Section 5. Radar Separation

5-5-1. APPLICATION

1. Radar separation must be applied to all RNAV aircraft operating at and below FL450 on Q routes or random RNAV routes, excluding oceanic airspace.

   EXCEPTION. GNSS-equipped aircraft /G, /L, /S, and /V on point‐to‐point routes, or transitioning between two point‐to‐point routes via an impromptu route.

2. Radar separation may be applied between:
   1. Radar identified aircraft.
   2. An aircraft taking off and another radar identified aircraft when the aircraft taking off will be radar‐identified within 1 mile of the runway end.
   3. A radar‐identified aircraft and one not radar‐identified when either is cleared to climb/descend through the altitude of the other provided:
      1. The performance of the radar system is adequate and, as a minimum, primary radar targets or ASR-9/Full Digital Radar Primary Symbol targets are being displayed on the display being used within the airspace within which radar separation is being applied; and
      2. Flight data on the aircraft not radar‐identified indicate it is a type which can be expected to give adequate primary/ASR-9/Full Digital Radar Primary Symbol return in the area where separation is applied; and
      3. The airspace within which radar separation is applied is not less than the following number of miles from the edge of the radar display:
         1. When less than 40 miles from the antenna- 6 miles;
         2. When 40 miles or more from the antenna- 10 miles;
         3. Narrowband radar operations- 10 miles; and
      4. Radar separation is maintained between the radar‐identified aircraft and all observed primary, ASR-9/Full Digital Radar Primary Symbol, and secondary radar targets until nonradar separation is established from the aircraft not radar identified; and
      5. When the aircraft involved are on the same relative heading, the radar‐identified aircraft is vectored a sufficient distance from the route of the aircraft not radar identified to assure the targets are not superimposed prior to issuing the clearance to climb/descend.
   4. A radar-identified aircraft and one not radar-identified that is in transit from oceanic airspace or nonradar offshore airspace into an area of known radar coverage where radar separation is applied as specified in paragraph 8-5-5, Radar Identification Application, until the transiting aircraft is radar-identified or the controller establishes other approved separation in the event of a delay or inability to establish radar identification of the transiting aircraft.

5-5-2. TARGET SEPARATION

Apply radar separation:

1. Between the centers of primary radar targets; however, do not allow a primary target to touch another primary target or a beacon control slash.
2. Between the ends of beacon control slashes.
3. Between the end of a beacon control slash and the center of a primary target.
4. All-digital displays. Between the centers of digital targets; do not allow digital targets to touch.

5-5-3. TARGET RESOLUTION

1. A process to ensure that correlated radar targets or digitized targets do not touch.
2. Mandatory traffic advisories and safety alerts must be issued when this procedure is used.
3. Target resolution must be applied as follows:
   1. Between the edges of two primary targets or the edges of primary digitized targets.
   2. Between the end of the beacon control slash and the edge of a primary target or primary digitized target.
   3. Between the ends of two beacon control slashes.

5-5-4. MINIMA

Separate aircraft by the following minima:

1. TERMINAL. Single Sensor ASR or Digital Terminal Automation System (DTAS):
   1. When less than 40 miles from the antenna- 3 miles.
   2. When 40 miles or more from the antenna- 5 miles.
   3. For single sensor monopulse secondary surveillance radar (MSSR), when less than 60 miles from the antenna- 3 miles.
   4. If TRK appears in the data block, handle in accordance with paragraph 5-3-7, Identification Status, subparagraph b, and take appropriate steps to establish nonradar separation.
2. TERMINAL.FUSION:
   1. Fusion target symbol – 3 miles.
   2. When displaying ISR in the data block- 5 miles.
   3. If TRK appears in the data block, handle in accordance with paragraph 5-3-7, Identification Status, subparagraph b, and take appropriate steps to establish nonradar separation.
   4. The ADS-B Computer Human Interface (CHI) may be implemented by facilities on a sector by sector or facility wide basis when the determination is made that utilization of the ADS-B CHI provides an operational advantage to the controller.
3. STARS Multi-Sensor Mode – 5 miles.
4. 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:
      1. Within the 3 NM separation area, and:
         1. Within 40 NM of the preferred radar; or
         2. Within 60 NM of the preferred radar when using an MSSR; or
         3. When operating in track-based display mode.
      2. The preferred sensor and/or ADS-B is providing reliable targets.
      3. Facility directives specifically define the 3 NM separation area.
      4. The 3 NM separation area is displayable on the video map.
      5. 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:
      1. The aircraft are on diverging routes/courses, and/or
      2. The leading aircraft is and will remain faster than the following aircraft; and
      3. Separation 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; and
      4. The procedure is covered by a letter of agreement between the facilities involved and limited to specified routes and/or sectors/positions.
5. MEARTS Mosaic Mode:
   1. Below FL 600- 5 miles.
   2. At or above FL 600- 10 miles.
   3. For areas meeting all of the following conditions – 3 miles:
      1. Radar site adaptation is set to single sensor mode.
      2. Significant operational advantages can be obtained.
      3. Within 40 NM of the sensor or within 60 NM of the sensor when using an MSSR and within the 3 NM separation area.
      4. Up to and including FL230.
      5. Facility directives specifically define the area where the separation can be applied and definethe requirements for displaying the area on the controller's PVD/MDM.
   4. MEARTS Mosaic Mode Utilizing Single Source Polygon (San Juan CERAP and Honolulu Control Facility only) when meeting all of the following conditions– 3 miles:
      1. Up to and including FL230 within 40 miles from the antenna or within 60 NM when using an MSSR and targets are from the adapted sensor.
      2. The single source polygon must be displayed on the controller's PVD/MDM.
      3. Significant operational advantages can be obtained.
      4. Facility directives specifically define the single source polygon area where the separation can be applied and specify procedures to be used.
      5. Controller must commence a transition to achieve either vertical separation or 5 mile lateral separation in the event that either target is not from the adapted sensor.

         WAKE TURBULENCE APPLICATION

6. EN ROUTE.Provide wake turbulence separation as follows:
   1. Separate aircraft operating directly behind, following an aircraft conducting an instrument approach and/or operating within 2,500 feet and less than 1,000 feet below, by the following:
      1. Behind super - 5 miles, unless the super is operating at or below FL240 and below 250 knots, then:
         1. Heavy - 6 miles.
         2. Large - 7 miles.
         3. Small - 8 miles.
      2. Behind heavy:
         1. Heavy - 4 miles.
         2. Large or small - 5 miles.
   2. Separate a small aircraft behind a B757 – 4 miles when operating directly behind, following a B757 conducting an instrument approach and/or operating within 2,500 feet and less than 500 feet below.
   3. Separate an aircraft landing behind another aircraft on the same runway, or one making a touch‐and‐go, stop‐and‐go, or low approach by ensuring the minima below will exist at the time the preceding aircraft is over the landing threshold. If the landing threshold cannot be determined, the minima should be applied as constant or increasing at the closest point that can be determined prior to the landing threshold.
      1. Small behind large - 4 miles.
      2. Small behind heavy - 6 miles.

         WAKE TURBULENCE APPLICATION

7. TERMINAL.Separate aircraft by the minima specified in TBL 5-5-1 in accordance with the following:
   1. When following an aircraft conducting an instrument approach and/or operating within 2,500 feet and less than 1,000 feet below the flight path of a Category A, B, C, or D aircraft.
   2. When following an aircraft conducting an instrument approach and/or operating within 2,500 feet and/or less than 500 feet below a Category E aircraft.
   3. When departing parallel runways separated by less than 2,500 feet, the 2,500 feet requirement in subparagraph 2 is not required when a Category I aircraft departs the parallel runway behind a Category E aircraft. Issue a wake turbulence cautionary advisory and instructions that will establish lateral separation in accordance with subparagraph 2. Do not issue instructions that will allow the Category I aircraft to pass behind the Category E aircraft.

      TBL 5-5-1
      Wake Turbulence Separation for Directly Behind

      		FOLLOWER
      		A	B	C	D	E	F	G	H	I
      	A		5 NM	6 NM	6 NM	7 NM	7 NM	7 NM	8 NM	8 NM
      	B		3 NM	4 NM	4 NM	5 NM	5 NM	5 NM	5 NM	5 NM
      	C					3.5 NM	3.5 NM	3.5 NM	5 NM	5 NM
      	D		3 NM	4 NM	4 NM	5 NM	5 NM	5 NM	5 NM	5 NM
      	E									4 NM
      	F
      	G
      	H
      	I

8. TERMINAL. ON APPROACH. In addition to subparagraph g, separate an aircraft on approach behind another aircraft to the same runway by ensuring the separation minima in TBL 5-5-2 will exist at the time the preceding aircraft is over the landing threshold.

   TBL 5-5-2
   Wake Turbulence Separation for On Approach

   		FOLLOWER
   		A	B	C	D	E	F	G	H	I
   	A		5 NM	6 NM	6 NM	7 NM	7 NM	7 NM	8 NM	8 NM
   	B		3 NM	4 NM	4 NM	5 NM	5 NM	5 NM	5 NM	6 NM
   	C					3.5 NM	3.5 NM	3.5 NM	5 NM	6 NM
   	D		3 NM	4 NM	4 NM	5 NM	5 NM	5 NM	6 NM	6 NM
   	E									4 NM
   	F									4 NM
   	G
   	H
   	I

9. TERMINAL.When NOWGT is displayed in an aircraft data block, provide 10 miles separation behind the preceding aircraft and 10 miles separation to the succeeding aircraft.
10. TERMINAL. 2.5 nautical miles (NM) separation is authorized between aircraft established on the final approach course within 10 NM of the landing runway when operating in FUSION, or single sensor slant range mode if the aircraft remains within 40 miles of the antenna and:
    1. Wake turbulence separation must be applied in accordance with TBL 5-5-2;
    2. An average runway occupancy time of 50 seconds or less is documented;
    3. CTRDs are operational and used for quick glance references;
    4. Turnoff points are visible from the control tower.

5-5-5. VERTICAL APPLICATION

Aircraft not laterally separated, may be vertically separated by one of the following methods:

1. Assign altitudes to aircraft, provided valid Mode C altitude information is monitored and the applicable separation minima is maintained at all times.
2. Assign an altitude to an aircraft after the aircraft previously at that altitude has been issued a climb/descent clearance and is observed (valid Mode C), or reports leaving the altitude.

5-5-6. EXCEPTIONS

1. Do not use Mode C to effect vertical separation with an aircraft on a cruise clearance, contact approach, or as specified in paragraph 5-14-4, System Requirements, subparagraph f3.
2. Assign an altitude to an aircraft only after the aircraft previously at that altitude is observed at or passing through another altitude separated from the first by the appropriate minima when:
   1. Severe turbulence is reported.
   2. Aircraft are conducting military aerial refueling.
   3. The aircraft previously at that altitude has been issued a climb/descent at pilot's discretion.
3. EN ROUTE. When the position symbol associated with the data block falls more than one history behind the actual aircraft target or there is no target symbol displayed, the Mode C information in the data block must not be used for the purpose of determining separation.

5-5-7. PASSING OR DIVERGING

1. TERMINAL. In accordance with the following criteria, all other approved separation may be discontinued and passing or diverging separation applied when:
   1. Single Site ASR or FUSION Mode
      1. Aircraft are on opposite/reciprocal courses and you have observed that they have passed each other; or aircraft are on same or crossing courses/assigned radar vectors and one aircraft has crossed the projected course of the other, and the angular difference between their courses/assigned radar vectors is at least 15 degrees.
      2. The tracks are monitored to ensure that the primary targets, beacon control slashes, FUSION target symbols, or full digital terminal system primary and/or beacon target symbols will not touch.
   2. Single Site ARSR or FUSION Mode when target refresh is only from an ARSR or when in FUSION Mode - ISR is displayed.
      1. Aircraft are on opposite/reciprocal courses and you have observed that they have passed each other; or aircraft are on same or crossing courses/assigned radar vectors and one aircraft has crossed the projected course of the other, and the angular difference between their courses/assigned radar vectors is at least 45 degrees.
      2. The tracks are monitored to ensure that the primary targets, beacon control slashes, FUSION target symbols, or full digital terminal system primary and/or beacon target symbols will not touch.
   3. Although approved separation may be discontinued, the requirements of paragraph 5-5-4, Minima, subparagraph g must be applied when wake turbulence separation is required.
2. EN ROUTE, TERMINAL (when STARS Multi-Sensor Mode is selected). Vertical separation between aircraft may be discontinued when they are on opposite courses as defined in paragraph 1-2-2, Course Definitions; and
   1. You are in communications with both aircraft involved; and
   2. You tell the pilot of one aircraft about the other aircraft, including position, direction, type; and
   3. One pilot reports having seen the other aircraft and that the aircraft have passed each other; and
   4. You have observed that the radar targets have passed each other; and
   5. You have advised the pilots if either aircraft is classified as a super or heavy aircraft.
   6. Although vertical separation may be discontinued, the requirements of paragraph 5-5-4, Minima, subparagraph g must be applied when wake turbulence separation is required.

5-5-8. ADDITIONAL SEPARATION FOR FORMATION FLIGHTS

Because of the distance allowed between formation aircraft and lead aircraft, additional separation is necessary to ensure the periphery of the formation is adequately separated from other aircraft, adjacent airspace, or obstructions. Provide supplemental separation for formation flights as follows:

1. Separate a standard formation flight by adding 1 mile to the appropriate radar separation minima.
2. Separate two standard formation flights from each other by adding 2 miles to the appropriate separation minima.
3. Separate a nonstandard formation flight by applying the appropriate separation minima to the perimeter of the airspace encompassing the nonstandard formation or from the outermost aircraft of the nonstandard formation whichever applies.
4. If necessary for separation between a nonstandard formation and other aircraft, assign an appropriate beacon code to each aircraft in the formation or to the first and last aircraft in‐trail.

5-5-9. SEPARATION FROM OBSTRUCTIONS

1. TERMINAL. Separate aircraft from prominent obstructions depicted on the radar display by the following minima:
   1. When less than 40 miles from the antenna- 3 miles.
   2. When 40 miles or more from the antenna- 5 miles.
   3. For single sensor MSSR, when less than 60 miles from the antenna – 3 miles.
   4. FUSION:
      1. Fusion target symbol – 3 miles.
      2. When ISR is displayed – 5 miles.
   5. STARS Multi-Sensor Mode – 5 miles.
2. TERMINAL. Vertical separation of aircraft above a prominent obstruction depicted on the radar display and contained within a buffer area may be discontinued after the aircraft has passed the obstruction.
3. EAS. Apply the radar separation minima specified in paragraph 5-5-4, Minima.

5-5-10. ADJACENT AIRSPACE

1. If coordination between the controllers concerned has not been effected, 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.
   3. EAS:
      1. Below Flight Level 600- 2 ¹/₂ miles.
      2. Flight Level 600 and above- 5 miles.
2. Separate radar‐controlled aircraft from the boundary of airspace in which nonradar separation is being used by the following minima:
   1. When less than 40 miles from the antenna- 3 miles.
   2. When 40 miles or more from the antenna- 5 miles.
   3. EAS:
      1. Below Flight Level 600- 5 miles.
      2. Flight Level 600 and above- 10 miles.
3. The provisions of subparagraphs a and b do not apply to VFR aircraft being provided Class B, Class C, or TRSA services. Ensure that the targets of these aircraft do not touch the boundary of adjacent airspace.
4. VFR aircraft approaching Class B, Class C, Class D, or TRSA airspace which is under the control jurisdiction of another air traffic control facility should either be provided with a radar handoff or be advised that radar service is terminated, given their position in relation to the Class B, Class C, Class D, or TRSA airspace, and the ATC frequency, if known, for the airspace to be entered. These actions should be accomplished in sufficient time for the pilot to obtain the required ATC approval prior to entering the airspace involved, or to avoid the airspace.

5-5-11. EDGE OF SCOPE

Separate a radar‐controlled aircraft climbing or descending through the altitude of an aircraft that has been tracked to the edge of the scope/display by the following minima until nonradar separation has been established:

1. When less than 40 miles from the antenna- 3 miles from edge of scope.
2. When 40 miles or more from the antenna- 5 miles from edge of scope.
3. EAS:
   1. Below Flight Level 600- 5 miles.
   2. Flight Level 600 and above- 10 miles.

5-5-12. BEACON TARGET DISPLACEMENT

When using a radar target display with a previously specified beacon target displacement to separate a beacon target from a primary target, adjacent airspace, obstructions, or terrain, add a 1 mile correction factor to the applicable minima. The maximum allowable beacon target displacement which may be specified by the facility air traffic manager is ¹/₂ mile.