CHAPTER 6. FLIGHT EXECUTION GUIDANCE FOR OPERATIONS IN OCEANIC
AND REMOTE CONTINENTAL AIRSPACE
6.1 General Information.
6.1.1 Checklists. In Appendix D, Sample Oceanic Checklist, we have included a sample oceanic checklist tailored from the ICAO version, in both condensed and expanded forms. The checklist is designed to encourage an orderly task flow and reduce oceanic vertical, lateral, longitudinal, and timing navigation errors.
Note: You may tailor the expanded checklist to your specific needs and approvals. During actual operations, refer to that tailored expanded checklist to ensure you follow the procedures in their entirety.
6.1.2 Pilot Deviations—Common Causes.
6.1.2.1 Technological advances in communications, navigation, and surveillance equipment have enabled aircraft to operate with ever-improving precision and accuracy. However, despite this increased navigational capability, pilots continue to deviate from their current route clearances.
6.1.2.2 A Large Height Deviation (LHD) occurs when an aircraft is 300 feet or more off its assigned altitude. LHDs increase the risk of mid-air collision.
6.1.2.2.1 The most common causes of LHDs are:
1. Air traffic control (ATC) loop errors:
• Misunderstood clearances.
• Lack of proper ATC coordination procedures.
2. Pilot deviations from assigned altitude:
• Following the flight plan rather than a clearance or reclearance.
• Erroneous altitude programming in the flight management system (FMS), such as a mistake in the step-climb entry.
• Misinterpretation/misapplication of conditional clearances.
• Improper execution of pilot contingency procedures.
• Turbulence encounters.
6.1.2.2.2 Collected data indicates that a majority of crew-related errors involve misinterpretation or misapplication of “conditional clearances.” Conditional clearances improve the efficient utilization of airspace, allowing ATC to assign altitudes that enable lower fuel burn. Event reports from ATC and flightcrews indicate that pilots misapply terms in the clearance such as “BY” or “AT”—terms, which have completely different meanings. See Table 6-1 below for examples of incorrectly applied conditional clearances.
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Table 6-1. Examples of Incorrectly Applied Conditional Clearances
CLEARANCE CREW ACTION CORRECT ACTION Via CPDLC at 1714, crew conditionally cleared, “maintain F340, at 1725 climb to and maintain F360, climb to reach F360 by 1735, report level, due to traffic.”
Crew initiated climb early, reported (ADS-C) passing F354 at 1721.
Crew should have delayed commencing climb until 1725, and planned to reach F360 by 1735.
Via CPDLC, crew cleared 66/30 66/40 65/50 F380 M081, cleared F390 to cross 66/40 level.
Crew commenced climb to F390 at 40W (Mode C).
Crew should have initiated climb prior to 40W in order to cross 40W at F390.
Via CPDLC at 1945, crew cleared maintain F330, at 1952 climb to and maintain F350, climb to reach F350 by 1957, report level F350.
Reported (ADS-C) level at F350 at 1948.
Crew should have delayed commencing climb until 1952, and planned to reach F350 by 1957.
Crew cleared 68/40 64/50 IRBIM F360 M083 via HF voice, crew recleared to descend after passing 65N to be level F340 before 64N.
Crew commenced descent at 6529N/4650W.
Crew should have initiated descent after passing 65N and levelled at F340 prior to 64N.
Crew cleared 66/30 65/40 63/50 IRBIM LOMTA F400 M081. Via CPDLC, crew cleared climb F410 to cross 65/40 level.
Crew failed to climb as cleared and crossed 65/40 at F400 (ADS-C).
Crew should have initiated climb prior to 65N in order to cross 65N at F410.
6.1.2.2.3 Your training program should provide you and your crew with procedures that ensure all ATC clearances are complied with correctly, particularly clearances with en route restrictions such as changing flight levels (FL) based on a coordinated time or a specific geographic position.
Note: Per ICAO NAT Document 007, when flying in North Atlantic (NAT) airspace, you must immediately report to ATC when leaving and reaching a new FL. Doing so can enable the controller to identify and intervene when you have misunderstood or misapplied your conditional clearance.
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6.1.2.3 ICAO identifies gross navigation errors (GNE) as lateral deviations from course of 25 nautical miles (NM) or greater. In the North Atlantic, the threshold is 10 NM.
6.1.2.3.1 The majority of today’s GNEs arise from pilots flying a very precise track to the wrong position because they failed to properly update their FMS to reflect their currently effective route clearance. This can also result from a clearance or reclearance that was incorrectly entered, misread, or misunderstood. Procedures to follow in the event of a reclearance are included in paragraph 6.4.1.6. Examples of scenarios that have led to GNEs are:
1. Poor management of the master document, resulting in crews not knowing the currently effective route clearance.
2. Incorrect waypoint entry procedures, particularly if the waypoints are not named and flightcrews must enter the full latitude and longitude.
Note: Waypoints entered via full latitude and longitude can produce misleading display names, where minutes are truncated or rounded and/or generic names are generated.
6.1.2.3.2 GNEs also result when the aircraft navigation mode is actually different from that assumed by the crew. This scenario typically occurs when the crew fails to return to “LNAV” (lateral navigation) after utilizing “heading select” to maneuver the aircraft.
6.1.2.3.3 Although there are a number of causes of GNEs, pilot inattention has been the root cause of many navigational errors. ICAO NAT Document 007, in a chapter titled Guarding against Complacency, provides excellent lessons learned from evaluation of GNE incidents.
6.1.2.4 Longitudinal errors, in the form of failure to provide updated estimated times of arrival (ETA), are another common navigation error and one that is easily preventable.
6.1.2.4.1 Deviations around weather can affect ETAs. It is important to remember that even when ATC clears you to deviate, the onus is on the pilot to update the ETA as appropriate.
6.1.2.4.2 You must adhere to your assigned (true) Mach number. If you use Long Range Cruise or Economy (ECON) modes to travel in speed-controlled airspace, you are operating in a constantly changing speed mode. Flying in these modes may not be compatible with the strict tolerances required for ATC’s longitudinal separation of aircraft.
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6.1.2.4.3 When position reports are made by voice, ICAO requires you to report to ATS authorities any change to your ETA in excess of 2 minutes, both for your initial oceanic entry point as well as all required reporting points along your route of flight through oceanic and remote continental airspace.
6.1.2.4.4 Discrepant wind data can result in inaccurate ETA computations. This can be particularly problematic if you are not flying at the flight-planned altitude or have outdated winds loaded in your FMS. You must diligently monitor your ETA and maintain your assigned Mach number in order to minimize these errors.
6.1.2.4.5 FMS-computed ETAs, particularly for more distant waypoints, may be erroneous due to down track wind conditions, which the FMS is not presently using to compute the ETA. You should compare FMS estimates with the ETA calculated on the operational flight plan prior to reporting the ETA to ATC facilities.
6.1.2.4.6 Automatic position reports delivered via Automatic Dependent Surveillance-Contract (ADS-C) have greatly reduced the occurrence of longitudinal errors caused by inaccurate ETAs. ATC establishes an ADS-C periodic report interval appropriate for the longitudinal and lateral separation criteria being used. More frequent reports compensate for wind discrepancies and provide ATC with accurate ETAs.
6.2 Flight Plan.
6.2.1 ATC Flight Plan.
6.2.1.1 ICAO requires a flight plan for all flights that cross international borders.
Instrument flight rules (IFR) operations in oceanic airspace generally start at 6,000 feet. Visual flight rules (VFR) operations at or below 5,500 feet must comply with all applicable regulations and foreign airspace requirements.
6.2.1.1.1 Even though you may legally conduct flights in oceanic and remote continental airspace under VFR, there is generally a good likelihood of encountering instrument meteorological conditions at some point in your flight.
6.2.1.1.2 We highly recommend that you file an IFR flight plan on any oceanic flight, if you are instrument rated and your aircraft meets the equipment requirements for IFR flight.
6.2.1.2 Proper completion of an ATC flight plan requires that you have detailed knowledge of the airspace you intend to transit, the airspace equipment requirements, and the required FAA authorizations (operations specifications (OpSpecs)/management specifications (MSpecs)/letters of authorization (LOA)). You also need to be thoroughly familiar with the equipment your aircraft has on board as listed in your filed flight plan. When you file, your 6-4
flight plan is transmitted to ATS facilities along the route of flight. If you do not file correctly, you could possibly experience delays before takeoff for an issue with an ATS authority along your route of flight.
6.2.1.2.1 The Aeronautical Information Manual (AIM) has a step-by-step description in Chapter 5 detailing how to complete FAA Form 7233-4, Pre-Flight Checklist and International Flight Plan.
6.2.1.2.2 Additionally, ICAO NAT Document 007 provides an indepth discussion on completing the flight plan, with special attention given to operating in NAT airspace, in its attachment 4, ICAO FPL Completion for a NAT Flight.
6.2.1.2.3 Both documents take you step by step through each entry in the flight plan form, including the special descriptors that will identify to ATS authorities your equipment and authorizations.
6.2.1.3 As Performance-based Navigation (PBN) becomes more prevalent worldwide, ATS authorities will increasingly set aside certain airspace for PBN-compliant aircraft. You list your aircraft and crew capabilities using descriptors in items 10A, 10B, and 18 of the flight plan.
Note: Without the proper codes or remarks identifying the operational approvals of your crew and aircraft, controllers may deny you en route climbs to your most fuel-efficient FLs or access to the optimum routings or, in some cases, reject your flight plan entirely.
6.2.1.4 Title 14 CFR part 121 dispatch services are required to have staff knowledgeable in all filing requirements for both domestic and international operations. These services can support flight plan reroutes that may arise due to weather or congestion along your route of flight. If you are operating without the benefit of a dispatch service, you must have the knowledge and necessary tools available to react to unplanned reroutes, equipment failures, or emergencies that may impact your flight while en route.
6.2.2 Equipment Capability Codes—Flight Plan.
6.2.2.1 PBN is changing the way ATS providers apply separation criteria between aircraft. Without notifying the crew of either aircraft involved, ATS providers in “mixed mandate” airspace can reduce separation between aircraft based on your stated capability. In order to take advantage of opportunities for more efficient routings, your flight plan should reflect the lowest Required Navigation Performance (RNP) value for which you are capable and authorized.
6.2.2.2 Upon entering oceanic and remote continental airspace, the RNP setting in your flight management computer (FMC) must be equal to or less than that required for the route of flight, and it should reflect the RNP capability 6-5
indicated on your flight plan. If you indicate RNP 4 capability on the flight plan, for example, ATC could establish separation criteria for your flight based on RNP 4 capability, even though only RNP 10 is required for the route of flight. Likewise, if RNP 10 is required for the route, the FMC setting must be no higher than 10.0. A higher setting will prevent your navigation system’s RNP performance monitoring and alerting capability, as well as the lateral deviation scaling, from functioning according to the RNP requirements for your route of flight. In such a scenario, a loss of required aircraft separation could ensue. The RNAV/RNP capability indicated on your flight plan must not be less than that for which you have been approved via an OpSpec, MSpec, or LOA.
6.2.2.3 If you are no longer able to meet your RNP navigation specification while en route (i.e., your Actual Navigation Performance (ANP) exceeds your RNP or required equipment has failed), you are required to immediately notify your ATS provider so they can adjust separation standards between you and other nearby aircraft as required.
6.3 Aircraft Preflight Guidance.
6.3.1 Preflight—Necessary Documents. Effective oceanic and remote continental airspace flight planning and execution requires a number of important pieces of information.
You should ensure you have easy access to each of the following documents in the cockpit, as well as others that may be pertinent to your flight:
6.3.1.1 Master flight plan (“master document”).
Note: Use strict procedures to manage the master document. Maintain only one copy of the master document in the cockpit.
6.3.1.2 Notices to Airmen (NOTAM) for departure, destination, alternate(s), Extended Operations (ETOPS) alternates (as applicable), and oceanic Flight Information Regions (FIR).
6.3.1.3 Global Positioning System (GPS) NOTAMs (as applicable).
6.3.1.4 Weather for departure, destination, alternate airports along the route of flight, and ETOPS alternates (as applicable).
6.3.1.5 Significant weather (SIGWX) chart.
6.3.1.6 Wind charts for planned altitudes and altitudes after drift-down/emergency descent.
Note: Compute equal time points (ETP) for contingencies, such as medical divert, engine loss, rapid decompression (RD), and a simultaneous RD and engine loss. Note the location of the ETPs on your chart.
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6.3.1.7 Volcanic ash and solar flare information (as applicable).
6.3.1.8 Pilot Weather Reports (PIREP).
6.3.1.9 Receiver autonomous integrity monitoring (RAIM) and fault detection and exclusion (FDE) prediction (as applicable).
6.3.1.10 Current track message (for any operations in airspace with a flexible organized track system).
Note: If you have a track message or other separate route document associated with the flight, verify that the effective time of the message corresponds to your flight and that the designated route agrees with both your filed routing and the waypoint routing on your master document.
6.3.1.11 Plotting/orientation chart.
6.3.1.11.1 You should use a chart, of appropriate scale, to provide yourself with a visual presentation of your intended route, regardless of your type(s) of long-range navigation system (LRNS). Plotting your route on your chart will increase your situational awareness as you execute your trip through oceanic and remote continental airspace.
6.3.1.11.2 Your chart should include, at a minimum:
1. The route of your filed flight plan or currently effective route clearance.
2. Clearly depicted waypoints using standardized symbology.
3. Graphic depictions of all ETPs.
4. Alternate airports.
5. Proximity of other adjacent tracks.
Note: For certificated operators, if OpSpec/MSpec A061 has been issued authorizing use of an Electronic Flight Bag (EFB) and the principal inspector (PI) has authorized “interactive plotting for oceanic and remote continental navigation,” the EFB application may be used in place of a paper plotting/orientation chart. The current edition of AC 120-76, Guidelines for the Certification, Airworthiness, and Operational Approval of Electronic Flight Bags, provides guidance for operators to develop associated EFB procedures. For part 91 operators, an EFB may be used, provided the criteria and considerations of the current edition of AC 91-78, Use of Class 1 or Class 2 Electronic Flight Bag (EFB), are observed.
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6.3.2 Cockpit Preparations.
6.3.2.1 Check your maintenance log to ensure all your required communications, navigation, and surveillance and altimetry equipment is operational in order to enter oceanic and remote continental airspace.
1. If you are faced with faulty aircraft equipment, such as your long-range navigation equipment or a central air data computer fault, notify ATC as soon as possible. ATC will more than likely increase spacing around an aircraft with degraded capabilities.
2. Consult your minimum equipment list (MEL) to resolve malfunctioning equipment before you depart. A departure delay for maintenance may be warranted or a reroute to avoid oceanic airspace may be necessary.
6.3.2.2 Identify a single master clock in the cockpit.
1. You must verify that your onboard primary time source, or master clock, is set to Coordinated Universal Time (UTC). In most cases, this time source is the FMS.
2. Use master clock times for all ETAs and actual times of arrival (ATA).
6.3.2.3 Align your inertial navigation system (INS)/inertial reference system (IRS).
1. Proper INS/IRS loading and operating procedures are another important aspect to help you avoid navigation errors. Ensure you select navigation (NAV) mode at the appropriate time and properly manage your navigation computer during intermediate stops.
2. Follow your flight manual procedures carefully to ensure proper navigation reliability.
6.3.2.4 Have a second pilot independently verify the aircraft present position coordinates you have loaded in your navigation system.
1. Regardless of your type of LRNS or the method of insertion, you must verify your current ramp position in the LRNS against current aeronautical publications and not solely based on the present position remaining in the system from your last shutdown.
2. If you conduct another present position check on taxi out and it shows a gross difference with your gate coordinates, it could indicate a problem with the LRNS.
6.3.2.5 Two pilots should independently coordinate the loading and verification of all flight plan entries. One pilot should load the entire route into the LRNS, to include all waypoints, using the master document as source. He or she 6-8
should then verify the routing has been loaded correctly. Recommended steps for performing this loading and verification are provided immediately below.
The second pilot’s subsequent confirmation procedures are explained beginning in paragraph 6.3.2.6.
6.3.2.5.1 Prior to loading the flight plan, carefully cross-check the waypoint routing on your master document against your filed flight plan to verify both documents show the same routing.
6.3.2.5.2 Ensure your navigation database is current.
6.3.2.5.3 For systems with pilot-defined waypoint designators or numbers, we recommend you use a consistent procedure from the outset of the flight.
Enter this designator on the master document and also use it to store waypoints in the navigational computer.
6.3.2.5.4 You must verify all navigational information contained in the master document against the navigation data information in the FMS.
6.3.2.5.5 Your procedures should provide for a means of verification of the data you loaded. You should check the expanded coordinates and course/distance between waypoints against the same information on your master document.
You may also check the route presentation on your navigation display. Most intercontinental-capable aircraft have a modern FMS that is capable of automatically downloading flight plans that have been sent from ATC or from a dispatch service. These flight plan transmission mechanisms are very reliable, but there are occasional glitches that can lead to downloading partial routes, requiring you to make changes to complete the route load.
Regardless of whether you have an automatic or manual download of your flight plan into your FMS, you should have procedures to verify your flight plan route against your FMS entries.
6.3.2.6 After the first pilot has loaded and verified the FMS entries against the flight plan, a second pilot should recall and confirm the waypoint data against source information.
6.3.2.6.1 It is not sufficient for one crewmember to simply observe another crewmember entering the data. Exercise an independent cross-check method with each other so no FMS entry goes unverified. An attitude of “healthy suspicion” can facilitate good cross-checks.
6.3.2.6.2 Cross-checks should include comparing the expanded coordinates of the waypoints loaded in the FMS to the filed flight plan, track message (if applicable), and the master document.
6.3.2.6.3 You can use various additional techniques in order to verify that the correct points are loaded for your planned route. Verify the total route distance in your FMS against your master document to help find embedded mistakes.
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You should also cross-check course/headings and distances between each waypoint to ensure the FMS routing matches your master document.
Referencing your plotting or orientation chart here can also be beneficial.
Note: A 1° course deviation causes the aircraft to be off planned routing by approximately 1 mile every 60 miles of travel. A course deviation on an oceanic crossing closer to the equator, where leg lengths are typically longer, can result in cumulatively larger displacements from course. However, although leg lengths are typically shorter at higher latitudes, and similar deviations result in cumulatively smaller displacements from course, the density of traffic and closer spacing of parallel tracks at high northern latitudes actually constitute an environment less tolerant of course deviations.
6.3.2.6.4 The second pilot should work from the FMS back to the master document.
Reading from the master document to the FMS can result in “seeing what we expect to see” (expectation bias). A simple way to consider this is that pilot one works from “paper to glass” while pilot two works from “glass to paper.”
6.3.2.7 Adopt an appropriate symbology to indicate the status of each waypoint listed on the master document. For example:
1. The first pilot could circle the waypoint, waypoint number, or symbol on the master document to signify that they have independently cross-checked the entry of the coordinates in the navigation computer.
2. The second pilot could then tick or diagonally slash the circled waypoint, waypoint number, or symbol to signify having performed the cross-check described in paragraph 6.3.2.6 above, to include confirming the course and distance information within a specified tolerance (e.g., plus or minus 2° and 2 NM).
6.3.2.7.1 We will discuss additional master document symbology in the en route section later in this chapter, in paragraph 6.4.
6.3.2.8 Set the appropriate Mode S flight identification (FLT ID).
6.3.2.8.1 ATC systems worldwide are becoming more reliant upon information transmitted by Mode S transponders to manage air traffic. ATC systems use transmitted FLT IDs to uniquely identify each aircraft within a given airspace and correlate them to a filed flight plan for the provision of surveillance and separation services.
6.3.2.8.2 A FLT ID is comprised of a maximum of seven alphanumeric characters
(e.g., N235RA, AAL3342, BONGO33) and corresponds to the Aircraft Identification (ACID) entered in block 7 of the international flight plan.
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6.3.2.8.3 You typically enter your FLT ID through either an FMS interface or your transponder control panel. For ATC systems to function correctly, you must ensure the FLT ID you enter in the FMS exactly matches the ACID in block 7 of your international flight plan.
6.3.2.9 Check your ground speed in the blocks and on taxi out.
1. If you are still in the blocks and your ground speed reads other than zero (0), you may have a developing error in your LRNS.
2. Similarly, if your groundspeed on taxi out appears unreasonable, this may also indicate a problem with your LRNS.
6.3.2.10 Accomplish required Reduced Vertical Separation Minimum (RVSM) altimetry ground checks.
6.3.2.10.1 Before taxi, set your altimeters to the airport local altimeter setting. Both primary altimeters must read within ± 75 feet of field elevation.
6.3.2.10.2 The two primary altimeters must also agree with each other within the limits noted in the aircraft operating manual.
6.4 En Route Guidance.
6.4.1 Oceanic Clearance: How to Request, Receive, and Process.
6.4.1.1 Oceanic clearances are unique clearances that frequently require coordination between two or more air traffic agencies. The clearance you receive from an ATC facility on the ground before departure may not constitute a clearance into or through your filed oceanic and remote continental airspace. Depending on the first oceanic FIR you enter, you may need to obtain this clearance separately and specifically as you approach the oceanic and remote continental airspace boundary. Check the Aeronautical Information Publication (AIP) or source document to determine if such separate oceanic clearance is required.
6.4.1.2 In cases when your departure airport is close to the oceanic and remote continental airspace boundary you may, and at some airports must, obtain your oceanic clearance prior to departure. Check the AIP or source documents to determine clearance requirements unique to your departure airport.
Note: Some airspace authorities have begun issuing the route portion of the oceanic clearance before the aircraft departs, even when the departure airport is not close to the oceanic boundary. In this case, the altitude and airspeed portion will be assigned prior to entering oceanic airspace. New York Oceanic and Oakland Oceanic both operate in this manner.
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