AIM

4/3/14

4−5−6

Surveillance Systems

EXAMPLE

−

Target symbols:

1. Uncorrelated primary radar target 

[

d] [+]

2. Correlated primary radar target

 [

] 

:See note below.

3. Uncorrelated beacon target

 [ / ]

4. Correlated beacon target 

[ \ ]

5. Identing beacon target

 [

5]

:Note: in Number 2 correlated means the association of
radar data with the computer projected track of an
identified aircraft.

Position symbols:

6. Free track (no flight plan tracking)

 [

n]

7. Flat track (flight plan tracking) 

[

à]

8. Coast (beacon target lost)

 [#]

9. Present position hold 

[ 

  ]

Data block information:

10. Aircraft ident 
:See note below.

11. Assigned altitude FL 280, Mode C altitude same or

within 

 200’ of assigned altitude. 

:See note below.

12. Computer ID #191, handoff is to sector 33
      (0

−33 would mean handoff accepted) 

:See note below.

13. Assigned altitude 17,000’, aircraft is climbing,
Mode C readout was 14,300 when last beacon interroga-
tion was received.

14. Leader line connecting target symbol and data block

15. Track velocity and direction vector line (projected
ahead of target)

16. Assigned altitude 7,000, aircraft is descending, last
Mode C readout (or last reported altitude) was 100’ above
FL 230

17. Transponder code shows in full data block only when
different than assigned code

18. Aircraft is 300’ above assigned altitude

19. Reported altitude (no Mode C readout) same as
assigned. (An “n” would indicate no reported altitude.)

20. Transponder set on emergency Code 7700 (EMRG
flashes to attract attention)

21. Transponder Code 1200 (VFR) with no Mode C

22. Code 1200 (VFR) with Mode C and last altitude
readout

23. Transponder set on radio failure Code 7600 (RDOF
flashes)

24. Computer ID #228, CST indicates target is in coast
status

25. Assigned altitude FL 290, transponder code (these two
items constitute a “limited data block”)

:Note: numbers 10, 11, and 12 constitute a “full data
block”

Other symbols: 

26. Navigational aid

27. Airway or jet route

28. Outline of weather returns based on primary radar.
“H” represents areas of high density precipitation which
might be thunderstorms. Radial lines indicated lower
density precipitation.

29. Obstruction

30. Airports

            

Major:
Small: