Tools Used for Traffic Flow Management

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There are many instances when ATC needs to move air traffic away from, or into, a particular area of airspace. When this happens, traffic managers will typically implement reroutes – a common route, or set of routes, that they want aircraft to use in a particular area.

Reroutes can be issued as either required, recommended, or "FYI". Required reroutes, as the name implies, are required to be used by all aircraft captured in the scope of the reroute. Recommended reroutes are those which ATC would LIKE operators to use, but are optional. Finally, FYI reroutes are issued by ATC to let operators know that they are available if the operators wish to utilize them.

Current reroute information can be found online by visiting the FAA's Current Reroutes web page or the Advisories Database web page.

A specific application of reroutes is known as the Severe Weather Avoidance Plan (SWAP), which is a formalized program that is developed for areas susceptible to disruption in air traffic flows, caused by thunderstorms. View more information about the Severe Weather Avoidance Plan (SWAP).

Types of Reroutes

Reroutes come in several different varieties:

  • Preferred Routes (sometimes called "pref routes")
  • Playbook Routes
  • Coded Departure Routes (CDRs)

Preferred Routes

Preferred routes are the normal, everyday routes that ATC would like operators to file. These routes were developed to increase system efficiency and capacity by having balanced traffic flows among high-density airports, as well as de-conflicting traffic flows where possible. Preferred routes are those that operators will most commonly file.

Preferred routes can be found online in the FAA's Route Management Tool.

Playbook Routes

Playbook routes are a set of standard routes that ATC can utilize to fit a particular set of circumstances, when the preferred routes are not available. These routes were created to allow for rapid implementation as needed.

Playbook routes are available online in the FAA's National Playbook. Within the Playbook, there are 5 different types of routes:

  • Airport-specfic routes - designed to manage traffic to or from specific airports
  • Airway Closure routes - designed to be used when a primary airway is closed (typically due to severe weather)
  • East to West Transcon routes - designed to manage traffic from the eastern US (primarily the northeast) to the western US
  • Regional Routes - designed to be used for traffic between specific regions of the US
  • West to East Transcon routes - designed to manage traffic from the western US to the eastern US (particularly the northeast)

For more detailed information about Playbook routes and how they are used, visit NBAA's National Playbook page.

Coded Departure Routes (CDRs)

Coded Departure Routes are a combination of coded air traffic routings and refined coordination procedures, designed to reduce the amount of information that needs to be exchanged between ATC and flight crews.

CDRs are typically used at high capacity airports and during inclement weather to make communication between ATC and flight crews more efficient. They are designed for aircraft and crews that have been properly equipped and trained to use them, allowing flight crews and ATC to quickly and clearly communicate entire routes using only eight characters to describe that route.

For example, for a flight between Teterboro, NJ (TEB) and Naples, FL (APF), the route might be: KTEB DIXIE V276 PREPI OWENZ LINND AZEZU L453 PAEPR M201 BAHAA AR21 CRANS LLNCH KAPF. Normally, this route would have to be read by ATC and read back by the crew. The use of a CDR allows this route string to be condensed to "TEBAPFAZ", dramatically reducing the amount of data to be communicated.

Like the preferred routes, CDRs can be located online in the FAA's Route Management Tool.

How to Read Reroutes

Reading reroutes from the National Playbook, an FAA Advisory, or the Route Management Tool is not at all difficult, but can be confusing to those who have not seen them before.

Reroutes are normally divided up into origin segments and destination segments (unless the reroute is a very simple one, issued between only two specific airports) and accompanied by guidance on what flights are affected and when to use the routes.

Reading Reroutes from an Advisory

For example, the screenshot below is a reroute issued in an FAA Advisory, affecting flights between the DC metros airports and NY State and New England.

First, note at the very top of the Advisory the words"ROUTE REQ" – this means that this is a required set of reroutes.

Next, in the middle of the Advisory, there is a chart showing "ORIG" (origin), "DEST" (destination), and ROUTE. So, if a flight is leaving from IAD and flying to BOS, the appropriate route would be "JERES J211 LEONI J109 WEVEL ELZ ITH ALB GDM3"

Please note the remarks located above the chart, indicating when the route is valid, when to use the routes, and what miles-in-trail (MIT) restrictions can be expected.

Reading Reroutes from the National Playbook

Reading reroutes from the National Playbook can be a bit different, but still not difficult. Note the screenshot below - we will use the example of a flight from Fort Lauderdale (FLL) to Teterboro, NJ (TEB).

In this format, the table is broken into two sections and the route is broken into two parts. Our example flight is leaving from FLL, which is contained within Miami Center (ZMA). So, using the "ORIGIN" section of the table, the first part of the route string would be "ORL J53 CRG J55 SAV" (note that the string stops at SAV). Now, jump down to the "DESTINATION" section and pick the route up at SAV – "SAV CAE J51 FAK JAIKE3".