FANS, ADS-B, etc. What you Need to Know

By Jeremy R.C. Cox


The Acronyms

FANS – Future Air Navigation (Required now NATS, and Pacific) FANS is an Oceanic airspace issue at the moment, but will eventually be incorporated over the land as well.

CPDLC – Controller Pilot Data Link Communications (Required in 2015 for new aircraft, and 2017 for all other aircraft, in Europe)

ADS-B – Automatic Dependent Surveillance Broadcast (Required in 2015 for new aircraft, and 2017 for all other aircraft, in Europe. Required in 2020 in USA)

NextGen System – FAA mandated cost saving and efficiency improvement protocol

LINK 2000+ – is the European version of NextGen

WAAS – Wide Area Augmentation System (GPS signal improvement ground stations which improve GPS signal accuracy by 500%)

LAAS – Local Area Augmentation System (an all-weather Instrument Landing signal system that is the same as WAAS, but is specifically built for a runway approach)

LPV – Localizer Performance with Vertical Guidance (High precision WAAS/LAAS enabled Instrument approach and departure guidance procedure)

RNAV – Area Navigation (integrates a variety of navigational aids (beacons, radials, lat/long, etc. to project a virtual flight-path to follow in-flight)

– Required Navigational Performance (Improve RNAV system that has system monitors to tighten-up the accuracy of the virtual flight-path)

MNPS – Minimum Navigational Performance Specification (specific accuracy capabilities are required by air traffic control, in specified control regions and designated air space)

RVSM – Reduced Vertical Separation Minimum

ACARS – Aircraft Communications Addressing And Reporting System (original HF and VHF data communications system that is now being phased out by SATCOM systems)


All of the Systems listed above are in operational use now – today.


Essentially, FANS, ADS-B, NextGen, LINK 2000+, RNP, WAAS, LAAS, LPV are all being implemented to achieve five things:

  1. Improve Air Traffic Control Communications, eliminating the ‘walk-over’ problem with modulating voice transmissions, increasing clarity, reducing both mistakes and human workload
  2. Decrease in-flight separation between aircraft, thus allowing more traffic to use the same patch of airspace
  3. Allow highly accurate, safe and efficient flight-paths to be flown (increasing safety, saving fuel and reducing noise pollution)
  4. Increase safety by having improved awareness of traffic, terrain, weather and NOTAMS, as well as better navigational accuracy
  5. Reduce the operating cost of maintaining an antiquated ground-based navigation and tracking infrastructure system


ACARS communications are facilitated through VHF and HF. It is being replaced by SATCOM. CPDLC communications are now being facilitated by SATCOM through the UHF and Microwave frequencies. Both ACARS and CPDLC are communications systems necessary to meet FANS airspace requirements. The Audio Panel, FMS and Cockpit Voice Recorder (CVR) shall all have to be upgraded, as well as the existing SATCOM and/or ACARS VHF/HF communications systems, to have full CPDLC capability. A text-message printer may also be installed in the cockpit to keep Clearance Deliveries in hard-copy format for future reference (especially if a loss of power situation arises.) The CVR must record all text-messaging as well as cockpit audio.

In non-FANS equipped aircraft separation, errors in navigation and potential errors in voice communication between the flight crew and air traffic control are considered when integrating airspace separation between aircraft. These error factors result in air traffic controllers typically separating each aircraft – typically 100 nm laterally and 120 nm longitudinally. This computes to 48,000 square miles of airspace, causing non-FANS aircraft to operate at less-than-optimum altitudes and speeds. FANS brings this separation down to and between 4 nm and 10 nm.


ADS-B is the integral part of the FAA’s NextGen Program. It is an aircraft and satellite-based transmission system. ADS-B communications are facilitated through VHF (1090 MHz) via the aircraft Transponder System. ADS-B Out has been mandated by the FAA in the airspace that now requires Mode-C Transponder. ADS-B In is the ability of an aircraft to receive information from other transmitting aircraft and the ATC ground infrastructure. Out-Data includes Identification, Speed, Altitude, Rate and Position. ‘In’ data is displayed either on an MFD or an FMS. This In-Data includes Traffic depiction, Terrain depiction, Weather depiction, Airport layout depiction, and NOTAMS.

Unfortunately a costs saving for the various governments around the World, will not readily translate into cost savings for aircraft owners, because the equipment that must be installed into your aircraft, might in some cases exceed the value of your aircraft to begin with.

The aircraft that will cost the most to outfit with new navigation and communications systems will be any aircraft built before 2005. Worst if they are long-range/transoceanic capable aircraft. This is because the onboard GPS/NAV systems, Flight Management Systems (FMS), Transponders, Multi-Function Display (MFD), SATCOM, and Cockpit Voice Recorders will all have to be upgraded.

Example upgrade/compliance costs:

A Gulfstream IV will cost about $1M to comply. A Falcon 900 will cost anywhere from $1.1M to $3.5M. A Challenger 601 will cost >$1.5M. Add to this the cost of in-flight SATCOM data that will always be turned on, when operating within FANS and CDPLC airspace.

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