4-1 CHAPTER 4. COMMUNICATIONS, NAVIGATION, AND SURVEILLANCE
SYSTEMS GUIDANCE FOR OPERATIONS IN OCEANIC AND REMOTE
CONTINENTAL AIRSPACE
4.1 Communications, Navigation, and Surveillance Improvements—Impact on ATS.
4.1.1 Technological Advances. Technological advances in communications, navigation, and surveillance systems all contribute to an air traffic system that provides increased navigational accuracy and allows you and your aircraft to interact more quickly with controllers. These advances have also improved controller-pilot communications, navigation accuracy, and aircraft surveillance reporting. This enhanced communications, navigation, and surveillance capability greatly reduces the errors and retransmissions that hampered oceanic flights just a few years ago. These safety improvements have facilitated corresponding improvements in efficiency and capacity by reducing separation minima, allowing controllers to space aircraft closer together. Trials of new separation minima or implementations of new operating procedures are common in oceanic airspace. Operators should therefore make sure they have the most up-to-date information concerning the airspace in which they will be flying. U.S. and foreign State AIPs, NOTAMs, and related publications are normally the best sources of current information.
International operations manuals that consolidate this information should be current.
4.1.2 ADS-B. ADS-B supports these improvements by providing a higher update and enhanced accuracy of surveillance information over the current radar-based surveillance systems.
4.1.3 S pace- Based ADS-B. In 2019, a constellation of low-Earth orbit satellites with ADS-B receivers began supplying surveillance data to air traffic service providers (ATSP).
Shortly thereafter, ICAO published a new separation standard for areas under ADS-B surveillance where VHF voice communications are not available. This new separation standard allows aircraft to be more closely spaced in oceanic areas, which in turn allows more efficient routing. While space-based ADS-B update rates are comparable to those of some domestic radar systems, communication systems traditionally used in oceanic and remote continental airspace do not perform as quickly as the VHF voice communications used in domestic environments. Consequently, aircraft cannot yet be spaced as closely as in domestic areas. As communication systems evolve, allowable separation between aircraft will likely be reduced further.
4.2 Performance-based Operations.
4.2.1 Measures of Performance. Performance-based operations rely on RCP, RNP, and RSP. It uses these three primary measures of performance to determine required separation between flights, both in radar contact and in oceanic and remote continental airspace.
ATS providers determine separation requirements based on a combination of these three performance indicators.
4.2.2 RCP. R CP establishes aircraft/controller communications timeline, equipment, and flightcrew training standards. Generally, you can measure RCP in terms of the timeline required to complete the communication transaction and the continuity, availability, and
4-2 integrity of the transaction. In oceanic and remote continental airspace, RCP 240 and RCP 400 are the prevalent performance standards.
4.2.2.1 RCP 240 requires a 99.9 percent probability (continuity) the communications transaction will complete in less than 240 seconds (timeline). It also requires a
99.99 percent probability the communication can be initiated (availability) and no more than 10-5 communications transaction malfunctions per flight-hour (integrity).
4.2.2.2 RCP 400 requires a 99.9 percent probability (continuity) the communications transaction will complete in less than 400 seconds (timeline). It also requires a
99.9 percent probability the communication can be initiated (availability) and no more than 10-5 communications transaction malfunctions per flight-hour (integrity).
4.2.2.3 U.S. operators desiring Performance-based Communications and Surveillance (PBCS) approval for qualifying systems (e.g., with RCP 240 and RSP 180) can obtain OpSpec/MSpec/LOA A056, Data Link Communications. See paragraph 4.5 below.
4.2.2.4 For additional details, please refer to AC 90-117, Data Link Communications;
and the ICAO Doc 10037, Global Operational Data Link (GOLD) Manual, Appendix B, RCP Specifications, and ICAO Doc 9869, Performance-based Communication and Surveillance (PBCS) Manual, at https://store.icao.int.
4.2.3 RNP. RNP establishes aircraft navigation accuracy, equipment, and flightcrew training standards. ICAO Doc 9613, Performance-based Navigation (PBN) Manual, outlines these standards. Generally, we measure these standards in terms of accuracy, integrity, continuity, availability, and functionality. Oceanic and remote continental airspace ATS providers primarily provide RNP 10 (also known as RNAV 10) and RNP 4-based separation minima. RNP 2 applications have also become available for oceanic and remote continental airspace, to be used by individual States as necessary to meet their airspace requirements. In all cases, ATS providers will apply appropriate separation minima between adjacent aircraft based on the capabilities each aircraft operator files in the flight plan. You must only indicate the oceanic RNP capability authorized in your OpSpec/MSpec/LOA B036, Oceanic and Remote Continental Navigation using Multiple Long-Range Navigation Systems.7
1. RNP 10 requires accuracy to be within 10 NM 95 percent of the time.
2. RNP 4 requires accuracy to be within 4 NM 95 percent of the time and within 8 NM
99.999 percent of the time.
3. RNP 2 requires accuracy to be within 2 NM 95 percent of the time and within 4 NM
99.999 percent of the time.
7 Regulatory reference is § 91.169, which refers to § 91.153. This requires the flight plan to include “any other information the pilot in command (PIC) or ATC believes is necessary for ATC purposes.”
4-3 Note: Regardless of RNP value, pilots are expected to fly the centerline (or up to 2 NM right of course, where use of SLOP is authorized).
4.2.4 RS P . RSP establishes aircraft/controller surveillance timeline and equipment standards.
Generally, you can measure RSP in terms of the timeline required to complete the transaction and the continuity, availability, and integrity of the transaction. In oceanic and remote continental airspace, RSP 180 and RSP 400 are the prevalent performance standards.
4.2.4.1 R SP 180 requires a 99 percent probability (continuity) the surveillance transaction will complete in less than 180 seconds (timeline). It also requires a
99.99 percent probability the communication can be initiated (availability) and no more than 10-5 communications transaction malfunctions per flight-hour (integrity).
4.2.4.2 RSP 400 requires a 99 percent probability (continuity) the surveillance transaction will complete in less than 400 seconds (timeline). It also requires a
99.9 percent probability the communication can be initiated (availability) and no more than 10-5 communications transaction malfunctions per flight-hour (integrity).
4.2.4.3 For additional details, please see ICAO Doc 10037, Appendix C, RSP Specifications.
4.2.5 A ccess to Performance -based Separation. Communications, navigation, and surveillance capabilities of aircraft and crew determine eligibility for authorizations (i.e., via OpSpecs, MSpecs, and LOAs), which in turn allow operators to take advantage of performance-based separation in oceanic and remote continental airspace. The significant improvements in communications, navigation, and surveillance systems have allowed air traffic controllers to reduce separation between aircraft, expanding access to more favorable routing and/or altitudes that offer savings in time and fuel.
Note: F or a list of pertinent OpSpecs/MSpecs/LOAs, please see Appendix B , Special Areas of Operation and OpSpecs/MSpecs/LOAs.
4.3 V oice Communications in Oceanic Airspace. When operating over the high seas, ICAO Annex 2 requires you to m aintain a continuous air-to-ground voice communication watch with the appropriate ATS authority on the appropriate communication channel.
Note: It is not acceptable to depend solely on other aircraft providing a radio relay to satisfy this requirement. The appropriate authority for the airspace where you conduct the flight may prescribe the aeronautical stations and frequencies used for two-way communications.
4.3.1 H F Radio Communications. HF radios have been in use for almost a century over oceanic and remote continental areas. As technological advances lead to more sophisticated methods of communication, HF equipment has also improved. HF radios now offer digital tuning, compact size, selective calling systems (SELCAL) (see paragraph 4.3.2
4-4 below), and new antenna concepts. Consider the following when using HF communications:
4.3.1.1 HF radio calls are typically made to a radio operator, who in turn electronically relays the information, via keyboard and pre-formatted messages, to air traffic controllers in oceanic centers. There is some delay between your requests and ATC clearances, where the radio operator coordinates with the appropriate controller. Radio operators do not have the authority to issue ATC clearances on their own.
4.3.1.2 Communications over HF radio rely heavily on proper radio terminology and scripted reports. Use the published guidance found in en route publications or the Aeronautical Information Manual (AIM) to make sure you deliver messages in the proper format. Speak at a moderate speed using the internationally accepted phraseology. You may find ICAO standard phraseology in ICAO Doc 9432, Manual of Radiotelephony. This document and other ICAO reference materials are available on ICAO’s website at https://store.icao.int.
4.3.1.3 If ATC uses the terms “expect” or “when can you accept,” they have not granted you a clearance. Typically, oceanic radio operators will use the phraseology “ATC clears…” when relaying a clearance.
4.3.1.4 ICAO Doc 4444, Procedures for Air Navigation Services—Air Traffic Management, requires the flightcrew to read back level instructions, heading and speed instructions, and ATC route clearances. Ensure that the radio operator acknowledges your exact read back to confirm that you correctly heard the instructions.
4.3.1.5 In general, higher frequencies (above 10.0 megahertz (MHz)) work better during daylight and lower frequencies (below 10.0 MHz) at night. It is common to use several frequencies on one flight while communicating with the same ATS provider.
4.3.1.6 HF communications are dependent on transmitted signals striking the ionosphere and reflecting back to antennae at ground stations. The ionosphere is susceptible to interference from space weather, resulting in periods where HF reception is marginal or unreadable. You may especially notice this phenomenon in polar regions above 60° N or below 60° S and during periods of significant solar activity.
4.3.2 SELCAL. SELCAL is a means to alert an individual aircraft that a ground station wishes to communicate with it. ATS providers can transmit SELCAL signals over VHF or HF.
The signals produce an audio tone and possibly a cockpit indication that alerts you to initiate contact with the appropriate ATC unit.
4.3.2.1 The SELCAL codes are controlled by a commercial service and are assigned to a specific aircraft. Since the number of unique SELCAL codes is less than
4-5 the number of aircraft with SELCAL capability, multiple aircraft could be operating and logged in with the same SELCAL code assignment.
4.3.2.2 When you apply for SELCAL codes for your aircraft, the issuing company will de-conflict duplicate codes by region as much as possible. However, aircraft flying in multiple regions may encounter another aircraft using the same code. Therefore, you should be certain that the ATS radio operator uses your exact call sign when responding to a SELCAL.
4.3.2.3 New SELCAL systems use 32 tones, instead of only 16 tones currently used, and thereby increase the number of unique identifiers exponentially. The ICAO Communication Panel approved the global implementation of SELCAL 32 for revisions to take effect in November 2022. SELCAL 32 compliant equipment became available beginning in 2020. Operators with 16-tone HF SELCAL systems may continue to encounter a duplicate code situation.
4.3.2.4 Check HF SELCAL even when your CPDLC is working properly. You should do a SELCAL check prior to oceanic entry and then again at each control area (CTA) boundary. See the sample transcript of an HF SELCAL check below.
Sample Transcript of HF SELCAL Check HF call from the air: “New York Radio, Airline 123, request SELCAL Check.”
Answer from the ground:
“Airline 123, New York Radio, roger.”
[SELCAL tones transmitted] HF call from the air: [If successful] “SELCAL check good, thank you!”
4.3.3 SATVOICE. In keeping with ICAO’s recognition of SATVOICE as a valid LRCS, the FAA accommodates SATVOICE through arrangements with the recognized Aeronautical Mobile Satellite (Route) Service providers. The FAA currently restricts direct SATVOICE contact between the pilot and FAA ATC to “distress and urgency situations,” or other exceptional circumstances only. For oceanic communications with ATC via New York Radio and San Francisco Radio, relevant SATVOICE policy and short codes are published in the U.S. AIP.
4.3.3.1 The FAA requires SATVOICE equipment supporting ATS communications to be installed in accordance with AC 20-150B (or subsequent edition), Airworthiness Approval of Satellite Voice (SATVOICE) Equipment Supporting Air Traffic Service (ATS) Communication.8 Additional
8 Regulatory references are § 91.703 and ICAO Annex 2, paragraph 3.6.5.1. The U.S. AIP, in describing the “appropriate communication channel,” invokes AC 20-150B.
4-6 r equirements are listed in the U.S. AIP. Portable satellite phones are not approved for normal and routine ATC communications.
4.3.3.2 Addi tionally, the FAA requires a SATVOICE Callback Check when pilots use SATVOICE to communicate with ATC via New York Radio or San Francisco Radio. A sample transcript is here:
Sample Transcript of SATVOICE Callback Check SATVOICE call from the air:
“New York Radio, Airline 123, request SATVOICE Callback Check.”
For aircraft equipped with both Inmarsat and Iridium:
“… on Inmarsat/Iridium (as applicable)” Answer from the ground:
“Airline 123, roger, terminating call, will call you right back” New SATVOICE call from ground:
“Airline 123, New York Radio with your SATVOICE Callback, how do you read?”
SATVOICE answer from the air:
“Loud and clear, SATVOICE Callback Check good, good day!”
4.3.3.3 If SATVOICE is used (as authorized in the relevant AIP) as the sole voice LRCS, for purposes of maintaining a continuous air-to-ground voice communication watch with the relevant ATS authority on the appropriate communication channel, several important considerations apply:
1. Flightcrews should be thoroughly familiar with SATVOICE use, to include the aural and visual alerts for incoming calls, call answering, display and selection of call priority, use of press-to-talk switches, call setup with or without the avionics phone book, call preemption, and call termination.
2. Avionics (e.g., flight management computer (FMC)) phone books should be organized in a logical, easy-to-understand manner, and flightcrews should have the appropriate number preloaded to facilitate rapid call setup with the relevant ATS authority. Calls should be managed to ensure a line is always available for an incoming “Operational High” priority (Priority 2/Q12) call from the relevant ATS authority.
3. For purposes of compliance with 14 CFR requirements on numbers of LRCS, the FAA recognizes SATVOICE as an approved LRCS only in areas where the ground infrastructure supports SATVOICE as the “sole voice LRCS.” Such services are described in the relevant AIP. In areas
4-7 lacking this designation, at least one operable HF (voice) radio is required.9
4. A s SATVOICE technology evolves, ensure that you comply with the latest guidance. In the United States, see entry in the U.S. AIP, with new changes published in the FAA’s International Notices. For additional guidance, refer to the FAA’s AIM, ICAO’s Satellite Voice Guidance Material (SVGM), a nd/or the relevant AIP.
4.3.4 Changes to Communications Procedures. Information needed on initial contact with an agency, radio frequencies, and other aspects of oceanic communications are changed frequently. Thus, it is important that you consult the appropriate AIP, international notices, current oceanic charts, and commercial en route publications for the most current information.
• ICAO NAT Doc 007, North Atlantic Operations and Airspace Manual, describes North Atlantic (NAT) operations, to include communication and navigation procedures in NAT airspace. The NAT section of ICAO Doc 7030, Regional Supplementary Procedures, currently requires HF SELCAL checks, meaning that an HF radio is required in NAT airspace.
• Commercially published navigation charts contain details of communication p rocedures on inserted panels. Exercise some caution in using this reference, as they may be on a different update cycle than the source documents and therefore could be not completely up to date.
4.4 CPDLC and Automatic Dependent Surveillance-Co ntract (ADS-C). Data link communications systems are widely used throughout the world and are normally used in concert with ADS-C systems that further improve ATS capability. CPDLC technology improves communications between aircraft and ATS providers. CPDLC replaces most of the often-challenging HF voice communications that were the only communication link with oceanic and remote continental airspace air traffic controllers for decades. With CPDLC, you and the controller transfer ATC clearance requests and instructions digitally, reducing the likelihood of miscommunication. CPDLC compliant with RCP 240 is required to fly the most efficient routes in the NAT.
Note: In ADS-C, C = “Contract.” The controller sets up one or more electronic contracts with your aircraft to automatically provide time-triggered (periodic) and/or condition-triggered (e.g., deviation event) reports. In addition, a controller, at any time, can issue a “demand” contract for a single periodic ADS-C report.
4.4.1 Title 14 CFR Requirements for LRCS. F or purposes of compliance with 14 CFR requirements on numbers of LRCS (cited in paragraph 2.3.1 above), the FAA recognizes CPDLC that is compliant with RCP 240 as an approved LRCS. Equipage with CPDLC does not eliminate the requirement for at least one operable voice LRCS. This means that
9 Regulatory references are § 91.703 and ICAO Annex 2, paragraph 3.6.5.1. The applicable AIP describes the “appropriate communication channel.”
4-8 (as is mentioned in paragraph 4.3.3.3, item 3) unless the relevant AIP authorizes SATVOICE as a sole voice LRCS, at least one operable HF (voice) radio is required.
4.4.2 A ccess to Preferred Airspace. Since equipment like CPDLC and ADS- C improves the efficiency with which aircraft in oceanic and remote continental airspace can be controlled, such better-equipped aircraft are being better served through initiatives to reserve preferred blocks of oceanic airspace for those aircraft. Preferred altitudes and routes around the world are more readily issued to aircraft equipped with robust communications, navigation, and surveillance capabilities.
4.4.3 F AA Domestic CPDLC Use of Free Text in Route Uplinks . The FAA’s domestic flight data processing systems automatically add so-called “Free Text” messages containing the entire cleared route, to all route clearance change messages. This allows pilots to more readily see and understand the given change. However, oceanic systems do not do this.
The result is that pilots accustomed to the FAA domestic display of route clearances could be confused when seeing an oceanic route uplink. Figure 4-1, Sample CPDLC Route Uplinks, shows how a CPDLC route uplink might look if sent from a U.S.
domestic system versus an oceanic system.
Figure 4-1. Sample CPDLC Route Uplinks Sample Route Uplink With Free Text (Used by domestic FAA systems) 0527Z ATC UPLINK 1/2 STATUS OPEN
CLEARED TO SUL VIA ROUTE CLEARANCE.
REST OF ROUTE UNCHANGED.
FREE
SSEL VIA -- CONTINUED -- -=--- LOG>
ATC MESSAGE "Route clearance" is readily visible.
Sample Route Uplink Without Free Text (Used by oceanic systems) 1917z ATC UPLINK 1/2 10222 ATC UPLINK 1/1
CZQX OPEN STATUS OPEN /CLEARED TO CLEARED EVRIN VIA HOIST ROUTE CLEARANCE.
VIA ROUTE CLEARANCE TANDB SEN LOAD› ACCEPT ‹REJECT SEND>
- CONTINUED - - PRINT MATC INDEX LOGA FAIL LOG> With this FMS, to view the "route clearance, the pilot must advance to the next page, then select the "ATC CLNC" prompt.
This is not a clearance to proceed direct to HOIST.
With this FMS, to view the route clearance," the pilot must select the "LOAD" prompt.
This is not a clearance to proceed direct to EVRIN.
4.5 Data Link Systems-Operational Authorization to Use. We grant operational authorization for operators to use Future Air Navigation System (FANS) data link (used in oceanic areas and in the U.S.) by issuing OpSpec/MSpec/LOA A056, as appropriate. '° Note: OpSpec/MSpec/LOA A056 also applies to VHF datalink communications in overland areas, such as Aeronautical Telecommunications Network (ATN) Baseline 1 (B1) (formerly Link 2000+), used in European airspace.
1° AC 90-117 provides information on OpSpec/MSpec/LOA A056.
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4.5.1 Oceanic Data Link Requires Authorization. U.S. operators (including part 91) must have a data link authorization to file ATC flight plan capability codes J5 and/or J7 in oceanic airspace.11 These codes denote Inmarsat and Iridium satellite communications capability, respectively. You can find our guidance on the process and procedures for operational authorization and aircraft data link system approval in the following documents:
• AC 20-140, Guidelines for Design Approval of Aircraft Data Link Communication Systems Supporting Air Traffic Services (ATS).
• AC 90-117.
4.5.2 Data Link Requirements and Standards. You can consult ICAO Doc 10037 for additional information on data link requirements and standards.
4.6 ATC in Oceanic and Remote Continental Airspace.
4.6.1 Procedural Airspace. In oceanic and remote continental airspace, ATC typically requires position reports via voice or ADS-C, and controllers apply “procedural separation,” spacing aircraft farther apart than in domestic “ATS surveillance airspace” (where radar or ADS-B surveillance is accompanied by VHF voice communication with ATC).
Space-based ADS-B provides significant improvements in surveillance, but without ATC being able to issue a vector via VHF voice communications, required separation between aircraft is greater. In areas with space-based ADS-B surveillance that lack direct VHF voice communications with the controller, ATC still therefore provides at least some elements of procedural control.
4.6.1.1 In procedural airspace, ATC issues clearances and instructions providing separation vertically and horizontally, based on the specific aircraft equipment authorizations you indicate on your flight plan.
4.6.1.2 ATC monitors your compliance with the issued clearance. Your aircraft position reports are processed for conformance with the clearance. If your aircraft is equipped with ADS-C, it provides trigger alerting for lateral and vertical deviations.
4.6.1.3 In order to make this procedural separation work the way it is designed, you must provide timely and accurate time estimates (estimated time of arrival (ETA)) and operate with strict discipline and adherence to ATC clearances and procedures, both normal and contingency.12
4.6.1.4 Controllers manage longitudinal separation in procedural airspace by assigning speeds, either true Mach number or true airspeed. Proper separation
11 AC 90-117 cites the regulatory basis for this requirement, which is § 91.123.
12 ICAO Annex 2, paragraph 3.6.2.2d), says: “if the time estimate … changes in excess of 2 minutes from that previously notified to air traffic services, … the flight crew shall notify the appropriate air traffic services unit as soon as possible.”
4-11 of aircraft is dependent upon pilots maintaining the speed assigned with the clearance (not to be confused with the speed filed on the flight plan).
• If traffic conditions permit, the controller may permit variations. However, if a controller assigns a speed, compliance with that speed is mandatory.
• Even when a controller permits variations, ICAO Annex 2 specifies that pilots must inform ATC of speed variations of Mach 0.02 or greater from the current flight plan (current clearance).
4.6.2 ICAO Procedures for Specific Geographical Areas. You will find detailed procedures for the applicable ICAO Region in ICAO Doc 7030. When flying over the high seas (international airspace, generally greater than 12 NM from the nearest shore), part 91, § 91.703 requires compliance with Annex 2. Annex 2, in turn, refers to Doc 7030. You should consider ICAO Doc 7030 regulatory.
4.6.3 U.S. ATS. Inf ormation on provision of ATS by the United States is available in FAA Order JO 7400.11, Airspace Designations and Reporting Points. Also refer to 14 CFR part 71.
4.6.3.1 Domestic Airspace. (ICAO refers to this as “Continental” Airspace). Along the coast of the United States, domestic ATC procedures (with radar or ADS-B surveillance and VHF communications) are applied in U.S. Offshore Airspace, generally extending as far as the useful range of radar and VHF communications systems permits, approximately 150-200 NM from the coast.
Note: Domestic airspace generally includes sovereign airspace over terrain and territorial waters, as well as the “high seas” airspace beyond 12 NM from the coast with ATS surveillance and VHF communications. As discussed in paragraphs 2.3.2 and 2.3.3, part 91 subpart B applies in U.S. sovereign airspace, and ICAO Annex 2 applies in “high seas” airspace.
4.6.3.2 Ocea nic Airspace. The United States provides ATS in oceanic airspace as follows:
• Atlantic Ocean: New York, Miami, and San Juan Flight Information Regions (FIR).
• Gulf of Mexico: Miami and Houston Oceanic CTAs/FIRs. Most of the Gulf of Mexico is under ADS-B surveillance, with VHF voice communications directly with the controller (above 18,000 ft mean sea level (MSL)).
• Pacific Ocean: Oakland and Anchorage CTA/FIR.
• Arctic Ocean: Anchorage Arctic CTA/FIR.
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4.6.3.3 Remote Continental Airspace. The United States provides ATS in remote continental airspace as follows: Alaska Remote Continental Airspace:
Anchorage Air Route Traffic Control Center (ARTCC).
4.6.4 Advanced Technologies and Oceanic Procedures (ATOP). U.S. controllers use the ATOP flight data processing system in the airspace of Oakland Oceanic, New York Oceanic, and Anchorage Oceanic and Arctic FIRs.
4.6.4.1 Within this airspace, ATOP allows for establishing the separation minima for all pairs of aircraft along a cleared profile, and provides aircraft profile conformance monitoring and protection.
4.6.4.2 ATOP deciphers ATC flight plan information to determine what separation standards may be applied to a particular aircraft based on filed aircraft equipage. Accordingly, you must notify ATC immediately if your communications, navigation, and surveillance equipment capability degrades below that which you listed in your flight plan.13
4.6.4.3 ATOP analyzes cleared routes of aircraft and alerts controllers of potential future conflicts (scalable to more than 2 hours ahead) with other aircraft.
ATOP also considers different separation standards applied by adjacent ATC facilities and can warn the controller when a conflict will occur based on the adjacent ATC facility’s requirements. This allows controllers to effectively plan for transitions to adjacent FIRs.
4.6.4.4 You can find specific information regarding ATC separation standards in FAA Order JO 7110.65, Air Traffic Control. Additionally, trial periods where new separation standards are being applied will be announced on the FAA’s International Notices website.
4.7 Special Use Airspace (SUA).
4.7.1 Warning Area. A warning area, as defined in 14 CFR part 1, § 1.1, is airspace of defined dimensions extending from 3 NM outward from the coast of the United States that contains activity that may be hazardous to nonparticipating aircraft. The purpose of such a warning area is to warn nonparticipating pilots of the potential danger. A warning area may be located over domestic or international waters or both.
4.7.2 P rohibited Areas . ICAO Annex 2 specifies that these areas exist “above the land areas or territorial waters of a State, within which the flight of aircraft is prohibited.”
13 Regulatory reference is § 91.169, which refers to § 91.153. This requires the flight plan to include “any other information the pilot in command or ATC believes is necessary for ATC purposes.” The U.S. AIP states that pilots must “advise ATC” if equipment failures render the filed capability indicators inaccurate.