Crossing the Atlantic- A brief guide

Foreword

With increasing cover of the Atlantic FIRs on IVAO, it has become apparent that there is still a lack of understanding on the pilots' side of the procedures and differences in between flying in domestic Airspace and Oceanic Airspace. This guide is set out to simplify the present training material into an easy to understand and translate guide. It shall by no means substitute the present Procedures, but enhance and boil them down to the bare essentials. On conclusion of this guide you, the pilot should be able to:

• A. File a correct flight plan for Oceanic Flights

• B. Obtain the Oceanic Clearance by Voice

• Make Position Reports as appropriate.

Background

With the introduction of jets into commercial passenger operations the Oceans have become very busy with air traffic, which has become an increasing challenge for air traffic controllers to ensure that all aircraft reach their destinations. Owing to the fact that there is still no radar device that is capable of covering the Atlantic Ocean with reliable radar cover. Therefore controllers working on the oceanic sectors need to revert to simple principles of Time, Speed and Altitude in order to keep flights separated.

Apart from using these principles it was also decided that

1. The majority of westbound flights are to be conducted during European Daytime.

2. Equally the majority of eastbound flights are to be conducted during European Nighttime.

And along with these two principal rules it was agreed by the International Civil Aviation Organisation to bundle the North Atlantic Traffic onto several tracks, called the Organised Track System.

North Atlantic Tracks

Each day the Shanwick and Gander Control Centers release a set of 5 to 7 tracks in each direction. Typically they carry the letters A to G for the westbound tracks and U to Z for the eastbound tracks. The precise number of tracks each way varies on a day to day basis and is governed by weektime or weekend and the occurrence of public holidays.

These Tracks consist of two RNAV Entrypoints followed by four or five coordinates of Latitude and Longitude and again of two RNAV exitpoints.

The tracks are being defined and published with due consideration to the Weather situation on the day, especially with consideration to the jet stream winds, which are westerly. The westbound tracks are usually aimed to lay outside the core of the jetstream to eliminate unnecessary headwind, while the eastbound tracks are aimed into the core of the Jetstream to make use of the tailwind.

With the principle of the different times of day for the validity, the extent of the North Atlantic Tracks has been laid out thus:

The validity of the westbound tracks goes from 11:30 Zulu time to 19:00 Zulu.

The validity of the eastbound tracks goes from 01:00 Zulu time to 08:00 Zulu

Both timings refer to the crossing time of 30° Western Longitude, which means that an aircraft that enters the Atlantic at 10:30 Z is well within the validity of the western Tracks, as is an aircraft that leaves the Atlantic at 20:40Z.

If you fly in either direction outside the given times you will be having to fly a random route, more on that later.

The Tracks and their routings are published in the so called Track Message. To check that the Track Message displayed is the up to date, the Track Message is coded with an identifier, also referred to as TMI, which orientates itself on the day of the year. The message issued on 1^st January becomes 001 and so on. This Identifier must be quoted on the oceanic clearance read back if you fly a published North Atlantic Track.

As an example I have picked out two example tracks from the 2^nd of January

You can view the day's tracks and the archive here http://blackswan.ch/nat/

To view my example tracks, type in 002 at the top and press Go, Voila.

I will explain the structure of the tracks using tracks d and u from the day's tracks.

D

MALOT 53/20 53/30 53/40 52/50 CRONO DOTTY

Entry Point Coordinates Exit points

U

YYT NOVEP 48/50 50/40 52/30 53/20 MALOT GISTI

Entry points Coordinates Exitpoints

Along with the coordinates you can see on the pages which flightlevels are available on the respective tracks.

Note that there is also a mandatory onward routing for the westbound tracks and a preceding mandatory routing for eastbound tracks. This is referred to as the North America Route. These are airways connecting the Oceanic Entry/Exit points to RNAV way points just south of the US Border.

The use of a North American Route to and from a track is mandatory.

In our examples these naRs are n162b and n164b for Track d and n55b and n59a for Track u. To find out which of the naRs are the most efficient to use you should consult the Jeppesen table

which Samy has provided here: http://www.ivao.co.uk/training/files/oceanic/NAR.rar

All of these information should help you choose the most appropriate track for your flight to use.

To determine which Track is to be used Ultimately, you should utilise the Great Circle Calculator here:

http ://gc.kls2.com/

Or alternatively you can make use of the Route Generator to determine which is the most

appropriate track to use.

www.simroutes.com

The North Atlantic Tracks are typically the most appropriate Means to cross the atlantic if heading

to or from the following Destinations

North-East Canada

US-Eastcoast as far as Atlanta

Central USA usually as far as Chicago

Occasionally the southernmost Tracks are used eastbounds returning from Central America.

However for most destinations west of Chicago and South of Atlanta the NATs become a considerable detour, for these destinations it is far more appropriate to utilise a random routing. This will be explained at the end of this Tutorial.

Now, on to the Flightplan, which needs to be adapted accordingly to reflect flying through oceanic airspace.

To aid with separation, all flights are adjusted to cancel out the wind effects. This rules out Knots of True Airspeed as flightplanned speed within the oceanic sector. All flights are filed on the premises of Mach speed inside the airspace which is indicated on the entry point by:

M0XX/F3XX, where the X is replaced by the appropriate figures

And on the exit fix by N0XXXF3XX, same goes for X here.

To put it all together, I have illustrated a sample route and flight from London Heathrow using the above Track D. Please note that this route is only an example and due consideration must be taken to use the correct tracks on the day.

The correct and complete route including the Speedchanges:

N0450F320 CPT UL9 STU UN14 BABAN DCT MALOT/M085F350 NATD DOTTY/N0460F380 N162 TOPPS DCT ENE

Also there should be a note of the TMI in the Remark section.

Further on with the tutorial flight

The general setup of the aircraft is similar to normal operations, however there is a difference in the FMC setup for the Oceanic Part.

After MALOT is entered it is time to put in the Coordinates, this is done thus:

In the Boeing Honeywell FMCs (737,747,757,767,777):

Go to the LEGS page

Enter the coordinate in the following format:

53/20 becomes N53W020 53/30 becomes N53W030 and so on

In the Airbus and MD11 FMC the waypoint can either be entered directly on the Discontinuity on the FPLAN page or alternatively on the LAT Rev page of the last waypoint, i.e. MALOT in the following

53/20 becomes 5320N 53/30 becomes 5330N

If Active Sky is used, it is a good idea to generate a .pln File to calculate the enroute winds using http:\\www. simroutes. com

Then the wind information should be entered on the Legs page in the Boeing FMC. Note that the Level D 767 can not yet accept Cruise Winds. It is hoped that this is addressed in the future.

In my Example I am utilising BAW179, which is a 747 service from Heathrow to New York. Airbus and MD11 pilots are kindly requested to substitute the FPLAN for the Legs page.

The Flight- IFR Clearance

The first key difference in our flight is, that the IFR clearance will only be given to the entrypoint. The Oceanic Controller will then issue the onward clearance.

Therefore the IFR clearance phraseology looks thus:

Pilot: Heathrow Delivery, good day, Speedbird 179, Boeing 747, Stand 545 with information Echo, requesting IFR clearance.

ATC: Speedbird 179, Heathrow Delivery, good day, cleared to MALOT via Compton 3G departure, 27 Left, Sqawk 1140

Pilot: Cleared to MALOT via Compton3G departure, 27 Left, Sqawk 1140, Speedbird 179

ATC: Speedbird 179, Readback correct, report fully ready to Ground 121.9

After this, the preflight and departure continue just the same way they would do normally.

The Flight - Oceanic Clearance

After departure it is time to check the ETA at the Entrypoint. You need to call NO LATER THAN 30 Minutes before the entrypoint to get your clearance. If you are inside an area controller's sector, do not worry. The Area Controller will be fully aware of you needing the clearance and will release you.