Figure: Example Plotting Chart (Arrival), from Eddie's notes.

Eddie Sez:

Transforming your craft from an oceanic vessel back to domestic operations is just a matter of making the right contacts, finishing some paperwork, removing SLOP (if any), and getting the cockpit ready for airways, radar contact, and full time air traffic control.

This section continues an example G450 trip from Bedford, Massachusetts (KBED) to Geneva, Switzerland (LSGG), to Mumbai, India (VABB), to Tokyo, Japan (RJAA), to Honolulu, Hawaii (PHNL), to San Francisco, California (KSFO), back to Bedford. For the purpose of covering an oceanic departure, this section will focus on the KBED to LSGG leg. To view the steps required prior to oceanic airspace entry, see: International Operations Manual / Oceanic Departure. For the en route portion, see: International Operations Manual / Oceanic En Route.

What follows comes from the references shown below. Where I think it helpful, I've added my own comments in blue.

Coast-in Navigation Accuracy Check.

Figure: RVSM/Nav Accuracy Log, Coast In, from Eddie's notes.

[AC 91-70A, Appendix 2, ¶2.l.(1)] Compare Ground-Based NAVAID to LRNS. When departing oceanic airspace and acquiring ground-based NAVAIDs, crews should note the accuracy of the LRNS by comparing it to those NAVAIDs. Note any discrepancy in the maintenance log.

The coast-in navigation accuracy check is conducted in the same manner as for coast-out, except that the earliest possible navigation aid is sought for the first opportunity to check navigation performance, keeping in mind the service volume of the navaid is limited. More about this: International Operations / Navigation Accuracy Check.

Strategic Lateral Offset

[AC 91-70A, Appendix 2, ¶2.l.(2)] Remove Strategic Lateral Offset. Crews using a lateral offset of 1 NM or 2 NM right of CL at oceanic entry need a procedure to remove this lateral offset at coast in prior to exiting oceanic airspace. It is advisable to include this as a checklist item.

Domestic Routing

[AC 91-70A, Appendix 2, ¶2.l.(3)] Confirm Routing after Oceanic Exit. Before entering the domestic route structure, crews must confirm their routing to include aircraft speed.

Transition Level.

Figure: Transition Layer Descent, from Eddie's notes.

[AC 91-70A, Appendix 2, ¶2.m.] Descent and Transition Level. During the approach briefing, crews should note the transition level on the approach plate or verified by automated terminal information service (ATIS). Crews must be diligent when descending through the transition level to reset the altimeters to QNH. This is particularly important when encountering instrument flight rules (IFR), night or high terrain situations. Clarify any confusion between a QNH set with inches of Mercury or hPa.

[ICAO Document 4444, Ch 1]

  • Transition altitude: The altitude at or below which the vertical position of an aircraft is controlled by reference to altitudes.

  • Transition Layer: The airspace between the transition altitude and the transition level.

  • Transition Level: The lowest flight level available for use above the transition altitude.

G450 Note: The FMS transition level function will not alert you that you have passed the transition level. Its only function is to determine when FMS altitudes are shown as "FL" on the MCDU.

More about this: International Operations / Transition Altitude/Layer/Level.

Other Coast-in Notes

European Airspace - Chart Etiquette

The most crowded airspace in the world must be in Europe, because the charts are crammed full of airways and fixes. This mess is a carryover from the bad old days when every country had its own border crossing rules and there were border fixes on every border. These days you are very likely to get cleared direct to the opposite border exit point or even further, but you still have to file all those points. If the controller gets busy or is on strike — happens more than you think — you will have to know where those airways are and each of the waypoints too. It really pays to identify all those airways and fixes before your takeoff or coast in:

Photo: European Chart With Highlighter Marks, from Eddie's collection

But what happens on your next trip, and the trip after that. Pretty soon you have too many yellow lines to identify the correct line. There are several techniques out there to fight this:

Photo: European Chart With "Post It" Notes, from Eddie's collection


Figure: RVSM/Nav Performance Log, Final, from Eddie's notes.

[AC 91-70A, Appendix 2, ¶2.n.(1)] Navigation Accuracy Check. When arriving at the destination gate, crews should note any drift or circular error in the LRNS. A GPS primary means system normally should not exceed 0.27 NM for the flight. Some inertial systems may drift as much as 2 NM per hour. Because the present generation of LRNSs is highly accurate, operators should establish a drift tolerance which, if exceeded, would require a write-up in the maintenance log. Required Navigation Performance (RNP) requirements demand close monitoring of drift.

[AC 91-70A, Appendix 2, ¶2.n.(2)] RVSM Write-Ups. Note problems noted in the altimetry system, altitude alert, or altitude hold in the maintenance log. Closely monitor the RVSM airspace for any height deviations. Do not flight plan an aircraft not meeting the strict RVSM standards into RVSM airspace without corrective action.

Record Keeping.

[AC 91-70A, ¶3-6.t.] At the end of each flight, determine the accuracy of the navigational system to facilitate correction of performance. You may perform a check to determine the radial error at the ramp position as soon as the aircraft parks. Radial errors for INSs in excess of 2 NM per hour are generally considered excessive (part 121, appendix G). Keep records on each individual navigation system performance.

[AC 91-70A, ¶3-12.c.]

  1. Record Documentation. Decisions regarding monitoring of an aircraft's navigation performance are largely the prerogative of individual operators. In deciding what records to keep, airlines should consider the stringent requirements associated with special use airspaces such as MNPS. Investigating all errors of 20 NM or greater in MNPS airspace is a requirement for airlines. Whether radar or the flight crew observes these deviations, it is imperative to determine and eliminate the cause of the deviation. Therefore, operators should keep complete flight records so that they can make an analysis. The retention of these documents must include the original and any amended clearances.

  2. Documentation Requirements. Operators should review their documentation to ensure that it provides all the information required to reconstruct the flight. These records also satisfy the ICAO standard of keeping a journal. Specific requirements could include, but do not only apply to, the following:
    • Record of the initial ramp position (latitude/longitude) in the LRNS, original planned flight track, and levels.

    • Record of the LRNS gross error check, RVSM altimeter comparisons, and heading reference cross-checks before entering oceanic airspace.

    • Plotting charts to include post waypoint 10-minute plots.

    • All ATC clearances and revisions.

    • All position reports made to ATC (e.g., voice, data link).

    • The master document used in the actual navigation of the flight, including a record of waypoint sequencing allocated to specific points, ETA, and actual times of arrival (ATA).

    • Comments on any navigation problems relating to the flight, including any discrepancies relating to ATC clearances or information passed to the aircraft following ground radar observations, including weather deviations or wake turbulence areas.

It may be useful to carry an envelope for each planned oceanic leg, labeled with the following information:

The following items, as applicable, should be retained at the aircraft base:

There is no regulatory guidance on how long these records should be retained, other than "within reasonable limits." (AC 91-70A, ¶3-12.b.) We use six months.

Book Notes

Portions of this page can be found in the book International Flight Operations, Part VII, Chapter 4.


Advisory Circular 91-70A, Oceanic and International Operations, 8/12/10, U.S. Department of Transportation

ICAO Annex 10 - Vol V, International Standards and Recommended Practices, Annex 10 to the Convention on International Civil Aviation, Vol V, July 2001

ICAO Doc 4444 - Air Traffic Management, Fourteenth Edition, Procedures for Air Navigation Services, International Civil Aviation Organization, 2001 *

ICAO Doc 4444 - Air Traffic Management, Fifteenth Edition, Procedures for Air Navigation Services, International Civil Aviation Organization, 2007 *

* Not all of Doc 4444 seems to have been reproduced in the 15th edition, so you might need to look at the 15th edition and then then 14th edition for some sections.

ICAO Doc 4444 - Amendment No. 1, Procedures for Air Navigation Services, International Civil Aviation Organization, Amendment No. 1, 2007

ICAO Doc 4444 - Amendment No. 2, Procedures for Air Navigation Services, International Civil Aviation Organization, Amendment No. 2, 19/11/09

ICAO Global Operational Data Link Document (GOLD), International Civil Aviation Organization, Second Edition, 26 April 2013

NAT Doc 001, Guidance and Information Material Concerning Air Navigation in the North Atlantic Region, Seventh Edition, January 2002.

NAT Doc 007, North Atlantic Operations and Airspace Manual Doc 007, Edition 2013