The FANS Advantage

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Digital data link communications is part of airspace modernization efforts around the world. Compliance with mandates may affect you, as an operator. Learn more about how it works and how it could affect your operations here with Universal Avionics' FANS Technology Resource Guide. Explore the history behind the technology, take note of the various worldwide initatives and mandates, educate yourself and be prepared for the future of digital data link as it becomes more prominent over traditional communication channels like HF.

What is the Future Air Navigation System (FANS)?

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The Future Air Navigation System (FANS) provides direct data link communication between the pilot and the Air Traffic Controller (ATC). Radio or satellite technology (SatCom) is used to enable digital transmission of short, relatively simple messages between the aircraft and ground stations. Communications typically include: air traffic control clearances, pilot requests, and position reporting.

The goal of FANS is to improve performance related to Communication, Navigation and Surveillance (CNS)/ Air Traffic Management (ATM) activities within the operating environment.

The Development of FANS

As far back as 1983, industry officials concerned about the rise in air traffic sought to address an aging infrastructure unable to effectively handle increasing congestion. Responding to the issue, the International Civil Aviation Organization (ICAO) Council established the Special Committee on Future Air Navigation Systems (FANS), which was tasked with identifying new technologies for the future development of navigation systems that would aid in the management of air traffic.

The FANS report was published in 1988, laying the basis for the industry’s future strategy for the CNS/ATM concept; Air Traffic Management (ATM) through digital communication, navigation and surveillance (CNS). Work then started on the development of the technical standards needed to realize the FANS concept.

The Boeing Company, reportedly seeking the cost saving benefit that FANS technology provides, announced the first implementation of FANS in the early 1990s, known as FANS-1. It used existing satellite-based Aircraft Communications Addressing and Reporting System (ACARS) communications, targeting operations in the South Pacific Oceanic region. The deployment of FANS-1 was to improve route choice available to operators, and thereby reduce fuel burn.

Later on, a similar product was developed by Airbus, a Boeing competitor. Today, the two technologies are collectively known as FANS-1/A. Air Traffic Control (ATC) services are now provided to FANS-1/A equipped aircraft in other Oceanic airspaces, and is widely used in the North Atlantic Track System. Efforts to promote the development of FANS-enabled avionics, establish equipage mandates and further develop the CNS/ATM concepts has been ongoing by ICAO. More recently, the FAA and other certifying authorities have sought to utilize FANS-1/A technologies in continental airspace in order to relieve congestion and improve safety.

How FANS Works

The data link system is made up of a number of components that consist of hardware, software and service providers. Air Traffic Service (ATS) providers supply some of the system infrastructure, but the current data link system relies on the networks of Data Link Service Providers (DSP), such as SITA and ARINC, for the delivery of data link messages. Also referred to as Communication Service Providers (CSP), the DSPs are commercial entities that offer similar services, but run their networks in different configurations.

Uplink messages are processed through a FANS router, which then determines the addressee (customer) of the message and delivers the message as appropriate. Messages for different customers are passed between the major CSPs via internetworking agreements.

The Benefits of FANS 1/A+

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FANS represents a potential solution to the growing need for an air navigation system with greater capability.

Aircraft equipped with FANS-enabled avionics experience a reduction in fuel burn and flight time through direct routing. Therefore, costs associated with crew and engine maintenance can also be reduced.

Reduced Separation Between Airplanes

In non-FANS procedural airplane separation, errors in navigation and potential errors in voice communication between the flight crew and air traffic controller are considered when determining the necessary airspace separation between airplanes. Through a satellite data link, airplanes equipped with FANS can transmit Automatic Dependent Surveillance (ADS) reports with actual position and intent information at least every five minutes. The position is based on the highly accurate Global Positioning System (GPS). Digital data communication between the flight crew and the air traffic controller drastically reduces the possibility of error, and allows greatly reduced airplane separations. FANS allows authorities to reduce required separation distances between aircraft, which in turn allows airplanes to fly at their optimum altitude and burn less fuel.

More Efficient Route Changes

Oceanic operations are currently based on weather data that is 12 to 18 hours old. However, by using the satellite data link that is part of FANS, the latest weather data can be transmitted to an airplane while it is enroute. Flight crews can then use this data to develop optimized flight plans, or those plans can be generated on the ground and transmitted to the airplane.

Increased Payload Capability for Takeoff-Weight-Limited Flights

Such dynamic re-routing may allow airlines to consider reducing discretionary fuel, which further reduces fuel burn or allows an increase in payload.

Satellite Communication

Satellite communication can reduce to a few minutes the response time for an airplane requesting a step climb to a new, optimum altitude to reduce fuel burn. Response time is currently 20 to 60 minutes.

No Altitude Loss When Crossing Tracks

To avoid potential conflict, an airplane that is approaching crossing tracks must be separated by altitude from any traffic on another track. As a result, one of the two airplanes can be forced to operate as much as 4,000 feet below optimum altitude. However, if the air traffic controller has timely surveillance data, including projected intent, and the airplane is able to control its speed so that is reaches the crossing point at a given time, altitude separation would be required less frequently.

More Direct Routings

In many cases, current air traffic routings are compromised to take advantage of existing navigation aids and radar coverage, resulting in less-than-optimum routings. Taking advantage of space-based navigation and communication allows for more direct/shorter routes.

UniLink STCs Available Today

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Equipment Installation and Approval

Below is a list of the equipment required for installation approval of FANS on your aircraft. Contact our Sales Department to learn about the solutions we offer to upgrade your aircraft.

• Install FANS 1/A equipment under STC or OEM Service Bulletin (AC 20-140b)
• Universal Avionics TSO-146C FMS - any SBAS-FMS with software version SCN 1000.6 or later
• Communications Management Unit (CMU) UniLink UL-800 or UL-801
• External annunciator ("cube") or installation integrated with Universal Avionics EFI-890R display system
• Aural Alert
• Data-recording CVR, as required by AX 20-160 such as Universal's CVFDR
• Level “D” Satcom system


• For “N” registered aircraft, Letter of Authorization (LOA) for operational approval from the FAA

FANS Regulations

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FANS Technologies

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Controller Pilot Data Link Communications (CPDLC)

A method by which Air Traffic Controllers can communicate with pilots over a data link system, increasing the effective capacity of the communications channel. Data link permits the exchange of text-based messages between Air Traffic Control (ATC) ground systems and the aircraft. It is intended to supplement traditional voice over VHF and HF radio frequencies and free up voice radio channels.

The ICAO standard for Controller-Pilot Data Link Communications (CPDLC) using the Aeronautical Telecommunications Network (ATN) is preferred for continental airspace and is currently being deployed in the core European Airspace. Mandatory carriage of the ICAO compliant system is not the subject of an Implementing Rule, for aircraft flying above FL280, issued by the European Commission. This rule accommodates the use of FANS-1/A by long haul aircraft. All other airspace users must be ICAO compliant.

UniLink™ ATC Flight Level Request

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Airline Operational Control Datalink

A method by which Air Traffic Controllers can communicate with pilots over a data link system, increasing the effective capacity of the communications channel. Data link permits the exchange of text-based messages between Air Traffic Control (ATC) ground systems and the aircraft. It is intended to supplement traditional voice over VHF and HF radio frequencies and free up voice radio channels.

The ICAO standard for Controller-Pilot Data Link Communication (CPDLC) using the Aeronautical Telecommunications Network (ATN) is preferred for continental airspace and is currently being deployed in the core European Airspace. Mandatory carriage of the ICAO compliant system is not the subject of an Implementing Rule, for aircraft flying above FL280, issued by the European Commission. This rule accommodates the use of FANS-1/A by long haul aircraft. All other airspace users must be ICAO compliant.

Automatic Dependent Surveillance-Contract (ADS-C)

Automatic Dependent Surveillance (ADS) reports the current flight position via satellite or VHF data link to the air traffic controller or to the airline. It improves the surveillance of enroute aircraft. ADS-C requires a peer-to-peer relationship with a ground facility to acknowledge receipt of ADS messages.

ATS Facilities Notification

ATS Facilities Notification (AFN) allows the aircraft and the Air Traffic Service (ATS) provider to exchange addresses as well as information about the FANS application supported. AFN can be transmitted via an ARINC 741-compliant SatCom system. Inmarsat and Iridium SatCom have been approved to support FANS oceanic operations, including Safety Services Communications.

Contact Sales

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Need more information about our FANS solutions for your aircraft? Contact Sales