U.S . Department of Transportation Federal Aviation Administration Advisory Circular Subject: Oceanic and Remote Continental Airspace Operations Date: 4/3/25 AC No: 91-70D Initiated by: AFS-400 Change:
This advisory circular (AC) contains both general information and detailed guidance for operators planning flights in oceanic and remote continental airspace. This includes Performance-based Navigation (PBN) and Special Areas of Operation (SAO). The Federal Aviation Administration (FAA) revised this AC to focus on the evolving operations in oceanic and remote continental airspace. This AC is laid out in a building block format, beginning with foundational information, followed by information on the training, authorizations, and equipment required to operate most efficiently in this airspace, and finishing with flight planning, flight execution, and contingency operations guidance. Our goal is to provide you with a template to guide you through planning and executing flight operations through oceanic and remote continental airspace. Information related to international operations in specific locales continues to be available in the Regional Oceanic Resource Guides for U.S. Operators at https://www.faa.gov/about/officeorg/headquartersoffices/avs/oceanic-resource-guides. These online resource guides, along with Notices to Airmen (NOTAM) and FAA International Notices, provide the most current information available to pilots, aircraft dispatchers, and other operational control personnel preparing for oceanic and international operations. We have also included hyperlinks to many documents, available free or for purchase. While we carefully checked at the time of publication that information included in this AC is current, oceanic and remote continental airspace operations are constantly evolving, and it is incumbent on you, the operators, to ensure you are flying with current information.
This AC neither is mandatory, nor does it constitute a regulation. When this AC uses mandatory language (e.g., “must” or “may not”), it is quoting or paraphrasing a regulatory requirement or prohibition. When this AC uses permissive language (e.g., “should” or “may”), it describes an acceptable means, but not the only means, of conducting that aspect of operations in oceanic and remote continental airspace. However, if you use the means described in the AC, you must follow them in all important respects.
R obert H. Reckert for Robert M. Ruiz Acting Executive Director, Flight Standards Service
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CONTENTS Paragraph Page
Chapter 1. General1-1
1.1 Purpose of This Advisory Circular (AC)1-1
1.2 Audience1-1
1.3 Where You Can Find This AC1-1
1.4 What This AC Cancels1-1
1.5 Fundamental Changes From Previous Edition1-1
1.6 Related 14 CFR Parts1-1
1.7 Related Reading Material (current editions)1-2
1.8 AC Feedback Form1-3
Chapter 2. Background Information for Operations in Oceanic and Remote C
ontinental Airspace2-1
2.1 ICAO and its Relationship to U.S. Aviation2-1
2.2 ICAO Annexes2-1
2.3 Applicability of U.S. and International Regulations2-3
2.4 Differing Airspace Requirements2-7
2.5 Operational Authorizations2-8
2.6 ICAO Guidance Documents and Reference Material2-8
Chapter 3. P ilot Qualification and Training Guidance for Oceanic and Remote
Continental Airspace Operations3-1
3.1 Training Requirements for Oceanic and Remote Continental
Airspace Operations3-1
Chapter 4. Communications, Navigation, and Surveillance Systems Guidance for
Operations in Oceanic and Remote Continental Airspace4-1
4.1 Communications, Navigation, and Surveillance Improvements—Impact on
Air Traffic Service (ATS)4-1
4.2 Performance-Based Operations4-1
4.3 Voice Communications in Oceanic Airspace4-4
4.4 CPDLC and Automatic Dependent Surveillance-Contract (ADS-C)4-7
4.5 Data Link Systems—Operational Authorization to Use4-10
4.6 Independent Navigation Systems and Proceeding Safely4-10
4.7 ATC in Oceanic and Remote Continental Airspace4-12
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4.8 Special Use Airspace (SUA)4-14
4.9 Air Defense Identification Zones (ADIZ)4-15
4.10 World Geodetic System 1984 (WGS 84)4-15
Chapter 5. Flight Planning Guidance for International and Oceanic and Remote
Continental Airspace Operations5-1
5.1 Lead Time Requirements5-1
5.2 Preparing an Itinerary5-1
5.3 Crew Fatigue5-4
5.4 Required Paperwork/Documentation5-5
5.5 Entry to Foreign Airspace—Flight Plan vs. Formal Advance Permission5-7
5.6 Managing Risk in Oceanic and Remote Continental Airspace Operations5-7
5.7 Weather Forecasts and Other Meteorological Planning5-8
5.8 FAA International Notices Web Page5-8
5.9 ETOPS5-9
5.10 Polar Operations5-9
5.11 Areas With Limited or No ATS (Also Called “NO FIR” Areas)5-10
5.12 Rotorcraft Operations5-11
Ch apter 6. Flight Execution Guidance for Operations in Oceanic and Remote
Continental Airspace6-1
6.1 General Information6-1
6.2 Flight Plan6-5
6.3 Aircraft Preflight Guidance6-7
6.4 En Route Guidance6-14
Chapter 7. In-Flight Contingency Guidance for Operations in Oceanic Airspace7-1
7.1 Contingency Procedures: When They May Be Needed7-1
7.2 Choosing the Correct Contingency Procedure7-1
7.3 Altimetry and/or Navigation Degradation7-2
7.4 Lost Communications Procedures7-2
7.5 Normal Aircraft Tracking7-3
Appe ndix A. Abbreviations and DefinitionsA-1
Appe ndix B. O perational Authorizations: 14 CFR Part 91 LOAsB-1
Appe ndix C. Unusual W eather ActivityC-1
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Appendix D. S ample Oceanic ChecklistD-1
Appe ndix E. IATA In-Flight Broadcast ProcedureE-1
Appe ndix F. S pecial Procedures for In-Flight Contingencies in Oceanic AirspaceF-1
Appe ndix G. Suggested S ubjects for Inclusion in Oceanic and International Procedures
and/or an Operations ManualG-1
L ist of Figures
Figure 4-1. Sample CPDLC Route Uplinks4-9
Figure 6-1. S ample Plotting Chart6-9
Figure 6-2. AR INC 424—Oceanic Waypoints6-11
Figure C-1. I CAO Volcanic Ash Advisory CentersC-1
Figure C-2. E xample of a National Oceanic and Atmospheric Administration Scales
Activity ReportC-3
Figure E-1. M ap of IFBP Area of ApplicabilityE-2
Figure F-1. S pecial Procedures for In-Flight Contingencies in Oceanic Airspace
(Non-Weather)F-1
Figure F-2. S pecial Procedures for In-Flight Weather ContingenciesF-6
L ist of Tables
Table 2-1. Regulatory References With Distances From the Nearest Shoreline2-5
Table 2-2. O verwater Airspaces and Interrelationships2-7
Table 6-1. E xamples of Incorrectly Applied Conditional Clearances6-2
Table 6-2. S elected Waypoint Entry Methods and Avionics Display6-3
Table B-1. T itle 14 CFR Part 91 LOAs for Oceanic and/or Remote AreasB-3
Table F-1. A ltitude Offset When Denied Clearance to Deviate 9.3 km (5.0 NM) or More
(5 NM Procedures)F-7
1-1 CHAPTER 1. GENERAL
1.1 Purpose of This Advisory Circular (AC). The Federal Aviation Administration (FAA) (“we”) developed this AC to provide general information and guidance for certificated and General Aviation (GA) operators (“you”) planning flights in oceanic and remote continental airspace. The principal regulatory reference for this guidance is Title 14 of the Code of Federal Regulations (14 CFR) § 91.703, which incorporates International Civil Aviation Organization (ICAO) Annex 2, Rules of the Air, by reference. ICAO Annex 2, in turn, refers to ICAO Doc 7030, which requires State of the Operator or State of Registry approval for oceanic Required Navigation Performance (RNP) operations. This guidance includes the authorizations you may need for operations in such airspace. The contents of this document do not have the force and effect of law and are not meant to bind the public in any way, and the document is intended only to provide information to the public regarding existing requirements under the law or agency policies.
1.2 Audience. We wrote this AC primarily for operators who do not have experience with flying in oceanic and remote continental airspace, to assist in developing their own procedures. We also wrote this AC for GA pilots who do not fly regularly in oceanic and remote continental airspace and need a refresher in planning and executing such a flight.
Most certificated operators have company procedures for operations in oceanic and remote continental airspace. Those procedures have been accepted by FAA inspectors and conform to all relevant regulations and guidance. If you are working for one of these operators, this AC may serve to reinforce your company procedures.
1.3 Where You Can Find This AC. You can find this AC on the FAA’s website at https://www.faa.gov/regulations_policies/advisory_circulars and the Dynamic Regulatory System (DRS) at https://drs.faa.gov.
1.4 What This AC Cancels. AC 91-70C, Oceanic and Remote Continental Airspace Operations, dated October 4, 2023, is canceled.
1.5 Fundamental Changes From Previous Edition. This revision of AC 91-70 adds clarifications on navigation equipment regulations and “proceeding safely,” and includes new guidance on dead reckoning. Also, we have adjusted Appendix D, Sample Oceanic Checklist, in light of the removal of separate oceanic clearances in the North Atlantic (NAT).
1.6 Related 14 CFR Parts.
• Sections 91.1 through 91.21, 91.101 through 91.143, 91.151 through 91.159, 91.167 through 91.193, 91.203, 91.205, 91.209 through 91.217, 91.221, 91.225, 91.227,
91.303 through 91.319, 91.323, 91.509, 91.511, 91.605, 91.609, 91.703 through
91.715, 91.903, 91.1039, and 91.1073; and appendix G.
• Sections 119.5, 119.49, 119.59, and 119.63.
• Sections 121.11, 121.101, 121.121, 121.163, 121.339, 121.349, 121.351, 121.353,
121.355, 121.401, 121.415, 121.427, and 121.445; and appendix G.
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• Sections
125.23 ,
125.45 ,
125.51 ,
125.203 ,
125.209 ,
125.296 , and
125.363 .
• Sections 135.3, 135.43, 135.145, 135.165, 135.167, 135.183, 135.213, 135.323,
135.329, 135.351, 135.364, and 135.381; and appendix G.
1.7 Related Reading Material (current editions).
1.7.1 RTCA Documents. Available for purchase on the RTCA website at https://www.rtca.org/standards.
1. RTCA DO-258/ED-100, Interoperability Requirements for ATS Applications Using ARINC 622 Data Communications.
2. RTCA DO-260/ED-102, Minimum Operational Performance Standards (MOPS) for 1090 MHz Extended Squitter Automatic Dependent Surveillance – Broadcast (ADS-B) and Traffic Information Services – Broadcast (TIS-B).
3. RTCA DO-306/ED-122, Safety and Performance Standard for Air Traffic Data Link Services in Oceanic and Remote Airspace (Oceanic SPR Standard).
4. RTCA DO-350/ED-228, Safety and Performance Requirements Standard for Baseline 2 ATS Data Communications (Baseline 2 SPR Standard).
1.7.2 FAA Technical Standard Orders (TSO). Available at https://drs.faa.gov.
1. TSO-C115, Required Navigation Performance (RNP) Equipment Using Multi-Sensor Inputs.
2. TSO-C145, Airborne Navigation Sensors Using the Global Positioning System Augmented by the Satellite Based Augmentation System (SBAS).
3. TSO-C146, Stand-Alone Airborne Navigation Equipment Using the Global Positioning System Augmented by the Satellite Based Augmentation System (SBAS).
4. TSO-C196, Airborne Supplemental Navigation Sensors for Global Positioning System Equipment Using Aircraft-Based Augmentation.
1.7.3 FAA ACs.
1. AC 20-138, Airworthiness Approval of Positioning and Navigation Systems.
2. AC 20-140, Guidelines for Design Approval of Aircraft Data Link Communication Systems Supporting Air Traffic Services (ATS).
3. AC 20-150, Airworthiness Approval of Satellite Voice (SATVOICE) Equipment Supporting Air Traffic Service (ATS) Communication.
4. AC 90-80, Approval of Offshore Standard Approach Procedures, Airborne Radar Approaches, and Helicopter En Route Descent Areas.
5. AC 90-96, Approval of U.S. Operators and Aircraft to Operate Under Instrument Flight Rules (IFR) in European Airspace Designated for Basic Area Navigation (B-RNAV)/RNAV 5 and Precision Area Navigation (P-RNAV).
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6. AC 90-105 , Approval Guidance for RNP Operations and Barometric Vertical Navigation in the U.S. National Airspace System and in Oceanic and Remote Continental Airspace.
7.
AC 90-114, Automatic Dependent Surveillance-Broadcast Operations.
8. AC 90-117, Data Link Communications.
9. AC 91-85, Authorization of Aircraft and Operators for Flight in Reduced Vertical Separation Minimum (RVSM) Airspace.
10. AC 91-92, Pilot’s Guide to a Preflight Briefing.
11. AC 120-42, Extended Operations (ETOPS and Polar Operations).
12. AC 120-100, Basics of Aviation Fatigue.
13. AC 120-103, Fatigue Risk Management Systems for Aviation Safety.
14. AC 121-31, Flightcrew Sleeping Quarters and Rest Facilities.
15. AC 135-42, Extended Operations (ETOPS) and Operations in the North Polar Area.
1.7.4 FAA Instrument Flight Rules (IFR) Enroute Aeronautical Planning Charts. These charts are available at https://www.faa.gov/air_traffic/flight_info/aeronav/digital_products/ifr.
1. North Atlantic Route Chart.
2. North Pacific Route Chart.
3. Western Atlantic Route System Chart.
1.8 AC Feedback Form. For your convenience, the AC Feedback Form is the last page of this AC. Note any deficiencies found, clarifications needed, or suggested improvements regarding the contents of this AC on the AC Feedback Form.
2-1 CHAPTER 2. BACKGROUND INFORMATION FOR OPERATIONS IN OCEANIC
AND REMOTE CONTINENTAL AIRSPACE
2.1 ICAO and its Relationship to U.S. Aviation. The United States is a Contracting State to the Convention on International Civil Aviation (Chicago Convention) and an ICAO Member State and has fully supported the organization’s goals from its inception. ICAO works to achieve the highest level of standards and procedures for aircraft, personnel, airways, and aviation services throughout the world. ICAO oversees the international standards ascribed to by its more than 190 Member States for navigation facilities, airports, weather, and radio services. Through active support and participation in ICAO, the FAA strives to improve worldwide safety standards and procedures. ICAO’s strategic objectives are to continue to establish and maintain Standards and Recommended Practices (SARPs) for the safe and orderly development of international aviation. The 19 Annexes to the Chicago Convention (ICAO Annexes) contain more than 10,000 adopted SARPs.
Note: ICAO Member States are obligated to “collaborate in securing the highest practicable degree of uniformity in regulations” and generally achieve this by complying with the SARPs contained in the 19 Annexes and supporting ICAO documents, such as ICAO Doc 4444, Procedures for Air Navigation Services— Air Traffic Management (PANS-ATM), and ICAO Doc 7030, Regional Supplementary Procedures (SUPPS). States notify ICAO of their “differences” with SARPs and publish them in their Aeronautical Information Publication (AIP).
2.2 ICAO Annexes. Find all ICAO Annexes at the ICAO store at https://store.icao.int or at the ICAO eLibrary at https://elibrary.icao.int.
2.2.1 Annex 1, Personnel Licensing. Provides information on licensing of flightcrews, air traffic controllers, and aircraft maintenance personnel, including medical standards for flightcrews and air traffic controllers.
2.2.2 Annex 2, Rules of the Air. Contains visual flight rules (VFR) and instrument flight rules (IFR) for all operators.
2.2.3 Annex 3, Meteorological Service for International Air Navigation. Provides for meteorological services for international air navigation and reporting of meteorological observations from aircraft.
2.2.4 Annex 4, Aeronautical Charts. Contains specifications for aeronautical charts used in international aviation.
2.2.5 Annex 5, Units of Measurement to be Used in Air and Ground Operations. Lists dimensional systems used in air and ground operations.
2.2.6 Annex 6, Operation of Aircraft (3 Parts). Specifies minimum standards for below-listed operations throughout the world:
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1. Part I, International Commercial Air Transport—Aeroplanes.
2. Part II, International General Aviation—Aeroplanes.
3. Part III, International Operations—Helicopters.
2.2.7 Annex 7, Aircraft Nationality and Registration Marks. Specifies requirements for registration and identification of aircraft.
2.2.8 Annex 8, Airworthiness of Aircraft. Specifies uniform procedures for certification and inspection of aircraft.
2.2.9 Annex 9, Facilitation. Provides for the standardization and simplification of border-crossing formalities.
2.2.10 Annex 10, Aeronautical Telecommunications:
1. Volume I, Radio Navigation Aids. Provides for standardizing communications equipment and systems.
2. Volume II, Communication Procedures including those with PANS status.
Standardizes communications procedures.
3. Volume III, Communication Systems. Standardizes communications systems.
4. Volume IV, Surveillance and Collision Avoidance Systems. Standardizes surveillance radar and collision avoidance.
5. Volume V, Aeronautical Radio Frequency Spectrum Utilization. Standardizes aeronautical radio spectrum utilization.
6. Volume VI, Communication Systems and Procedures Relating to Remotely Piloted Aircraft Systems C2 Link (applicable November 26, 2026).
2.2.11 Annex 11, Air Traffic Services. Includes information on establishing and operating air traffic control (ATC), flight information, and alerting services.
2.2.12 Annex 12, Search and Rescue. Provides information on organization and operation of facilities and services necessary for Search and Rescue (SAR).
2.2.13 Annex 13, Aircraft Accident and Incident Investigation. Provides for uniformity in notifying, investigating, and reporting on aircraft accidents.
2.2.14 Annex 14, Aerodromes:
1. Volume I, Aerodrome Design and Operations. Contains specifications for the design and equipment of aerodromes.
2. Volume II, Heliports. Contains specifications for the design and equipment of heliports.
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2.2.15 Annex 15, Aeronautical Information Services. Includes methods for collecting and disseminating aeronautical information required for flight operations.
2.2.16 Annex 16, Environmental Protection:
1. Volume I, Aircraft Noise. Contains specifications for aircraft noise certification, noise monitoring, and noise exposure units for land-use planning.
2. Volume II, Aircraft Engine Emissions. Contains specifications for aircraft engine emissions.
3. Volume III, Aeroplane CO2 Emissions.
4. Volume IV, Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA).
2.2.17 Annex 17, Aviation Security. Specifies methods for safeguarding international civil aviation against unlawful acts of interference.
2.2.18 Annex 18, The Safe Transport of Dangerous Goods by Air. Contains specifications for labeling, packing, and shipping dangerous cargo.
2.2.19 Annex 19, Safety Management. Describes Safety Management System (SMS) development, regulatory framework, and supporting guidance.
2.3 Applicability of U.S. and International Regulations.
2.3.1 FAA regulations relating to certification, airworthiness, licensing, and certain operational aspects (e.g., operational control, communication and navigation equipment, and Extended Operations (ETOPS)) are applicable to U.S. operators wherever they fly. Some of these regulations are fundamental to oceanic operations:
2.3.1.1 Title 14 CFR § 91.511 (applicable to 14 CFR part 91 subpart F) deals with “overwater” operations which are more than 30 minutes or 100 nautical miles (NM) from the nearest shore.
Note: Title 14 CFR § 91.511(b) notes that a unit is “independent if the function of any part of it does not depend on the functioning of any part of another receiver or electronic navigation unit.”
2.3.1.1.1 For such operations, two independent long-range navigation systems (LRNS) are required, except in an area defined by coordinates in 14 CFR § 91.511(f), where only one LRNS is sufficient.
2.3.1.1.2 Title 14 CFR part 91 subpart F overwater operations outside very high frequency (VHF) voice communication coverage require two long-range communication systems (LRCS), except when an aircraft has two VHF radios, in which case only one high frequency (HF) radio is sufficient.
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2.3.1.2 Title 14 CFR §§ 121.351, 125.203, and 135.165 use a different term, extended overwater operations, defined in 14 CFR § 1.1 as more than 50 NM from the nearest shoreline.
2.3.1.2.1 Title 14 CFR § 121.351 specifically requires two “independent long-range navigation systems” for extended overwater operations.
2.3.1.2.2 Title 14 CFR §§ 125.203 and 135.165 use different language, and only require “two approved independent navigation systems suitable for navigating the airplane along the route” within the “degree of accuracy required for ATC.”
This allows extended overwater operations along Air Traffic Services (ATS) routes that have ground-based Navigational Aid (NAVAID) coverage, without any LRNS.
2.3.1.2.3 For 14 CFR parts 121, 125, and 135, extended overwater operations “in certain geographic areas” with only a single LRNS can be authorized via the B036 authorization.1 1 FAA operational authorizations (specific approvals) are given in the form of operations specifications (OpSpecs), management specifications (MSpecs), or Letters of Authorization (LOAs). For simplicity in this AC, we use the term “authorization.”
2.3.1.2.4 E xtended overwater operations outside VHF voice communication coverage require two LRCSs, except for certificated operators who hold the B045 authorization which defines an area by coordinates where only one LRCS is sufficient.
2.3.2 Similarly, some regulations applicable to U.S. operators wherever they fly are fundamental to operations outside ground-based NAVAID coverage, where an LRNS is used. The following are regulatory considerations inherent to those operations:
2.3.2.1 Title 14 CFR §§ 121.349, 125.203, and 135.165 use the term “proceed safely” in the event of loss of navigation capability of the system being used to navigate to the degree of accuracy for ATC, in the context of fuel planning and operations with a “single independent navigation system.”
2.3.2.2 These sections require there to be “at least one other independent navigation system suitable…for proceeding safely to a suitable airport and completing an instrument approach…” A compass and a stopwatch comprise a very rudimentary independent navigation system that is not suitable for navigating within the degree of accuracy required for ATC.
2.3.2.3 However, if flightcrews are properly trained, a compass and a stopwatch can be used together with an operational flight plan to dead reckon. In an unexpected failure situation, dead reckoning can be a valid method to proceed safely. The sections cited above require that the other navigation system be suitable to “complete an instrument approach,” which normally would be an
2-5 instrument landing system (ILS) approach. Additional considerations about dead reckoning are discussed in Chapter 4.
Note: The guidance above pertains to being able to proceed safely when operating with a single independent navigation system that experiences a failure. Equipping an aircraft with multiple independent navigation systems gives operators additional options in unexpected failure situations.
2.3.3 Table 2-1 below provides a listing of select regulations that apply at various distances from the coast of the United States or from the “nearest shoreline.” The table lists some of these regulations and the distance from the coast where they apply. Note that 14 CFR § 91.101 applies to all aircraft, but regulations referencing 50 NM and 100 NM apply to U.S.-registered civil aircraft. The listing is not exhaustive.
Table 2-1. Regulatory References With Distances From the Nearest Shoreline Distance From the Coast/Nearest Shoreline2 Title 14 CFR Reference Remarks ≤ 12 NM from coast of the United States § 91.101 • Title 14 CFR part 91 subpart B applies for operation of aircraft “within 12 nautical miles from the coast of the United States.”
• Waters up to and including 12 NM are generally “territorial waters,” which underly “sovereign airspace.”
> 12 NM from coast § 91.7033 • Title 14 CFR § 91.703 applies “outside of the United States” and requires compliance with ICAO Annex 2 “when over the high seas.”
• The United Nations Convention on the Law of the Sea (UNCLOS) allows coastal states to exercise sovereignty over their “territorial seas” up to a limit not to exceed 12 NM.
• Beyond 12 NM is where “high seas” (international) airspace generally begins and where ICAO Annex 2 (regulating “flight and maneuver”) applies.
> 50 NM from nearest shoreline § 1.1, Definition of Extended Overwater Operation Communications and navigation equipment:
• Title 14 CFR § 121.351.
• Title 14 CFR § 125.203.
• Title 14 CFR § 135.165.
Emergency equipment:
• Title 14 CFR § 121.339.
• Title 14 CFR § 125.209.
2 The term “coast” applies to oceans, whereas the term “shore” or “shoreline” applies to oceans and lakes.
3 Title 14 CFR §§ 125.23 and 135.3 both also refer to 14 CFR § 91.703, which incorporates ICAO Annex 2 by reference.