Task B. Airspace Operational Requirements

UA.II.B.K1  Basic weather minimums (AC 107-2A)

5.12.3 Visibility and Distance from Clouds.

The remote PIC must determine that the visibility from the CS is at least 3 sm and that the small unmanned aircraft maintains at least 500 feet below clouds and at least 2,000 feet horizontally from clouds. Obtaining local aviation weather reports that include current and forecast weather conditions is one means of determining visibility and cloud clearance. If there is more than one local aviation reporting station near the operating area, the remote PIC should choose the closest one that is most representative of the terrain surrounding the operating area. If local aviation weather reports are not available, the remote PIC cannot operate the small unmanned aircraft until he or she is able to determine the required visibility and cloud clearances by other reliable means. The small unmanned aircraft cannot be operated above any cloud, and there cannot be obstructions to visibility, such as smoke or a cloud, between the small unmanned aircraft and the remote PIC (§ 107.39).

UA.II.B.K2  ATC authorizations and related operating limitations (AC 107-2A)

5.10 Operation Near Airports, in Certain Airspace, in Prohibited or Restricted Areas, or in the Proximity of Certain Areas Designated by a Notice to Airmen (NOTAM).

Small unmanned aircraft may operate in controlled or uncontrolled airspace. Operations in 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 permitted unless that person has prior authorization from air traffic control (ATC) (§ 107.41). Information concerning the current authorization process is available at https://www.faa.gov/uas/. The remote PIC must understand airspace classifications and requirements. Failure to do so could be contrary to part 107 regulations and may potentially have an adverse effect on the safety of operations. Small UAS operating under part 107 may not be subject to part 91 requirements, because the equipage and communications requirements outlined in part 91 were designed to provide safety and efficiency in the National Airspace System (NAS). ATC authorizations 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 operation that could potentially impact the safe and expeditious flow of air traffic in that airspace.

5.12 Operating Limitations for Small Unmanned Aircraft.

Operations of the small unmanned aircraft must comply with the following limitations:

• Cannot be flown faster than a groundspeed of 87 knots (100 miles per hour (mph));

• Cannot be flown higher than 400 feet above ground level (AGL), unless flown within a 400-foot radius of a structure and does not fly higher than 400 feet above the structure’s immediate uppermost limit;

• Minimum visibility, as observed from the location of the CS, may not be less than 3 sm; and

• Minimum distance from clouds being no less than 500 feet below a cloud and no less than 2,000 feet horizontally from the cloud (§ 107.51).

Note: These operating limitations are intended, among other things, to support the remote pilot’s ability to identify hazardous conditions relating to encroaching aircraft or persons on the ground, and to take appropriate actions to maintain safety.

5.12.1 Determining Groundspeed. Many different types of small unmanned aircraft and different ways to determine groundspeed exist. This guidance will only touch on some of the possible means for the remote PIC to ensure the small unmanned aircraft does not exceed a groundspeed of 87 knots during flight operations. Examples of methods to ensure compliance with this limitation are:

• Installing a Global Positioning System (GPS) device on the small unmanned aircraft that reports groundspeed information to the remote pilot, allowing the remote pilot to determine the wind direction and speed and calculate the small unmanned aircraft airspeed for a given direction of flight;

• Timing the groundspeed of the small unmanned aircraft when it is flown between two or more fixed points, considering wind speed and direction between each point, then noting the power settings of the small unmanned aircraft to operate at or less than 87 knots groundspeed; or

• Using the small unmanned aircraft’s manufacturer design limitations (e.g., installed groundspeed limiters).

5.12.2 Determining Altitude. In order to comply with the maximum altitude requirements of part 107, a remote pilot may determine altitude by:

• Installing a calibrated altitude reporting device on the small unmanned aircraft that reports the small unmanned aircraft altitude above mean sea level (MSL) to the remote pilot, who subtracts the MSL elevation of the CS from the small unmanned aircraft reported MSL altitude to determine the small unmanned aircraft AGL altitude above the terrain or structure;

• Installing a GPS device on the small unmanned aircraft that has the capability of reporting MSL altitude to the remote pilot;

• Having the remote pilot and VO pace off 400 feet from the small unmanned aircraft while it is on the ground to get a visual perspective of distance so that the remote pilot and VO can recognize and maintain that visual perspective (or closer) when the small unmanned aircraft is in flight; or

• Using the known height of local rising terrain and/or structures as a reference.

UA.II.B.K3  Operations near airports (AC 107-2A)

5.10.1 Small Unmanned Aircraft Operations Near an Airport—Notification and Permissions.

Unless the flight is conducted within controlled airspace, no notification or authorization is necessary to operate a small unmanned aircraft at or near an airport. When operating in the vicinity of an airport, the remote PIC must be aware of and avoid all traffic patterns and approach corridors to runways and landing areas. The remote PIC must avoid operating in any area in which the presence of the small UAS may interfere with operations at the airport, such as approach corridors, taxiways, runways, or helipads (§ 107.43). The remote PIC must yield right-of-way to all other aircraft, including aircraft operating on the surface of the airport (§ 107.43).

5.10.1.1  Remote PICs are prohibited from operating a small unmanned aircraft in a manner that interferes with operations and traffic patterns at airports, heliports, and seaplane bases (§ 107.43). Small unmanned aircraft 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 a small unmanned aircraft that may present a potential conflict or otherwise affect the safe outcome of the flight. A small unmanned aircraft 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 small unmanned aircraft in this scenario would not present 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 provision of § 107.37(a), the small unmanned aircraft would have interfered with the operations of the traffic pattern at an airport.

5.10.1.2  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 small unmanned aircraft 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.

5.10.2 Air Traffic Organization (ATO).

When receiving requests for authorization to operate in controlled airspace, ATO does not approve or deny small unmanned aircraft operations on the basis of equipage that exceeds the part 107 requirements. Additional equipage and technologies, such as geo-fencing, have not been certificated by the FAA and need to be examined on a case-by-case basis in order for the FAA to determine their reliability and functionality. Additionally, requiring staff from ATO to review equipage would place a burden on ATO and detract from other duties. Instead of seeking an authorization, a remote pilot who wishes to operate in controlled airspace because the remote pilot can demonstrate mitigations through equipage may do so by applying for a CoW.

5.13 Remaining Clear of Other Aircraft.

A remote PIC has a responsibility to operate the small unmanned aircraft so that it remains clear of and yields to all other aircraft (§ 107.37). This is traditionally referred to as “see and avoid.” To satisfy this responsibility, the remote PIC must know the location and flightpath of his or her small unmanned aircraft at all times. The remote PIC must be aware of other aircraft, persons, and property in the vicinity of the operating area, and maneuver the small unmanned aircraft to avoid collision. The remote PIC must take action to ensure other aircraft will not need to maneuver to avoid colliding with the small unmanned aircraft.

UA.II.B.K4  Potential flight hazards (AIM 7-6-4)

Obstructions To Flight

a. General. Many structures exist that could significantly affect the safety of your flight when operating below 500 feet above ground level (AGL), and particularly below 200 feet AGL. While 14 CFR Part 91.119 allows flight below 500 feet AGL when over sparsely populated areas or open water, such operations involve increased safety risks. At and below 200 feet AGL there are numerous power lines, antenna towers, etc., that are not marked and lighted and/or charted as obstructions and, therefore, may not be seen in time to avoid a collision. Notices to Air Missions NOTAMs are issued on those lighted structures experiencing temporary light outages. However, some time may pass before the FAA is notified of these outages, and the NOTAMs issued, thus pilot vigilance is imperative. Additionally, new obstructions may not be on current charts because the information was not received prior to the FAA publishing the chart.

b. Antenna Towers. Extreme caution should be exercised when flying less than 2,000 feet AGL because of numerous skeletal structures, such as radio and television antenna towers, that exceed 1,000 feet AGL with some extending higher than 2,000 feet AGL. 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.

c. Overhead Wires. Overhead transmission and utility lines often span approaches to runways, natural flyways such as lakes, rivers, gorges, and canyons, and cross other landmarks pilots frequently follow such as highways, railroad tracks, etc. As with antenna towers, these power transmission and/or utility lines and the supporting structures of these lines may not always be readily visible. The wires may be virtually impossible to see under certain conditions. Spherical markers may be used to identify overhead wires and catenary transmission lines and may be lighted. In some locations, the supporting structures of overhead transmission lines are equipped with unique sequence flashing white strobe light systems to indicate that there are wires between the structures. The flash sequence for the wire support structures will be middle, top, and bottom with all lights on the same level flashing simultaneously. However, not all power transmission and/or utility lines require notice to the FAA as they do not exceed 200 feet AGL or meet the obstruction standard of 14 CFR Part 77 and, therefore, are not marked and/or lighted. All pilots are cautioned to remain extremely vigilant for power transmission and/or utility lines and their supporting structures when following natural flyways or during the approach and landing phase. This is particularly important for seaplane and/or float equipped aircraft when landing on, or departing from, unfamiliar lakes or rivers.

d. Wind Turbines. The number, size, and height of individual wind turbines and wind turbine farms have increased over time. The locations of wind turbine farms have also expanded to areas more commonly flown by VFR pilots and to all regions of the United States. VFR pilots should be aware that many wind turbines are exceeding 499 feet AGL in height, which may affect minimum safe VFR altitudes in uncontrolled airspace. In addition, many wind turbines are encroaching on the 700 foot AGL floor of controlled airspace (Class E). Pilots are cautioned to maintain appropriate safe distance (laterally, vertically, or both). Wind turbines are typically charted on Visual Flight Rules (VFR) Sectional Charts and/or Terminal Area Charts. For a description of how wind turbines and wind turbine farms are charted, refer to the FAA Aeronautical Chart User’s Guide. Wind turbines are normally painted white or light gray to improve daytime conspicuity. They are typically lit with medium-intensity, flashing red lights, placed as high as possible on the turbine nacelle (not the blade tips), that should be synchronized to flash together; however, not all wind turbine units within a farm need to be lighted, depending on their location and height. Sometimes, only the perimeter of the wind turbine farm and an arrangement of interior wind turbines are lit. Some wind turbine farms use Aircraft Detection Lighting Systems (ADLS), which are proximity sensor-based systems designed to detect aircraft as they approach the obstruction. This system automatically activates the appropriate obstruction lights until they are no longer needed based on the position of the transiting aircraft. This technology reduces the impact of nighttime lighting on nearby communities and migratory birds and extends the life expectancy of the obstruction lights. For more information on how obstructions such as wind turbines are marked and lighted, refer to Advisory Circular 70/7460-1, Obstruction Marking and Lighting. Pilots should be aware that wind turbines in motion could result in limitations of air traffic services in the vicinity of the wind turbine farms.

e. Meteorological (MET) Evaluation Towers. MET towers are used by wind energy companies to determine feasible sites for wind turbines. Some of these towers are less than 200 feet AGL. These structures are portable, erected in a matter of hours, installed with guyed wires, and constructed from a galvanized material often making them difficult to see in certain atmospheric conditions. Markings for these towers include alternating bands of aviation orange and white paint, and high-visibility sleeves installed on the outer guy wires. However, not all MET towers follow these guidelines, and pilots should be vigilant when flying at low altitude in remote or rural areas.

f. Other Objects/Structures. There are other objects or structures that could adversely affect your flight such as temporary construction cranes near an airport, newly constructed buildings, new towers, etc. Many of these structures do not meet charting requirements or may not yet be charted because of the charting cycle. Some structures do not require obstruction marking and/or lighting, and some may not be marked and lighted even though the FAA recommended it. VFR pilots should carefully review NOTAMS for temporary or permanent obstructions along the planned route of flight during their preflight preparations. Particular emphasis should be given to obstructions in the vicinity of the approach and departure ends of the runway complex or any other areas where flight below 500 feet AGL is planned or likely to occur.

UA.II.B.K4a  Common aircraft accident causal factors (AIM)

7-6-1 Accident Cause Factors

a.  The 10 most frequent cause factors for general aviation accidents that involve the pilot‐in‐command are:

1. 1. Inadequate preflight preparation and/or planning.
   2. Failure to obtain and/or maintain flying speed.
   3. Failure to maintain direction control.
   4. Improper level off.
   5. Failure to see and avoid objects or obstructions.
   6. Mismanagement of fuel.
   7. Improper inflight decisions or planning.
   8. Misjudgment of distance and speed.
   9. Selection of unsuitable terrain.
   10. Improper operation of flight controls.

b.  This list remains relatively stable and points out the need for continued refresher training to establish a higher level of flight proficiency for all pilots. A part of the FAA’s continuing effort to promote increased aviation safety is the Aviation Safety Program. For information on Aviation Safety Program activities contact your nearest Flight Standards District Office.

c.  Alertness. Be alert at all times, especially when the weather is good. Most pilots pay attention to business when they are operating in full IFR weather conditions, but strangely, air collisions almost invariably have occurred under ideal weather conditions. Unlimited visibility appears to encourage a sense of security which is not at all justified. Considerable information of value may be obtained by listening to advisories being issued in the terminal area, even though controller workload may prevent a pilot from obtaining individual service.

d. Giving Way. If you think another aircraft is too close to you, give way instead of waiting for the other pilot to respect the right‐of‐way to which you may be entitled. It is a lot safer to pursue the right‐of‐way angle after you have completed your flight.

UA.II.B.K4b  Avoid flight beneath unmanned balloons (AIM)

7-6-5  Avoid Flight Beneath Unmanned Balloons

a.  The majority of unmanned free balloons currently being operated have, extending below them, either a suspension device to which the payload or instrument package is attached, or a trailing wire antenna, or both. In many instances these balloon subsystems may be invisible to the pilot until the aircraft is close to the balloon, thereby creating a potentially dangerous situation. Therefore, good judgment on the part of the pilot dictates that aircraft should remain well clear of all unmanned free balloons and flight below them should be avoided at all times.

b.  Pilots are urged to report any unmanned free balloons sighted to the nearest FAA ground facility with which communication is established. Such information will assist FAA ATC facilities to identify and flight follow unmanned free balloons operating in the airspace.

UA.II.B.K4c  Emergency airborne inspection of other aircraft (AIM 7-6-11)

a. Providing airborne assistance to another aircraft may involve flying in very close proximity to that aircraft. Most pilots receive little, if any, formal training or instruction in this type of flying activity. Close proximity flying without sufficient time to plan (i.e., in an emergency situation), coupled with the stress involved in a perceived emergency can be hazardous.

b. The pilot in the best position to assess the situation should take the responsibility of coordinating the airborne intercept and inspection, and take into account the unique flight characteristics and differences of the category(s) of aircraft involved.

c. Some of the safety considerations are:

1. 1. Area, direction and speed of the intercept;
   2. Aerodynamic effects (i.e., rotorcraft downwash);
   3. Minimum safe separation distances;
   4. Communications requirements, lost communications procedures, coordination with ATC;
   5. Suitability of diverting the distressed aircraft to the nearest safe airport; and
   6. Emergency actions to terminate the intercept.

d. Close proximity, inflight inspection of another aircraft is uniquely hazardous. The pilot-in-command of the aircraft experiencing the problem/emergency must not relinquish control of the situation and/or jeopardize the safety of their aircraft. The maneuver must be accomplished with minimum risk to both aircraft.

UA.II.B.K4d  Precipitation static (AIM 7-6-12)

a. Precipitation static is caused by aircraft in flight coming in contact with uncharged particles. These particles can be rain, snow, fog, sleet, hail, volcanic ash, dust; any solid or liquid particles. When the aircraft strikes these neutral particles the positive element of the particle is reflected away from the aircraft and the negative particle adheres to the skin of the aircraft. 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 go into “CORONA.” That is, it will discharge the static electricity from the extremities of the aircraft, such as the wing tips, horizontal stabilizer, vertical stabilizer, antenna, propeller tips, etc. This discharge of static electricity is what you will hear in your headphones and is what we call P-static.

b. A review of pilot reports often shows different symptoms with each problem that is encountered. The following list of problems is a summary of many pilot reports from many different aircraft. Each problem was caused by P-static:

1. 1. Complete loss of VHF communications.
   2. Erroneous magnetic compass readings (30 percent in error).
   3. High pitched squeal on audio.
   4. Motor boat sound on audio.
   5. Loss of all avionics in clouds.
   6. VLF navigation system inoperative most of the time.
   7. Erratic instrument readouts.
   8. Weak transmissions and poor receptivity of radios.
   9. “St. Elmo’s Fire” on windshield.

c. Each of these symptoms is caused by one general problem on the airframe. This problem is the inability of the accumulated charge to flow easily to the wing tips and tail of the airframe, and properly discharge to the airstream.

d. Static dischargers work on the principal of creating a relatively easy path for discharging negative charges that develop on the aircraft by using a discharger with fine metal points, carbon coated rods, or carbon wicks rather than wait until a large charge is developed and discharged off the trailing edges of the aircraft that will interfere with avionics equipment. This process offers approximately 50 decibels (dB) static noise reduction which is adequate in most cases to be below the threshold of noise that would cause interference in avionics equipment.

e. It is important to remember that precipitation static problems can only be corrected with the proper number of quality static dischargers, properly installed on a properly bonded aircraft. P-static is indeed a problem in the all weather operation of the aircraft, but there are effective ways to combat it. All possible methods of reducing the effects of P-static should be considered so as to provide the best possible performance in the flight environment.

f. A wide variety of discharger designs is available on the commercial market. The inclusion of well-designed dischargers may be expected to improve airframe noise in P-static conditions by as much as 50 dB. Essentially, the discharger provides a path by which accumulated charge may leave the airframe quietly. This is generally accomplished by providing a group of tiny corona points to permit onset of corona-current flow at a low aircraft potential. Additionally, aerodynamic design of dischargers to permit corona to occur at the lowest possible atmospheric pressure also lowers the corona threshold. In addition to permitting a low-potential discharge, the discharger will minimize the radiation of radio frequency (RF) energy which accompanies the corona discharge, in order to minimize effects of RF components at communications and navigation frequencies on avionics performance. These effects are reduced through resistive attachment of the corona point(s) to the airframe, preserving direct current connection but attenuating the higher-frequency components of the discharge.

g. Each manufacturer of static dischargers offers information concerning appropriate discharger location on specific airframes. Such locations emphasize the trailing outboard surfaces of wings and horizontal tail surfaces, plus the tip of the vertical stabilizer, where charge tends to accumulate on the airframe. Sufficient dischargers must be provided to allow for current-carrying capacity which will maintain airframe potential below the corona threshold of the trailing edges.

h. In order to achieve full performance of avionic equipment, the static discharge system will require periodic maintenance. A pilot knowledgeable of P-static causes and effects is an important element in assuring optimum performance by early recognition of these types of problems.

UA.II.B.K4e  Light amplification by stimulated emission of radiation (laser) operations and reporting illumination of aircraft (AIM 7-6-13)

a. Lasers have many applications. Of concern to users of the National Airspace System 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. However, some laser systems produce light which is invisible to the human eye.

b. FAA regulations prohibit the disruption of aviation activity by any person on the ground or in the air. The FAA and the Food and Drug Administration (the Federal agency that has the responsibility to enforce compliance with Federal requirements for laser systems and laser light show products) are working together to ensure that operators of these devices do not pose a hazard to aircraft operators.

c. 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 produce permanent eye damage. Pilots should make themselves aware of where these activities are being conducted and avoid these areas if possible.

d. Recent and increasing incidents of unauthorized illumination of aircraft by lasers, as well as the proliferation and increasing sophistication of laser devices available to the general public, dictates that the FAA, in coordination with other government agencies, take action to safeguard flights from these unauthorized illuminations.

e. Pilots should report laser illumination activity to the controlling Air Traffic Control facilities, Federal Contract Towers or Flight Service Stations as soon as possible after the event. The following information should be included:

1. 1. UTC Date and Time of Event.
   2. Call Sign or Aircraft Registration Number.
   3. Type Aircraft.
   4. Nearest Major City.
   5. Altitude.
   6. Location of Event (Latitude/Longitude and/or Fixed Radial Distance (FRD)).
   7. Brief Description of the Event and any other Pertinent Information.

f. Pilots are also encouraged to complete the Laser Beam Exposure Questionnaire located on the FAA Laser Safety Initiative website at http://www.faa.gov/about/initiatives/lasers/ and submit electronically per the directions on the questionnaire, as soon as possible after landing.

g. When a laser event is reported to an air traffic facility, a general caution warning will be broadcasted on all appropriate frequencies every five minutes for 20 minutes and broadcasted on the ATIS for one hour following the report.

h. When these activities become known to the FAA, Notices to Air Missions (NOTAMs) are issued to inform the aviation community of the events. Pilots should consult NOTAMs or the Chart Supplement for information regarding these activities.

UA.II.B.K4f  Avoiding flight in the vicinity of thermal plumes such as smoke stacks and cooling towers (AIM)

17.1 Flight Hazards Exist Around Exhaust Plumes.

Exhaust plumes are defined as visible or invisible emissions from power plants, industrial production facilities, or other industrial systems that release large amounts of vertically directed unstable gases (effluent). High temperature exhaust plumes can 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 hazards are most critical during low altitude flight in calm and cold air, especially in and around approach and departure corridors or airport traffic areas.

Whether plumes are visible or invisible, the total extent of their turbulent affect is difficult to predict. Some studies do predict that the significant turbulent effects of an exhaust plume can extend to heights of over 1,000 feet above the height of the top of the stack or cooling tower. Any effects will be more pronounced in calm stable air where the plume is very hot and the surrounding area is still and cold. Fortunately, studies also predict that any amount of crosswind will help to dissipate the effects. However, the size of the tower or stack is not a good indicator of the predicted effect the plume may produce. The major effects are related to the heat or size of the plume effluent, the ambient air temperature, and the wind speed affecting the plume. Smaller aircraft can expect to feel an effect at a higher altitude than heavier aircraft.

UA.II.B.K4g  Flying in the wire environment (FAA-G-8082-22 Ch. 11)

Antenna Towers Extreme caution should be exercised when flying less than 2,000 feet AGL because of numerous skeletal structures, such as radio and television antenna towers, that exceed 1,000 feet AGL with some extending higher than 2,000 feet AGL. 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.

Additionally, new towers may not be on your current chart because the information was not received prior to the printing of the chart.

UA.II.B.K5  The NOTAM system, including how to obtain an established NOTAM through Flight Service (FAA-H-8083-25 Ch. 1)

Notices to Airmen (NOTAM)

Notices to Airmen, or NOTAMs, are time-critical aeronautical information either temporary in nature or not sufficiently known in advance to permit publication on aeronautical charts or in other operational publications. The information receives immediate dissemination via the National Notice to Airmen (NOTAM) System. NOTAMs contain current notices to airmen that are considered essential to the safety of flight, as well as supplemental data affecting other operational publications. There are many different reasons that NOTAMs are issued. Following are some of those reasons:

• Hazards, such as air shows, parachute jumps, kite flying, and rocket launches

• Flights by important people such as heads of state

• Closed runways

• Inoperable radio navigational aids

• Military exercises with resulting airspace restrictions

Inoperable lights on tall obstructions • Temporary erection of obstacles near airfields

• Passage of flocks of birds through airspace (a NOTAM in this category is known as a BIRDTAM)

• Notifications of runway/taxiway/apron status with respect to snow, ice, and standing water (a SNOWTAM)

• Notification of an operationally significant change in volcanic ash or other dust contamination (an ASHTAM)

• Software code risk announcements with associated patches to reduce specific vulnerabilities

NOTAM information is generally classified into four categories: NOTAM (D) or NOTAMs that receive distant dissemination, distant and Flight Data Center (FDC) NOTAMs, Pointer NOTAMs, and Military NOTAMs pertaining to military airports or NAVAIDs that are part of the NAS. NOTAMs are available through Flight Service Station (FSS), Direct User Access Terminal Service (DUATS), private vendors, and many online websites.

NOTAM (D) Information

NOTAM (D) information is disseminated for all navigational facilities that are part of the NAS, and all public use airports, seaplane bases, and heliports listed in the Chart Supplement U.S. (formerly Airport/Facility Directory). NOTAM (D) information now includes such data as taxiway closures, personnel and equipment near or crossing runways, and airport lighting aids that do not affect instrument approach criteria, such as visual approach slope indicator (VASI). All D NOTAMs are required to have one of the following keywords as the first part of the text: RWY, TWY, RAMP, APRON, AD, OBST, NAV, COM, SVC, AIRSPACE, (U), or (O). [Figure 1-19]

FDC NOTAMs

FDC NOTAMs are issued by the National Flight Data Center and contain information that is regulatory in nature pertaining to flight including, but not limited to, changes to charts, procedures, and airspace usage. FDC NOTAMs refer to information that is regulatory in nature and includes the following:

• Interim IFR flight procedures:

1. Airway structure changes

2. Instrument approach procedure changes (excludes Departure Procedures (DPs) and Standard Terminal Arrivals (STARs)

3. Airspace changes in general

4. Special instrument approach procedure changes

• Temporary flight restrictions (discussed in Chapter 15):

1. Disaster areas

2. Special events generating a high degree of interest

3. Hijacking

NOTAM Dissemination and Availability

The system for disseminating aeronautical information is made up of two subsystems: the Airmen’s Information System (AIS) and the NOTAM System. The AIS consists of charts and publications and is disseminated by the following methods:

Aeronautical charts depicting permanent baseline data:

• IFR Charts—Enroute High Altitude Conterminous U.S., Enroute Low Altitude Conterminous U.S., Alaska Charts, and Pacific Charts

• U.S. Terminal Procedures—Departure Procedures (DPs), Standard Terminal Arrivals (STARs) and Standard Instrument Approach Procedures (SIAPs)

• VFR Charts—Sectional Aeronautical Charts, Terminal Area Charts (TAC), and World Aeronautical Charts (WAC)

Flight information publications outlining baseline data:

• Notices to Airmen (NTAP)—Published by System Operations Services, System Operations and Safety, Publications, every 28 days)

• Chart Supplement U.S. (formerly Airport/Facility Directory)

• Pacific Chart Supplement

• Alaska Supplement

• Alaska Terminal

• Aeronautical Information Manual (AIM)

NOTAMs are available in printed form through subscription from the Superintendent of Documents, from an FSS, or online at PilotWeb (www.pilotweb.nas.faa.gov), which provides access to current NOTAM information. Local airport NOTAMs can be obtained online from various websites. Some examples are www.fltplan.com and www. aopa.org/whatsnew/notams.html. Most sites require a free registration and acceptance of terms but offer pilots updated NOTAMs and TFRs.

UA.II.B.K6  Operator equipment for night flight (AC 107-2A 5.7)

5.7 Civil Twilight and Operations at Night. Night is defined in § 1.1 as the time between the end of evening civil twilight and the beginning of morning civil twilight, as published in The Air Almanac, converted to local time. In the continental United States, evening civil twilight is the period of sunset until 30 minutes after sunset and morning civil twilight is the period of 30 minutes prior to sunrise until sunrise. In Alaska, the definition of civil twilight differs and is described in The Air Almanac. The Air Almanac provides tables to determine sunrise and sunset at various latitudes. These tables can also be downloaded from the Naval Observatory and customized for a particular location. The link for the Naval Observatory is https://www.usno.navy.mil/search?SearchableText=air+ almanac+.

5.7.1 Civil Twilight Operations. When small UAS operations occur during civil twilight, the small unmanned aircraft must be equipped with anti-collision lighting visible for at least 3 statute miles (sm). However, the remote PIC may reduce the visible distance of the lighting to less than 3 sm during flight if he or she has determined that it would be in the interest of safety to do so. For more information on this determination, see paragraph 5.7.2.2.

5.7.2 Operations at Night. Small UAS operations at night may occur only under the two risk mitigation measures listed in § 107.29. First, the remote PIC must have completed either an initial knowledge test or recurrent training that have been updated to include night operations. Second, the small unmanned aircraft must have lighted anti-collision lighting that is visible for at least 3 sm. The remote pilot may rely upon manufacturer statements indicating the anti-collision lighting is visible for 3 sm. However, the remote pilot ultimately remains responsible for verifying that anti-collision lighting is operational, visible for 3 sm, and has a flash rate sufficient to avoid a collision at the operating location.

5.7.2.1 A certificated remote pilot receives night operations privileges and may operate at night only after completing either a knowledge test that contains questions on night physiology and night visual illusions, or through completion of recurrent training. The recurrent training contains the topics of night physiology and night visual illusions. Chapter 6 provides a detailed explanation of both paths for night operations privileges.

5.7.2.2 AC 107-2A As is the case for civil twilight operations, the small unmanned aircraft must be equipped with anti-collision lighting that is visible for at least 3 sm. However, the remote PIC may reduce the intensity of the light if the remote PIC determines it is in the interest of safety to do so. For example, a bright light or a bright strobe light on the small unmanned aircraft in very close proximity to the remote pilot could cause the remote pilot to lose the ability to observe the small unmanned aircraft’s location, speed, attitude, or altitude with accuracy. The remote pilot maintains the discretion to reduce the intensity of the anti-collision lighting when he or she determines it would be in the best interest of safety to do so. Discretion is an important component of § 107.19, which states that the remote PIC is directly responsible for the operation of the small unmanned aircraft. The remote PIC must ensure the operation of the small unmanned aircraft complies with all regulations of part 107. This includes the requirement to maintain the capability of visually observing the small unmanned aircraft. Section 107.29 does not require small unmanned aircraft operating during the day to have illuminated small unmanned aircraft anti-collision lighting. Lighting is generally not effective for mitigating risk of collision during daytime operations. Remote pilots may exercise their discretion, however, and elect to have lighting on during all daytime operations.

5.7.2.3 A remote PIC or operator may request a waiver of the anti-collision lighting requirement for operations at night and during civil twilight. The process for requesting a waiver is two-fold: the requester must (1) fully describe the proposed operation, and (2) establish the operation can be safely conducted under the terms of a Certificate of Waiver (CoW). Paragraph 5.20 below describes the application process for waivers.

UA.II.B.K7  Ground structures and ground structure lighting (AC 70/7460-1M)

2.1 Structures to be Marked and Lighted

Any temporary or permanent structure, including all appurtenances, that exceeds any obstruction standard contained in 14 CFR Part 77 or an overall height of 200 feet (60.96m) above ground level (AGL) should be marked and/or lighted. However, an FAA aeronautical study may reveal that the absence of marking and/or lighting will not impair aviation safety. Conversely, the object may present such an extraordinary hazard potential that higher standards may be recommended for increased conspicuity to ensure aviation safety. Recommendations for marking and/or lighting structures can vary, depending on terrain features, weather patterns, geographic location, number of structures, and overall design layout. The FAA may also recommend marking and/or lighting a structure that does not exceed 200 feet (60.96 m) AGL or 14 CFR Part 77 standards because of its particular location. The marking and lighting configurations are illustrated in Appendix A.

2.2 Guyed Structures

The guys of a 2,000-foot (609.60 m) skeletal tower are anchored between 1,600 feet (487.68 m) and 2,000 feet (609.60 m) from the base of the structure. This places a portion of the guys 1,500 feet (457.20 m) from the tower at a height of between 125 feet (38.10 m) and 500 feet (152.40 m) AGL. Title 14 CFR Part 91, Section 119, requires pilots, when operating over other than congested areas, to remain at least 500 feet (152.40 m) from man-made structures. Therefore, the tower must be cleared by 2,000 feet (609.60 m) horizontally to avoid all guy wires. Properly maintained marking and lighting are important for increased conspicuity because the guys of a structure are difficult to see until the aircraft is dangerously close.

2.3 Marking and Lighting Equipment

Considerable effort and research was expended to determine the minimum marking and lighting systems and quality of materials that will produce an acceptable level of aviation safety. The FAA will recommend only those marking and lighting systems that meet established technical standards and commercial outside lighting should not be used in lieu of FAA recommended marking and/or lighting. While additional lights may be desirable to identify an obstruction to air navigation, and may on occasion be recommended, the FAA will recommend minimum standards in the interest of safety, economy, and related concerns. Therefore, to provide an adequate level of safety, obstruction lighting systems should be installed, operated, and maintained in accordance with the recommended standards herein. Chapter 15 contains descriptions of FAA- approved obstruction marking and lighting equipment and information referred to in this AC.

UA.II.B.K8  Hazards on the ground that do not have lighting (AIM 7-6-4)

7-6-4 Obstructions To Flight

a. General. Many structures exist that could significantly affect the safety of your flight when operating below 500 feet above ground level (AGL), and particularly below 200 feet AGL. While 14 CFR Part 91.119 allows flight below 500 feet AGL when over sparsely populated areas or open water, such operations involve increased safety risks. At and below 200 feet AGL there are numerous power lines, antenna towers, etc., that are not marked and lighted and/or charted as obstructions and, therefore, may not be seen in time to avoid a collision. Notices to Air Missions NOTAMs are issued on those lighted structures experiencing temporary light outages. However, some time may pass before the FAA is notified of these outages, and the NOTAMs issued, thus pilot vigilance is imperative. Additionally, new obstructions may not be on current charts because the information was not received prior to the FAA publishing the chart.

b. Antenna Towers. Extreme caution should be exercised when flying less than 2,000 feet AGL because of numerous skeletal structures, such as radio and television antenna towers, that exceed 1,000 feet AGL with some extending higher than 2,000 feet AGL. 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.

c. Overhead Wires. Overhead transmission and utility lines often span approaches to runways, natural flyways such as lakes, rivers, gorges, and canyons, and cross other landmarks pilots frequently follow such as highways, railroad tracks, etc. As with antenna towers, these power transmission and/or utility lines and the supporting structures of these lines may not always be readily visible. The wires may be virtually impossible to see under certain conditions. Spherical markers may be used to identify overhead wires and catenary transmission lines and may be lighted. In some locations, the supporting structures of overhead transmission lines are equipped with unique sequence flashing white strobe light systems to indicate that there are wires between the structures. The flash sequence for the wire support structures will be middle, top, and bottom with all lights on the same level flashing simultaneously. However, not all power transmission and/or utility lines require notice to the FAA as they do not exceed 200 feet AGL or meet the obstruction standard of 14 CFR Part 77 and, therefore, are not marked and/or lighted. All pilots are cautioned to remain extremely vigilant for power transmission and/or utility lines and their supporting structures when following natural flyways or during the approach and landing phase. This is particularly important for seaplane and/or float equipped aircraft when landing on, or departing from, unfamiliar lakes or rivers.

d. Wind Turbines. The number, size, and height of individual wind turbines and wind turbine farms have increased over time. The locations of wind turbine farms have also expanded to areas more commonly flown by VFR pilots and to all regions of the United States. VFR pilots should be aware that many wind turbines are exceeding 499 feet AGL in height, which may affect minimum safe VFR altitudes in uncontrolled airspace. In addition, many wind turbines are encroaching on the 700 foot AGL floor of controlled airspace (Class E). Pilots are cautioned to maintain appropriate safe distance (laterally, vertically, or both). Wind turbines are typically charted on Visual Flight Rules (VFR) Sectional Charts and/or Terminal Area Charts. For a description of how wind turbines and wind turbine farms are charted, refer to the FAA Aeronautical Chart User’s Guide. Wind turbines are normally painted white or light gray to improve daytime conspicuity. They are typically lit with medium-intensity, flashing red lights, placed as high as possible on the turbine nacelle (not the blade tips), that should be synchronized to flash together; however, not all wind turbine units within a farm need to be lighted, depending on their location and height. Sometimes, only the perimeter of the wind turbine farm and an arrangement of interior wind turbines are lit. Some wind turbine farms use Aircraft Detection Lighting Systems (ADLS), which are proximity sensor-based systems designed to detect aircraft as they approach the obstruction. This system automatically activates the appropriate obstruction lights until they are no longer needed based on the position of the transiting aircraft. This technology reduces the impact of nighttime lighting on nearby communities and migratory birds and extends the life expectancy of the obstruction lights. For more information on how obstructions such as wind turbines are marked and lighted, refer to Advisory Circular 70/7460-1, Obstruction Marking and Lighting. Pilots should be aware that wind turbines in motion could result in limitations of air traffic services in the vicinity of the wind turbine farms.

e. Meteorological (MET) Evaluation Towers. MET towers are used by wind energy companies to determine feasible sites for wind turbines. Some of these towers are less than 200 feet AGL. These structures are portable, erected in a matter of hours, installed with guyed wires, and constructed from a galvanized material often making them difficult to see in certain atmospheric conditions. Markings for these towers include alternating bands of aviation orange and white paint, and high-visibility sleeves installed on the outer guy wires. However, not all MET towers follow these guidelines, and pilots should be vigilant when flying at low altitude in remote or rural areas.

f. Other Objects/Structures. There are other objects or structures that could adversely affect your flight such as temporary construction cranes near an airport, newly constructed buildings, new towers, etc. Many of these structures do not meet charting requirements or may not yet be charted because of the charting cycle. Some structures do not require obstruction marking and/or lighting, and some may not be marked and lighted even though the FAA recommended it. VFR pilots should carefully review NOTAMS for temporary or permanent obstructions along the planned route of flight during their preflight preparations. Particular emphasis should be given to obstructions in the vicinity of the approach and departure ends of the runway complex or any other areas where flight below 500 feet AGL is planned or likely to occur.

UA.II.B.K9  Manned aircraft lighting (CFR-2010 Ch. 13)

Aircraft Lighting

In order to see other aircraft more clearly, regulations require that all aircraft operating during the night hours have special lights and equipment. The requirements for operating at night are found in Title 14 of the Code of Federal Regulations (14 CFR) part 91. In addition to aircraft lighting, the regulations also provide a definition of night flight in accordance with 14 CFR part 91, currency requirements, fuel reserves, and necessary electrical systems.

Position lights enable a pilot to locate another aircraft, as well as help determine its direction of flight. The approved aircraft lights for night operations are a green light on the right cabin side or wingtip, a red light on the left cabin side or wingtip, and a white position light on the tail. In addition, f lashing aviation red or white anticollision lights are required for night flights. These flashing lights can be in a number of locations, but are most commonly found on the top and bottom of the cabin.

Figure 13-7 shows examples of aircraft lighting. By interpreting the position lights on other aircraft, the pilot in aircraft 3 can determine whether the aircraft is flying in the opposite direction or is on a collision course. If a red position light is seen to the right of a green light, such as shown by aircraft 1, it is flying toward aircraft 3. A pilot should watch this aircraft closely and be ready to change course. Aircraft 2, on the other hand, is flying away from aircraft 3, as indicated by the white position light.

UA.II.B.K10  sUAS lighting requirements (AC 107-2A)

5.7.1 Civil Twilight Operations.

When small UAS operations occur during civil twilight, the small unmanned aircraft must be equipped with anti-collision lighting visible for at least 3 statute miles (sm). However, the remote PIC may reduce the visible distance of the lighting to less than 3 sm during flight if he or she has determined that it would be in the interest of safety to do so. For more information on this determination, see paragraph 5.7.2.2.

5.7.2 Operations at Night.

Small UAS operations at night may occur only under the two risk mitigation measures listed in § 107.29. First, the remote PIC must have completed either an initial knowledge test or recurrent training that have been updated to include night operations. Second, the small unmanned aircraft must have lighted anti-collision lighting that is visible for at least 3 sm. The remote pilot may rely upon manufacturer statements indicating the anti-collision lighting is visible for 3 sm. However, the remote pilot ultimately remains responsible for verifying that anti-collision lighting is operational, visible for 3 sm, and has a flash rate sufficient to avoid a collision at the operating location.

5.7.2.2  As is the case for civil twilight operations, the small unmanned aircraft must be equipped with anti-collision lighting that is visible for at least 3 sm. However, the remote PIC may reduce the intensity of the light if the remote PIC determines it is in the interest of safety to do so. For example, a bright light or a bright strobe light on the small unmanned aircraft in very close proximity to the remote pilot could cause the remote pilot to lose the ability to observe the small unmanned aircraft’s location, speed, attitude, or altitude with accuracy. The remote pilot maintains the discretion to reduce the intensity of the anti-collision lighting when he or she determines it would be in the best interest of safety to do so. Discretion is an important component of § 107.19, which states that the remote PIC is directly responsible for the operation of the small unmanned aircraft. The remote PIC must ensure the operation of the small unmanned aircraft complies with all regulations of part 107. This includes the requirement to maintain the capability of visually observing the small unmanned aircraft. Section 107.29 does not require small unmanned aircraft operating during the day to have illuminated small unmanned aircraft anti-collision lighting. Lighting is generally not effective for mitigating risk of collision during daytime operations. Remote pilots may exercise their discretion, however, and elect to have lighting on during all daytime operations.