating on the surface of the airport.

Remote PICs are prohibited from operating their sUA in a manner that interferes with operations and traffic patterns at airports, heliports, and seaplane bases. While a sUA must always yield right-of-way to a manned aircraft, a manned aircraft may alter its flightpath, delay its landing, or take off in order to avoid an sUAS that may present a potential conflict or otherwise affect the safe outcome of the flight. For example, an sUA hovering 200 feet above a runway may cause a manned aircraft holding short of the runway to delay takeoff, or a manned aircraft on the downwind leg of the pattern to delay landing. While the sUA in this scenario would not pose an immediate traffic conflict to the aircraft on the downwind leg of the traffic pattern or to the aircraft intending to take off, nor would it violate the right-of-way rules, the sUA would nevertheless have interfered with the operations of the traffic pattern at an airport.

ATC towers are established to promote the safe, orderly, and expeditious flow of air traffic. The tower controller will issue instructions for aircraft to follow the desired flight path while in the airport traffic area whenever necessary by using terminology as shown in Figure 2-3. Manned aircraft use this same terminology to self-announce position and intentions, consistent with recommended traffic advisory procedures.

Figure 2-3. Manned aircraft traffic pattern.

In order to avoid interfering with operations in a traffic pattern, remote PICs should avoid operating in the traffic pattern or published approach corridors used by manned aircraft. When operational necessity requires the remote PIC to operate at an airport in uncontrolled airspace, the remote PIC should operate the sUA in such a way that the manned aircraft pilot does not need to alter his or her flightpath in the traffic pattern or on a published instrument approach in order to avoid a potential collision. Because remote PICs have an obligation to yield right-of-way to all other aircraft and avoid interfering in traffic pattern operations, the FAA expects that most remote PICs will avoid operating in the vicinity of airports because their aircraft generally do not require airport infrastructure, and the concentration of other aircraft increases in the vicinity of airports.

The FAA has the authority to approve or deny aircraft operations based on traffic density, controller workload, communication issues, or any other type of operations that could potentially impact the safe and expeditious flow of air traffic in that airspace. Those planning sUAS operations in controlled airspace are encouraged to contact the FAA as early as possible.

When ATC authorization is required (at or near an airport with a control tower and/or when operating within controlled airspace), it must be requested and granted before any operation in that airspace. The time required for approval will vary based on the resources available at the ATC facility and the complexity and safety issues raised by each specific request. For this reason, remote PICs should contact the appropriate ATC facility as soon as possible prior to any operation in Class B, C, and D airspace and within the lateral boundaries of the surface area of Class E airspace designated for an airport.

When ATC authorization is not required (at or near an airport without a control tower and/or when operating within uncontrolled airspace), remote pilots should monitor the CTAF to stay aware of manned aircraft communications and operations. For the sake of safety, it is advisable for remote PICs to announce their sUAS activity on the CTAF to make manned pilots aware of such operations.

For recurring or long-term operations in a given location, prior authorization could include a Letter of Agreement (LOA), established with the controlling ATC facility for that airspace, to establish sUAS operating procedures. This LOA will outline the ability to integrate into the existing air traffic operation and may improve the likelihood of access to the airspace where operations are proposed. This agreement will ensure all parties involved are aware of limitations and conditions and will enable the safe flow of aircraft operations in that airspace. For short-term or short-notice operations proposed in controlled airport airspace, an LOA may not be feasible. Prior authorization is required in all cases.

All areas on-airport that are used for certain cargo and passenger functions, including screening, must be a Security Identification Display Area (SIDA). A SIDA is that portion of an airport within the United States, specified in the security program, in which individuals must display an airport-issued or approved identification and carry out other security measures.

Airport Markings and Signs

Remote pilots need to be familiar with standard airport markings and signs to exercise vigilant collision avoidance, practice sound see-and-avoid procedures, and not interfere with manned aircraft operations.

Runway numbers and letters are determined from the approach direction. The number is the magnetic heading of the runway rounded to the nearest 10°. For example, a runway facing an azimuth of 183° would result in a runway number of 18; a runway with a magnetic azimuth of 076° would result in a runway numbered 8. If there is more than one runway facing the same direction, the runway will have letters to differentiate between left (L), right (R), or center (C). See Figure 2-4.

Figure 2-4. Runway numbers and letters

The designated beginning of the runway that is available and suitable for the landing of aircraft is called the threshold (Figure 2-5a). A threshold that is not at the beginning of the full-strength runway pavement is a displaced threshold. The paved area behind the displaced threshold is marked by arrows (Figure 2-5b) and is available for taxiing, takeoff, and landing rollout, but is not to be used for landing, usually because of an obstruction in the approach path. See Figure 2-5.

Figure 2-5. Threshold marking

Stopways are found extending beyond some usable runways. These areas are marked by chevrons, and while they appear usable, they are suitable only as overrun areas. See Figure 2-6.

Figure 2-6. Stopway marking

A closed runway which is unusable for various reasons and may be hazardous, even though it may appear usable, will be marked by an “X.”

A basic runway may only have centerline markings and runway numbers. Airports supporting instrument operations, higher volumes, and larger aircraft may use additional runway markings. See Figure 2-7.

Figure 2-7. Selected airport markings and surface lighting

Aircraft use taxiways to transition from parking areas to the runway. Taxiways are identified by a continuous yellow centerline stripe and may include edge markings to define the edge of the taxiway. Where a taxiway approaches a runway, there may be a holding position marker. These consist of four yellow lines (two solid and two dashed). The solid lines are where the aircraft is to hold. Beyond this point, an aircraft is considered to be on the runway.

There are six types of signs that may be found at airports. See Figure 2-8. The more complex the layout of an airport, the more important the signs become to pilots. The six types of signs are:

Figure 2-8. Airport signs

Collision Avoidance

A key component to avoiding both manned and unmanned aircraft is active collision avoidance procedures. Scanning the sky for other aircraft is a critical factor in collision avoidance. Remote pilots and visual observers must develop an effective scanning technique that maximizes visual capabilities. Because the eyes focus only on a narrow viewing area, effective scanning is accomplished with a series of short, regularly spaced eye movements. Each movement should not exceed 10°, and each area should be observed for at least one second. Any aircraft that appears to have no relative motion and stays in one scan quadrant is likely to be on a collision course. If a target shows neither lateral nor vertical motion, but increases in size, take evasive action.

Another critical component to collision avoidance is avoiding operations near and under moored balloons and helicopters. The helicopter community performs their critical operations typically at 1,000 feet or less and often in a wire/obstruction rich environment. It is important to note that not all wires are marked.

Inflight Hazards

Although most sUAS cannot be operated in precipitation or other adverse weather conditions, remote PICs should be aware that static electricity buildup (sometimes referred to as P-static) can occur when an aircraft in flight comes in contact with rain, snow, fog, sleet, hail, volcanic ash, dust; any solid or liquid particles. In a very short period of time a substantial negative charge will develop on the skin of the aircraft. If the aircraft is not equipped with static dischargers, or has an ineffective static discharger system, when a sufficient negative voltage level is reached the aircraft may develop a phenomenon called a “corona,” a luminous manifestation of the static electricity accumulation. Such buildups may discharge from the extremities of the aircraft, such as the wing tips, horizontal stabilizer, vertical stabilizer, antenna, propeller tips, etc. The visible discharge of static electricity is referred to as “St. Elmo’s fire.” P-static can also disrupt communications between the sUAS and the control station which may have significant detrimental impact on the ability to control or retrieve the sUAS. Some sUAS may use static dischargers to address this problem.

In recent years, the use of lasers has had more of an impact on all types of flight operations. Of concern to NAS users are those laser events that may affect pilots, e.g., outdoor laser light shows or demonstrations for entertainment and advertisements at special events and theme parks. Generally, the beams from these events appear as bright blue-green in color; however, they may be red, yellow, or white, and some laser systems produce light that is invisible to the human eye. FAA regulations prohibit the disruption of aviation activity by any person on the ground or in the air.

Remote pilots should be aware that illumination from these laser operations are able to create temporary vision impairment miles from the actual location. In addition, these operations can cause permanent eye damage. Remote pilots should therefore use caution when using sUAS in and around known laser activity. Extreme caution should be exercised if an sUAS is fitted with a laser as it could potentially cause hazards to manned aircraft, the public, or even the remote PIC or other crewmembers. Pilots should make themselves aware of where these activities are being conducted and avoid these areas if possible. When these activities become known to the FAA, NOTAMs are issued to inform the aviation community of the events. Pilots should consult NOTAMs or the Special Notices section of the Chart Supplement U.S. for information regarding these activities.

Although remote pilots should typically avoid operations in and around power plants, industrial production facilities, or other industrial systems, there may be times when such activity is sanctioned by the owners of these facilities for inspection or imaging. These types of locations often have thermal plumes, which are visible or invisible emissions of large amounts of vertically directed unstable gases. High temperature exhaust plumes may cause significant air disturbances such as turbulence and vertical shear. Other identified potential hazards include, but are not necessarily limited to, reduced visibility, oxygen depletion, engine particulate contamination, exposure to gaseous oxides, and/or icing. Results of encountering a plume may include airframe damage, aircraft upset, and/or engine damage/failure. These conditions could quickly lead to damage and/or loss of control of an sUAS. These hazards are most critical during low altitude flight, especially during maneuvering, takeoff and landing. When able, a pilot should fly upwind of possible thermal plumes. When a plume is visible via smoke or a condensation cloud, remain clear yet at the same time, realize that a plume may have both visible and invisible characteristics. Remote pilots are encouraged to exercise caution when operating in the vicinity of thermal plumes. Refer to the Chart Supplement U.S., where the airport amplifying notes may warn pilots and identify the location of structure(s) emitting thermal plumes.

Most skeletal structures are supported by guy wires, which are very difficult to see in good weather and can be invisible at dusk or during periods of reduced visibility. These wires can extend about 1,500 feet horizontally from a structure; therefore, all skeletal structures should be avoided horizontally by at least 2,000 feet.

Birds and wildlife pose a particular threat to aircraft operations. Although catastrophic events are rare in manned aviation, sUAS are particularly vulnerable to such events. Collision with wildlife will likely cause significant damage and/or loss of control. Remote pilots should report collisions between aircraft and wildlife to assist in the tracking of these incidents and to potentially take action to mitigate future risks of these events. Reports may be sent to the FAA via their Wildlife Strike Report system (wildlife.faa.gov/strikenew.aspx). Many airports advise pilots of other wildlife hazards through the Chart Supplement U.S. and the NOTAM system.

Collisions between aircraft and animals have been increasing and are not limited to rural airports, as these accidents have also occurred at several major airports. Pilots should exercise extreme caution when warned of the presence of wildlife on and in the vicinity of airports. If you observe birds, deer, or other large animals in close proximity to movement areas, advise the FSS, tower, or airport management. Remote pilots should be aware of bird activity in proximity to their area of operation. It is well documented that some types of birds are agitated by sUAS and may even attack such aircraft. Also, it has been shown that sUAS activity and noise may disturb certain types of wildlife; therefore remote pilots should be cognizant of the potential impact of their operations on the local environment. Many states are considering passing legislation to restrict sUAS operations that may disturb wildlife.

[10-2024]