1. What is radar identification?
According to the pilot and controller glossary, radar identification is “the process of ascertaining that an observed radar target is the radar return from a particular aircraft.” In other words, radar identification is confirmation that an observed target is truly the desired aircraft (or an aircraft at all).
2. Identification status
You must inform an aircraft upon initial radar contact.
PHRASEOLOGY-
(ID), RADAR CONTACT (position if required *see below)
You must also inform them when you lose radar contact.
PHRASEOLOGY-
(ID), RADAR CONTACT LOST
“{Reference: FAAO 7110.65 5-3-7}”
Also inform aircraft when you are no longer providing radar services.
PHRASEOLOGY-
(ID), RADAR SERVICE TERMINATED
“{Reference: FAAO 7110.65 5-1-13}”
3. Methods of radar identification
In total, there are six methods for radar identification in the terminal environment (three primary methods and three secondary methods). In order to understand the different methods, we must to distinguish between the two different types of targets. A primary target is a radar target with no additional information, (i.e. a radar return or a “blip”). A secondary target is derived from information sent by a transponder. It is a radar return with other information such as altitude.
A handoff is a transfer of radar contact and radio communications. In the case of an automated handoff (one received via the radar system), there has been no lapse in radar identification, so there is no need to radar identify that aircraft again.
3.1 Primary identification methods
a) Departing aircraft within 1 mile of the runway
You may identify a departing aircraft target within 1 mile of the takeoff runway end at airports with an operating control tower, provided one of these is methods of coordination is accomplished:
1. A verbal rolling/boundary notification is issued for each departure, or
2. A nonverbal rolling/boundary notification is used for each departure aircraft.
Example-
AAL123: “Socal departure, American one twenty-three, climbing through one thousand six hundred. “
You see a target off of 27 within 1 mile.
SAN_APP: “American one twenty-three, Socal departure, radar contact.”
“{Reference: FAAO 7110.65 5-3-2a}”
b) Position correlation
You may radar identify a target whose position (with respect to a fix or visual reporting point) corresponds to a direct position report from that aircraft.
Example-
N123: “Socal approach, Cessna one two three, one zero miles northwest of the Julian VOR, niner thousand five hundred.”
SAN_APP: “Cessna one two three, Socal Approach, radar contact.”
“{Reference: FAAO 7110.65 5-3-2b}”
c) Identifying turns
You may identify a target that you observe making an identifying turn (30 degrees or greater) provided that:
1. A pilot position report is received which assures you that the aircraft is within radar coverage and within your sector.
2. Only one aircraft is observed making these turns.
3. For aircraft operating in accordance with an IFR clearance, you either issue a heading away from an area which will require an increased minimum IFR altitude or have the aircraft climb to the highest minimum altitude in your sector before you issue a heading.
Example-
N123: “Socal approach, Cessna one two three, one zero miles northwest of the Julian VOR, niner thousand five hundred.”
You look at your radar display and you see two targets about 10 miles northwest of JLI, but you are uncertain about which one gave the position report.
SAN_APP: “Cessna 123, Socal Approach approach, turn right 30 degrees for radar identification”
You observe one of them turning while the other remains on its course.
SAN_APP: “Cessna one two three, radar contact, eight miles morthwest of the Julian VOR”
“{Reference: FAAO 711.0.65 5-3-2c}”
3.2 Secondary radar identification methods
a) Observe an aircraft activate the IDENT feature on their transponder.
You may request that an aircraft IDENT, which involves pushing a button on their transponder. If you then observe their data block flash, you can radar identify them.
PHRASEOLOGY-
IDENT
Example-
N123: “Socal approach, Cessna one two three, niner thousand five hundred.”
You have not received a position report and thus may not use it to identify the target, you have to use another method such as asking them to ident.
SAN_APP:“Cessna one two three, Socal approach, ident.”
You observe the data block flash.
SAN_APP: “Cessna one two three, radar contact, one zero miles northwest of the Julian VOR.”
“{Reference: FAAO 7110.65 5-3-3a}”
b) Aircraft changes to a discrete code.
You may identify an aircraft to which you have assigned a discrete code if you observe their data block change.
PHRASEOLOGY-
SQUAWK (code)
Example-
N123: “Socal approach, Cessna one two three, niner thousand five hundred.”
SAN_APP: “Cessna 123, Socal approach, squawk five seven two four.”
You observe the data block change.
SAN_APP: “Cessna one two three, radar contact, one zero miles northwest of the Julian VOR.”
“{Reference: FAAO 7110.65 5-3-3b}”
c) Observe a target lose its information after being asked to squawk standby.
If you request that an aircraft squawk standby, observe its data block lose its information, ask them to squawk normal, and observe its data block regain its information, you may identify it.
PHRASEOLOGY-
SQUAWK STANDBY
followed by
SQUAWK NORMAL
Example-
N123: “Socal approach, Cessna one two three, niner thousand five hundred.”
You have more than one secondary target in your sector but are not sure which one is the Cessna.
SAN_APP: “Cessna one two three, Socal Approach, squawk standby.”
You observe one of the targets lose its information.
SAN_APP: “Cessna one two three, squawk normal.”
You observe the information reappear.
SAN_APP: “Cessna one two three, radar contact, one zero miles northwest of the Julian VOR.”
“{Reference: FAAO 7110.65 5-3-3c}”
4.Position information
You may have noticed that the controller advised the pilot of his position when he identified him. If you radar identify a target by any of the above secondary methods or by identifying turns, you must always state the position of the target in respect to a navaid or airport. There is no need to state position if you are identifying a target by means of a position report or within 1 mile after takeoff.
“{Reference: FAAO 7110.65 5-3-6}”
5. Questionable identification
Use more than one method of identification when proximity of targets, duplication of observed action, or any other circumstances cause doubt during target identification.
“{Reference: FAAO 7110.65 5-3-5}”
6. Validation of Mode-C readout
Whenever you accept an interfacility handoff or start track on an aircraft, you must always verify its altitude. This is because pilots may not be using the correct altimeter setting, and thus they may think they are at an altitude when they really are at another. This can cause problems especially when using vertical separation. An altitude readout is considered valid when it varies by less than 300 feet from the observed altitude. In the real world, pilots nearly always check in with their current altitude. This is not always the case on VATSIM. As a result, you may have to ask them their altitude (if known to be below FL180) or flight level (if known to be above FL180). You may not use vertical separation between tracks with unverified altitudes. If a mode C readout is invalid, give that aircraft the local altimeter setting (if below FL180) or the standard altimeter setting (if above FL180).
PHRASEOLOGY-
(ID), (location) ALTIMETER (altimeter setting), VERIFY ALTITUDE
(ID), CONFIRM USING 2 9 9 2 AS YOUR ALTIMETER SETTING, VERIFY FLIGHT LEVEL
Example-
AAL123: “Las Vegas Approach, American one twenty-three, checking in.”
LAS_APP: “American one twenty-three, Las Vegas approach, say altitude.”
AAL123: “One-three thousand feet.”
If the altitude reported varies by less than 300 feet from the observed altitude, their altitude is verified.
OR
AAL123: “Los Angeles center, American one twenty-three, checking in.”
LAX_CTR: “American one twenty-three, Los Angeles center, say flight level.”
AAL123: “Flight level two five zero.”
If mode C readout is invalid-
LAS_APP: “American one twenty-three, McCarran altimeter two niner niner four, verify altitude.”
OR
LAX_CTR: “American one twenty-three, confirm using two niner niner two as your altimeter setting, verify flight level.”
Mode C can also be verified if you receive a continuous readout from an aircraft on the airport and the readout varies by less than 300 feet from the field elevation. A continuous readout exists only when altitude filter limits are set to include the field elevation.
“{Reference: FAAO 7110.65 5-2-18}”