1-11-1. BASIC OCEANIC LONG-RANGE NAVIGATION AND COMMUNICATION REQUIREMENTS
a. Any operation which is conducted in international oceanic airspace on an IFR flight plan, a VFR controlled flight plan, or at night, and is continued beyond the published range of normal airways navigation facilities (NDB, VOR/DME), is considered to be a long-range Class II navigation operation. Long-range Class II navigation in Controlled Airspace (CTA) requires the aircraft to be navigated within the degree of accuracy required for air traffic control, meaning that the aircraft must follow the centerline of the assigned route, maintain the assigned altitude, and the speed filed or assigned. Accurate navigational performance is required to support the separation minima which air traffic control units apply. These separation minima can be found in the International Civil Aviation Organization (ICAO) Regional Supplementary Procedures Document 7030 and Air Traffic Control (FAA Order 7110.65).
b. Federal Aviation Regulation 14 CFR Part 91.1(b) requires that civil aircraft must comply with ICAO, Annex 2 when operating over the high seas. Annex 2 requires that ``Aircraft shall be equipped with suitable instruments and with navigation equipment appropriate to the route being flown.'' In addition, ICAO, Annex 6, Part II stipulates that an airplane operated in international airspace be provided with navigation equipment which will enable it to proceed in accordance with the flight plan and with the requirements of air traffic services. This means that the navigation equipment, installed and approved, should be capable of providing the pilot with the ability to navigate the aircraft with sufficient accuracy.
c. Annex 2 further requires that an aircraft shall adhere to the ``current flight plan unless a request for a change has been made and clearance obtained from the appropriate air traffic control facility.'' Annex 2, also requires that ``unless otherwise authorized or directed by the appropriate air traffic control unit, controlled flights shall, insofar as practicable: (a) when on an established ATS route, operate along the centerline of that route; or (b) when on another route, operate directly between the navigation facilities and/or points defining thatroute.'' In the event that a flight inadvertently deviates from the route on which it has been cleared, action shall be taken immediately to adjust the heading of the aircraft to rejoin the track as soon as possible. Furthermore, when a deviation from track is discovered, air traffic control must be informed so that appropriate actions may be taken to resolve any potential hazards to other aircraft which may have been created by the deviation. In contrast to operations in the domestic radar environment, operations in most oceanic areas are based on strategic clearance procedures, wherein separation depends on each aircraft navigating accurately. Any navigation error which results in an aircraft straying from the centerline of its cleared route and beyond its protected airspace could create a significant hazard, since the error would not normally be observed by air traffic control.
d. ICAO, Annex 6, Part II contains standards and recommended practices adopted as the minimum standards for all airplanes engaged in general aviation international air navigation. It requires that those airplanes operated in accordance with IFR, at night, or on a VFR controlled flight (such as in CTA/FIR Oceanic Airspace), have installed and approved radio communication equipment capable of conducting two-way communication at any time during the flight with such aeronautical stations and on such frequencies as may be prescribed by the appropriate authority.
e. All of the aforementioned requirements contained in Annex 2 (as supplemented by Regional Supplementary Procedures Document 7030 and Annex 6) are incorporated in 14 CFR Section 91.1 for those aircraft operating under United States civil certification in international oceanic airspace.
1-11-2. USE OF VERY HIGH FREQUENCY (VHF) AND HIGH FREQUENCY (HF) FOR COMMUNICATIONS
Due to the inherent line of sight limitations of VHF radio equipment when used for communications in international oceanic airspace, those aircraft operating on an IFR or controlled VFR flight plan beyond the communications capability of VHF willbe required, as per ICAO, Annex 2, to maintain a continuous listening watch and communications capability on the assigned HF frequencies. Although these frequencies will be designated by Air Traffic Control, actual communication will be with general purpose communication facilities such as international flight service stations or Aeronautical Radio, Inc. (ARINC). These facilities will be responsible for the relay of position reports and other pertinent information between the aircraft and Air Traffic Control.
1-11-3. SPECIAL NORTH ATLANTIC, CARIBBEAN AND PACIFIC AREA COMMUNICATIONS
a. VHF air-to-air frequencies enable aircraft engaged on flights over remote and oceanic areas out of range of VHF ground stations to exchange necessary operational information and to facilitate the resolution of operational problems.
b. Frequencies have been designated as follows:
|North Atlantic||131.80 MHz|
1-11-4. GUARD OF VHF EMERGENCY FREQUENCY
Pilots should remember that there is a need to continuously guard the VHF emergency frequency 121.5 MHz when on long over-water flights, except when communications on other VHF channels, equipment limitations, or cockpit duties prevent simultaneous guarding of two channels. Guarding of 121.5 MHz is particularly critical when operating in proximity to flight information region (FIR) boundaries, for example, operations on Route R220 between Anchorage and Tokyo, since it serves to facilitate communications with regard to aircraft which may experience in-flight emergencies, communications, or navigational difficulties.
ICAO Annex 10, Vol. II, Paragraphs 220.127.116.11.1.1 and 18.104.22.168.1.2
1-11-5. USE OF NON-DIRECTIONAL BEACON (NDB) FOR NAVIGATION
a. The use of an NDB as the primary source of navigation for long-range oceanic flight presents the operator with numerous limitations and restrictions that are inherent in low frequency radio equipment and the low frequency signals they receive. These include:
b. NDB navigation aids of the highest power (2000 or more watts) which are maintained and flight-checked as suitable for air navigation, but are limited in their usable service and/or reception range to no more than 75 nautical miles from the facility, at any altitude.
c. Although the operator may be able to receive standard amplitude modulation (AM) broadcast stations with NDB equipment, primary dependence on these facilities for air navigation is a questionable operating practice. The following are some of the inherent problems associated with reception of these stations:
1. Infrequent identification of the station.
2. Identification of foreign language stations may be impossible without some knowledge of the language.
3. Transmitter sites are not always collocated with studio facilities.
4. Termination of service without notice.
5. Weather systems causing erratic and unreliable reception of signal.
6. Atmospheric disturbances causing erratic and unreliable reception of signal.
7. No flight checks conducted to verify the suitability and reliability of the facility and its signal for use in air navigation.
8. Fluctuation (bending) of signal due to shoreline/mountain effect.
9. Standard broadcast stations are not dedicated for air navigation purposes.
d. Considering the aforementioned limitations, the operator should be able to navigate the aircraft so as to maintain the track/course and the tolerances specified in the Air Traffic Control Clearance (as per ICAO, Annex 2 and the Regional Supplementary Procedures Document 7030). Realizing that an error of 10 degrees, at a distance of 2000 miles, equates to approximately 350 miles of course deviation, the inadequacies of the non-directional beacon as the sole source of navigation for oceanic flight must be evaluated carefully.
1-11-6. FM INTERFERENCE
a. The International Civil Aviation organization (ICAO) has established standards which went into effect January 1, 1998, affecting requirements for aircraft ILS/VOR receivers and VHF communications systems. These standards call for these aircraft navigational and communications systems to meet new requirements for immunity from interference from FM broadcast signals. The new requirements address the potential for increased FM interference with these avionics systems beginning in 1998. The details of these standards are outlined in ICAO Annex 10, Volume I, Paragraphs 3.1.4 and 3.3.8, and Annex 10, Volume III, Paragraph 2.3.3.
b. Due to measures taken by the FAA and the FCC, the enhanced avionics equipage called for by the subject standards will not be required or necessary in the United States. Accordingly, the U.S. has notified ICAO of its intention not to implement these standards in U.S. controlled airspace. However, all operators are reminded of their responsibility to comply with the applicable regulations in force in the foreign airspace in which they operate, including any regulations requiring upgraded navigational and communications equipage compliant with the subject standards.