26 - Exterior Ballistics, Propulsion, and Midcourse Guidance

Question 1

Propulsion types

Answer 1

Power reqiured to propel a warhead from Launch to Aim Point
- Gravity
- Reaction
- Impulse
-Ejector-type
-Gun-type

Question 2

Gravity Propulsion

Answer 2

Uses potential energy from Launch to Aim Point

All free fall and glide bombs

Question 3

Reaction Propulsion

Answer 3

On-board energy source creates thrust to Aim Point
- Turbo-Jet
- Rocket engine
- Propellor Driving (torpedoes)

Question 4

Jet Engines - Turbojet

Reaction Propulsion

Answer 4

• “Air Breathing”= atmospheric
• Accelerate air = Action = Reaction = Thrust

Question 5

Missiles

Reaction Propulsion

Answer 5

• May NOT need air (brings oxidizer)
• Solid or Liquid fuel/O</sub>2

Question 6

Torpedo

Reaction Propulsion

Answer 6

• Brings oxidizer
• Propelled by screw

Question 7

Impulse Propulsion

Answer 7

All energy provided via launching impulse mechanism
- Ejector-Type
- Gun-Type

Flight path determined by Muzzle Velocity and Exterior Ballistics

Question 8

What are Exterior Ballistics?

Answer 8

Natural phenomena that impact a weapon in flight
- Gravity
- Drag
- Drift
- Coriolis Effect

Question 9

Exterior Ballistics: Gravity

Answer 9

“Drop”
- Distance the projectile falls from line of fire
- Predictable

Question 10

Exterior Ballistics: Drag

Answer 10

Movement through atmosphere results in opposing forces
- Skin
- Shape
- Wave

Question 11

Exterior Ballistics: Wind

Answer 11

Effects the projectile aim point
- Cross Wind
- Range wind

Question 12

Exterior Ballistics: Drift

Answer 12

Projectile’s arcing path due to a combination of gyroscopic forces and relative wind due to rotation

Due to Projectile rotation

Question 13

Exterior Ballistics: Coriolis Effect

Answer 13

Due to the rotation of the Earth
- Only affects long distance rounds moving longitudinally
- Causes acceleration at right angles to path to motion

Question 14

Purposes of Guidance Systems

Answer 14

1. Attitude control
2. Flight Path Control

Question 15

Phases of Guidance Systems

Answer 15

• Boost (Inertial)
• Midcourse (Guided)
• Terminal (Guided)

Different phases may use different guidance systems

Question 16

Types of Guidance Systems

Answer 16

1. Control Guidance
2. Homing Guidance
3. Track Via Missile (TVM)
4. Self Contained

Question 17

Control Guidance Types

Answer 17

1. Command guidance (RADAR command)
2. Beam rider
3. Wire guided

Question 18

Homing Guidance Types

Answer 18

1. Active
2. Semi-Active
3. Passive

Question 19

What is Homing Logic?

Answer 19

Determines how a Homing Guidance weapon will reach the desired Aim Point
1. Preset logic - (cannot be changed midcourse)
2. Variable homing logic (adjusts during travel)

Question 20

Preset Homing Logic

Answer 20

• Constant
  -Only maintains attitude control, aiming is done prior to launch
• Programmed

Question 21

What is Self Contained Guidance?

Answer 21

Path to Aim Point predetermined prior to weapon launch
- GPS
- Celestial
- Inertial (“Dead Reckoning”)
- Terrestrial

Question 22

Homing Logic types

Answer 22

1. Pursuit
2. Constant Bearing
3. Proportional Navigation