Lesson 1

Center Areas and Splits

Like approach control, En-Route airspace is divided into strategically placed divisions to ensure a balance in controller workload and airspace coverage. En-Route facilities are divided by three components.

1. Area (ZFW Has 6 Different Areas)

2. Sector (ZFW Has 2-3 Sectors Per Area)

3. Altitude (Low, High, and Ultra-High)

Letters of Agreement (LOA)

Being a good neighbor is critical to the success and smooth operation of the national airspace system. LOA's are designed to minimize issues by placing pre-coordinated constraints on aircraft departing, arriving, or transiting the airspace. ARTCC LOA's are published in the controller documents section of the ARTCC website. It is important to become familiar with these when working En-Route, just like SOP's when working a local or terminal position.

Separation Requirements

5−5−4. MINIMA 

d. ERAM: 

1. Below FL 600- 5 miles. 

2. At or above FL 600- 10 miles. 

3. Up to and including FL 230 where all the following conditions are met – 3 miles: 

(a) Within the 3 NM separation area.

(d) The 3 NM separation area is displayable on the video map.

(e) Involved aircraft are displayed using the 3 NM target symbol. 

4. When transitioning from terminal to en route control, 3 miles increasing to 5 miles or greater, provided: 

(a) The aircraft are on diverging routes/ courses, or 

(b) The leading aircraft is and will remain faster than the following aircraft

(c) Separation is constantly increasing and the first center controller will establish 5 NM or other appropriate form of separation prior to the aircraft departing the first center sector

5−5−10. ADJACENT AIRSPACE 

a. Separate radar-controlled aircraft from the boundary of adjacent airspace in which radar separation is also being used by the following minima:

1. When less than 40 miles from the antenna− 1 1/2 miles. 

2. When 40 miles or more from the antenna− 2 1/2 miles. 

7−1−1. CLASS A AIRSPACE RESTRICTIONS 

Do not apply visual separation or issue VFR or “VFR-on-top” clearances in Class A airspace. 

4−5−1. VERTICAL SEPARATION MINIMA 

Separate instrument flight rules (IFR) aircraft using the following minima between altitudes: 

a. Up to and including FL 410− 1,000 feet. 

b. Apply 2,000 feet at or above FL 290 between non−RVSM aircraft and all other aircraft at or above FL 290. 

c. Above FL 410− 2,000 feet, except: 

2. Above FL 600 between military aircraft− 5,000 feet. 

Altimeter Issuance 

2−7−2. ALTIMETER SETTING ISSUANCE BELOW LOWEST USABLE FL 

a. TERMINAL. Identify the source of an altimeter setting when issued for a location other than the aircraft’s departure or destination airport. 

b. EN ROUTE. Identify the source of all altimeter settings when issued. 

PHRASEOLOGY− 

(If the altimeter is one hour old or less), THE (facility name) ALTIMETER (setting). 

or 

(If the altimeter is more than one hour old), THE (facility name) ALTIMETER (setting) MORE THAN ONE HOUR OLD. 

c. Issue the altimeter setting: 

1. To en route aircraft at least one time while operating in your area of jurisdiction. Issue the setting for the nearest reporting station along the aircraft’s route of flight 

4. EN ROUTE. For the destination airport to arriving aircraft, approximately 50 miles from the destination, if an approach control facility does not serve the airport.

e. When issuing clearance to descend below the lowest usable flight level, advise the pilot of the altimeter setting of the weather reporting station nearest the point the aircraft will descend below that flight level. Local directives may delegate this responsibility to an alternate sector when Optimized Profile Descents (OPD) commence in sectors consisting entirely of Class A airspace. 

ERAM's Altimeter List

ERAM will underline report times that are more than one hour old and altimeter settings less than 29.92. This is important because you are required to say "More than one hour old" when giving the altimeter after the report is old. Altimeter settings less then standard indicate that FL180 is unusable.

Speed Restrictions on Arrivals

5-7-2 METHODS

e. When issuing speed adjustments to aircraft cleared on procedures with published speed restrictions specify the point at which the issued restriction begins, ends, or changes the published restrictions. 

PHRASEOLOGY− 

CROSS (fix/waypoint) AT (speed). 

MAINTAIN (speed) UNTIL (fix/waypoint), THEN (additional instructions). 

RESUME PUBLISHED SPEED. 

COMPLY WITH SPEED RESTRICTIONS. 

EXCEPT (if required).

DELETE SPEED RESTRICTIONS. 

CLIMB/DESCEND VIA (SID/STAR name and number) (transition if required.) 

NOTE− 1. Aircraft will meet all published speed restrictions when on any route or procedure with published speed restrictions regardless of climb via or descend via clearance. 

    2. Due to variations of aircraft types, Flight Management Systems, and environmental conditions, ATC should anticipate that aircraft will begin speed adjustments at varying locations along cleared routes or procedures that contain published speed restrictions. 

    3. Issuing speed adjustments to aircraft flying procedures with published speed restrictions may impact the pilot’s ability to fly the intended flight profile of the procedure. 

EXAMPLE− 1. “Cross Alisa at two two zero knots, then climb via the TIMMY One departure.” NOTE− The aircraft will maintain the ATC assigned speed until Alisa waypoint and will then comply with the speed restrictions on the TIMMY One departure .

EXAMPLE− 2. “Cross Alisa at one zero thousand, then climb via the TIMMY One departure, except maintain two two zero knots.” NOTE− The aircraft will maintain the ATC assigned speed of two two zero knots and will not meet any published speed restrictions. Aircraft will meet all published altitude restrictions after Alisa. 

EXAMPLE− 3. “Maintain two two zero knots until BALTR then resume published speed.” NOTE− The ATC assigned speed assignment of two two zero knots would apply until BALTR. The aircraft would then comply with the published speed restrictions. 

EXAMPLE− 4. “Descend via the KEPEC Two arrival, except after NIPZO maintain one eight zero knots.” NOTE− The aircraft will comply with all published restrictions. After NIPZO, the aircraft will continue to comply with altitude restrictions, but will comply with the ATC assigned speed adjustment. 

Self-Assessment

End of Lesson 1