CDC Vol 1, 010 IFF/SIF Fundamentals and Uses

Question 1

• What type of IFF/SIF transponders do we use today?

Answer 1

Mark XII

Question 2

• Which IFF/SIF mode is normally assigned by a command and control authority?

Answer 2

Mode 2

Question 3

• What is the difference between mode 3 and mode A?

Answer 3

Nothing. Mode 3 of the military system is identical in characteristics to mode A of the civil system

Question 4

• What information is provided by mode C?

Answer 4

It provides barometrically-derived altitude data.

Question 5

• How is mode 4 different from the other modes?

Answer 5

With mode 4, the interrogation and response are both encrypted. This enables operators to distinguish between friendly and potentially hostile aircraft.

Question 6

• Which military modes are not used by the civil SSR?

Answer 6

Modes 1, 2, 4, and 5.

Question 7

• List the three mode 3A emergency codes and their meaning?

Answer 7

• 7700 for Emergency
• 7600 for Radio Communication Failure
• 7500 for an aircraft that has hijackers on board or is suffering from unlawful interference.

Question 8

• What does the indentification of postion function provide to aircrews

Answer 8

It enables an aircraft to distinguish its replies from other platforms by causing a distinctive indication on the interrogatior display.

Question 9

• What helps improve tracking continuity when used in conjunction with radar?

Answer 9

IFF/SIF

Question 10

What was the IFF system called that was installed during WWII?

Answer 10

Radar Beacon System

Question 11

What does FAA call their version of IFF/SIF?

Answer 11

Air Traffic Control Radar Beacon System (ATCRBS)

Question 12

What two systems make up the Mark XII

Answer 12

• IFF/SIF

- ATCRBS (Air Traffic Control Radar Beacon System)

Question 13

Who controls the radar beacon systems?

Answer 13

• DoD

- FAA

Question 14

What country developed the first series of transponders and what was it called?

Answer 14

• The British in 1940

- Mark I

Question 15

What series of the transponder was the interrogator added?

Answer 15

Mark III

Question 16

What does IFF systems consist of?

Answer 16

• Interrogators
• Transponders
• Processing equipment
• Related antenna systems

Question 17

What is the primary function of IFF/SIF?

Answer 17

To assist in the rapid and reliable ID of friendly aircraft, ships, and platforms while supporting the tracking and control f friendly aircraft.

Question 18

What modes can be used by the Mark XII?

Answer 18

Modes 1,2,3/A, C, and 4

Question 19

What series of transponders is able to use mode 5?

Answer 19

Mark XIIA

Question 20

What modes are military moves?

Answer 20

Modes 1-5

Question 21

What is IFF called in the civil air traffic control environment?

Answer 21

Secondary Surveillance Radar (SSR)

Question 22

What are the civil modes?

Answer 22

Modes A, C, and S

Question 23

What mode is used to convey the aircraft’s mission?

Answer 23

Mode 1

Question 24

In most Mark XIIs, how many Mode 1 reply codes are available?

Answer 24

32

Question 25

In the Mark XIIA, how many Mode 1 reply codes are available?

Answer 25

4096

Question 26

How many reply codes are available for Mode 2 and Mode 3?

Answer 26

4096

Question 27

What is the function of Mode 2

Answer 27

Personal ID

Question 28

Is Mode 2 variably or aircrew selectable?

Answer 28

Variably

Question 29

Who typically assigns Mode 2s?

Answer 29

C2 Authority

Question 30

What can mode 2 represent for Naval aircraft?

Answer 30

Aircraft’s side number

Question 31

What mode is each aircraft assigned a unique address, though military platforms have the capability to change the address in use when operationally required?

Answer 31

Mode S

Question 32

What is an enhanced feature of the Mode S system which provides automatic self-reporting of a platform’s location?

Answer 32

ADS-B (Automatic Dependent Surveillance-Broadcast)

Question 33

What mode has the capability to send national origin information and a platform ID number in replies and reports?

Answer 33

Mode 5

Question 34

What system does Mode 5 connect to in order to provide an aircraft’s Lat/Long and altitude?

Answer 34

Global Navigation Satellite System

NOTE: Mode 5 has a merit number that represents the accuracy of the position information.

Question 35

With Mode 5, what does Mode 5 level 1 provide and what does level 2 provide?

Answer 35

• Level 1 provides challenge and response

- Level 2 provides reporting functionality

Question 36

What two modes are encrypted?

Answer 36

• Mode 4

- Mode 5

Question 37

When the emergency feature is selected, how does the transponder reply to each interrogation?

Answer 37

With four pulse groups spaced 4.35 microseconds between groups.

Question 38

What function enables an aircraft’s transponder to distinguish its replies from those of other platforms (when requested), by causing a distinctive indication on the interrogator display?

Answer 38

I/P or Ident (IP = Identification of Position)

Question 39

When selected, how long are I/P ( Identification of Position) transmitted for?

Answer 39

Approximately 18 seconds

Question 40

Control for ground and surface transponders are very similar to airborne transponders except for?

Answer 40

EMERGENCY, IDENT (I/P) and Mode C may be omitted.

Question 41

Why might a radar only receive an IFF/SIF signal and not a radar signal?

Answer 41

The IFF/SIF may be much stronger and overpower the radar signal.

Question 42

What can be used in conjunction with radar to help improve tracking continuity?

Answer 42

IFF/SIF