Guidance

Question 1

What are 5 parts to a missile?

Answer 1

Guidance
Warhead
Structure/Body
Propulsion
Control System

Question 2

What are the 3 components of the Guidance section?

Answer 2

Seeker
Flight computer
Autopilot

Question 3

What does the seeker do?

Answer 3

Provides angular error between the target and the missile to the flight computer for correction.

Question 4

What are 3 seeker types?

Answer 4

Infrared (IR)
Radio Frequency (RF)
Electro-Optical (EO)

Question 5

What is the advantage of using two colour seekers in IR seekers?

Answer 5

Difficult to defeat with flairs

Question 6

How do EO seekers work?

Answer 6

Use video scanning, look for a specific pixel pattern

Question 7

What does the flight computer do?

Answer 7

Calculates changes in the missile flight path and turns this into psoitional commands for the control section. Includes autopilot.

Question 8

When does the flight computer use the seeker head?

Answer 8

Terminal phase

Question 9

What are 3 missile guidance strategies?

Answer 9

Command Guidnace
Homing Guidance
Navigation Guidance

Question 10

Command Guidance

Answer 10

“Controlled by an external source that steers the missile to the target” (RF, wire, fiber, etc.)

Question 11

Command Guidance: Beam Rider

Answer 11

The missile stays within the directed beam. NOT the same as CWI illumination.

Question 12

Homing Guidance

Answer 12

Internal equipment enables the missile to steer itself towards a target.

Typically used in terminal phase.

Question 13

What are the 4 types of Homing Guidance?

Answer 13

Active
Semi-Actgive
Retransmission
Passive

Question 14

Homing Guidance: Active Guidance

Answer 14

Missile transmits energy at the target and homes in on the energy reflected back to it. Fire and forget.

Question 15

Homing Guidance: Semi-Active Guidance

Answer 15

An external source transmits energy at the target and the missile homes in on the energy reflected back to it.

Used with short range because illumination must have LOS to target.

Question 16

Homing Guidance: Retransmission Guidance

Answer 16

A combination of semi-active and command guidance.

Semi-active but the missile has no computer to calculate corrections. Missile transmits to the base station which calculates and rebroadcasts information back to the missile.

Advantage is less electronics are required on the missile itself.

Question 17

Homing Guidance: Passive Guidance

Answer 17

The missile detects and homes in on energy that is radiated by the target. Nothing is transmitted at the target.

Difficult to detect and counter.

Eg. IR, EO, Anti-Radiation

Question 18

Navigation Guidance

Answer 18

A method of missile guidance in which the missile steers itself towards a target based on information that is not received from a target tracking system.

Often used for midcourse phase guidance.

Question 19

Autonomous vs semi-autonomous navigation guidance

Answer 19

Autonomous - no external navigation source is used

Semi-Autonomous - Either natural or artificial external navigation source is used

Question 20

What are 4 types of Navigation Guidance?

Answer 20

Inertial
Celestial
Terrestrial
Ranging

Question 21

Navigation Guidance: Inertial Guidance

Answer 21

A form of autonomous guidance in which the missile relies on onboard devices to determine its current position. (accelerometers, gyroscopes.

Question 22

Navigation Guidance: Celestial Guidance

Answer 22

Semi-autonomous

Missile uses angular measurements between celestial bodies and the visible horizon to locate its position and orientation

Primarily used for ICBMs

Question 23

Navigation Guidance: Terrestrial Guidance

Answer 23

Semi-autonomous guidance

Missile uses ground contour matching and altitude or digital video imaging of the terrain to determine its position over land

Primarily used for cruise missiles.

Question 24

Navigation Guidance: Ranging Guidance

Answer 24

Semi-autonomous guidance

Missile depends on external signal transmitters (radio or GPS) to trangulate its position.

Missile recieves time-encoded signals to calculate its own position.

Used on cruise missiles

Question 25

Homing Logic

Answer 25

The trajectory or flight path is determined by the homing logic

Question 26

What are the 2 types of Homing Logic?

Answer 26

Pre-set

Variable

Question 27

Homing Logic: Pre-set

Answer 27

The weapon heading does not vary with target changes in course and speed.

Typically used for stationary targets or slow moving targets over a short distance.

Question 28

Homing Logic: Pre-set: Constant Pre-set

Answer 28

Flies a single path after launch without any variation (like a straight run torpedo)

Question 29

Homing Logic: Pre-set: Programmed Pre-set

Answer 29

Flies a set pattern of programmed paths to reach a target.

Waypoints, or search patern.

Question 30

Homing Logic: Variable

Answer 30

The weapon heading varies with the target changes in course and speed.

Question 31

Homing Logic: Variable: Pursuit

Answer 31

The missile points at the target at all times.

Simple but requires the missile to have speed and maneuverablity advantage.

Question 32

Homing Logic: Variable: Constant Bearing

Answer 32

Missile flies on a straight trajectory towards a predicted intercept point (PIP). A new PIP is calculated as the target moves.

Best for when the weapon speed is comparable to that of the target.

Question 33

Homing Logic: Variable: LOS

Answer 33

The missile is controlled so that it travels along the line of sight from the launcher to the target. (BEAM RIDING)

Question 34

Homing Logic: Variable: Proportional

Answer 34

The missile flight computer measures the rate of change of the LOS to the target (bearing drift) and adjusts the weapon rate of turn by a set coefficient (navigation ratio) to create a more efficient flight path.

The navigation ratio is typically 1:1 or less at the start to conserve velocity and fuel efficiency.

As the missile closes to the target, it can increase to over 10:1 to counter the targets maneuvers.

Question 35

Homing Logic: Variable: 4 types

Answer 35

Pursuit
Constant Bearing
LOS
Proportional