THE INS AND OUTS OF ADS-B

Updated: Dec 1, 2020

ADS-B went into mandatory effect on January 1, 2020.


Here's what you need to know.


WHAT IS ADS-B?

ADS-B stands for Automatic Dependent Surveillance Broadcast and is a primary technology supporting the FAA's Next Generation Air Transportation System. It essentially shifts aircraft separation and air traffic control from ground based radar to satellite derived positions.


WHAT IS THE DIFFERENCE BETWEEN ADS-B OUT AND ADS-B IN?

ADS-B OUT

Works by broadcasting information about an aircraft's GPS location, altitude, ground speed and other data to ground stations and other aircraft, once per second. Air traffic controllers and aircraft equipped with ADS-B IN can immediately receive this information. This offers more precise tracking of aircraft compared to radar technology, which sweeps for position information every 5 to 12 seconds. As of January 1, 2020 ADS-B OUT is MANDATORY for flight operations in the airspace areas listed below.


ADS-B IN

ADS-B IN is OPTIONAL and provides pilots with weather and traffic information delivered directly to the cockpit. Pilots flying with ADS-B IN have access to the graphical weather displays in the cockpit as well as text-based advisories including Notices to Airmen (NOTAMS).


WHERE IS ADS-B OUT REQUIRED?

The airspace rules requiring ADS-B are found in FAR 91.225. It dictates that ADS-B OUT is required in the following airspace areas:

  1. Class A Airspace

  2. Class B Airspace

  3. Class C Airspace

  4. Class E Airspace at or above 10,000' MSL

  5. Within the Mode C Veil of Class B Airspace

  6. Above the Ceilings of Class B and Class C Airspace up to 10,000' MSL

If you wish to fly in any of the airspace areas listed above, you will need to have an operating ADS-B OUT Unit.


CAN I REQUEST AN EXEMPTION?

What if you want to fly in one or more of the airspace areas listed above but your ADS-B is inoperative?


You can request deviation authorization through the FAA's ADAPT tool at the link below. This request must be done online at least one hour before but not more than 24 hours before the intended flight.


ADAPT Request >


WHAT IF MY ADS-B FAILS IN FLIGHT?

If your ADS-B fails in flight, you can continue to your Destination Airport and ATC will coordinate your flight and intended arrival.


Author - Nate Hodell

CFI/CFII/MEI/ATP - Creator of wifiCFI - Owner of Axiom Aviation Flight School.


This information is included in the ADS-B Lessons on wifiCFI. Sign up today to watch videos, listen to podcasts, take lesson quizzes, join live webinars, print lesson quicktakes, and more by clicking this link >


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