North Atlantic Radio System Communication Essentials

The North Atlantic Radio System is a critical component of maritime communication, enabling ships and coastal stations to stay in touch across the vast ocean. It's a complex system, but understanding the basics can make a big difference.

The system operates on a range of frequencies, from 2 to 27 MHz, with the most commonly used being the 2182 kHz distress frequency. This frequency is reserved for emergency situations, such as Mayday calls.

Effective communication is key to safe navigation, and the North Atlantic Radio System is designed to provide clear and reliable transmission. Ships and coastal stations use a variety of equipment, including VHF and HF radios, to stay in touch.

The system also relies on a network of coastal stations and ships to relay messages and maintain communication channels. This network is essential for keeping ships informed of weather, traffic, and other critical information.

Check this out: Far North Fiber

In the North Atlantic, voice communication can be a challenge due to the earth's curvature, making VHF waves unreliable in some areas.

To overcome this, HF communication is used, which includes ground waves and sky waves that bounce back from the ionosphere.

Routine air-ground voice communications in the NAT region are conducted via aeronautical radio stations staffed by radio operators who relay messages between aircraft and oceanic ACCs.

There are six radio stations in the NAT: Bodø Radio (Norway), Gander Radio (Canada), Iceland Radio (Iceland), New York Radio (USA), Santa Maria Radio (Portugal), and Shanwick Radio (Ireland).

Radio operators maintain a continuous watch on more than one frequency, so it's helpful for flight crews to state the frequency used when making their initial call.

If this caught your attention, see: B and O Telephone

Voice communication is a crucial aspect of navigation in the NAT region. Electromagnetic waves in the VHF band propagate in a straight line, but due to the earth's curvature, it's often not possible to use it for communication in some parts of the oceanic airspace.

Alternative solutions are employed, such as HF communication, which uses ground waves that follow the earth's curvature, or sky waves that bounce back when reaching the ionosphere. Satellite communication is also used.

You might enjoy: Why Are Radio Waves Important

In the NAT region, operations outside VHF coverage require the carriage of two long-range communication systems, one of which must be HF. The second system can be SATVOICE or CPDLC, provided the coverage criteria are met.

Routine air-ground voice communications are conducted via aeronautical radio stations staffed by radio operators who are not air traffic controllers. These operators relay messages between the aircraft and the relevant oceanic ACC.

There are six radio stations in the NAT region: Bodø Radio (Norway), Gander Radio (Canada), Iceland Radio (Iceland), New York Radio (USA), Santa Maria Radio (Portugal), and Shanwick Radio (Ireland). Radio stations also operate General Purpose VHF (GP/VHF) outlets.

Radio operators usually maintain a continuous watch on more than one frequency, so it's useful for flight crews to state the frequency used when placing their initial call.

Reykjavik centre operates a number of VHF stations in Iceland, Faroe Islands, and Greenland, providing tactical procedural control and ATS Surveillance services. The callsign used is "Reykjavik Control" (or just "Reykjavik"), indicating direct communication with an air traffic controller.

You might like: Radio Resource Control

The inter-pilot frequency 123.450 MHz is used for pilot-to-pilot exchanges of operationally significant information when aircraft are out of range of VHF ground stations.

It's essential to note that this frequency is not for casual conversations, but rather for coordinating critical information.

Aircraft can use 123.450 MHz to relay position reports via another aircraft in case of air-ground communication failure.

This frequency is also used by flight crews to coordinate offsets required in the Strategic Lateral Offset Procedures (SLOP).

The emergency frequency 121.5 MHz should be continuously monitored by all aircraft to be prepared to offer assistance in emergency situations.

Initial contact for relays or offset coordination can be established on 121.5 MHz, but great care must be exercised to avoid unnecessary use of this frequency.

To minimize unnecessary use of 121.5 MHz, aircraft should also monitor 123.450 MHz when possible.

Expand your knowledge: Radio Frequency over Glass