Fuzing

1
Fuzing

• Naval Weapons Systems

2
Introduction

• Whats the main purpose of a fuze?
• Keep weapon safe when not needed
• Trigger explosive reaction
• Must be reliable and dependable

3
Functions of the Fuze

• Keep weapon safe
• Arm weapon
• Recognize or detect target
• Initiate detonation
• Determine direction of detonation (special fuzes)

4
Basic Fuzing System
Warhead
Target Detecting Device TDD (sensor)
Safing And Arming Device
Warhead
Explosive Output Lead
Detonator
5
Target Detection and Recognition

• Impact or Contact
• Sidewinder, MK-46 torp, Tomahawk, Harpoon
• Ambient - Environmental factor(depth)
• Timer (can be combined with Impact for
  penetration through armor or into hull)
• Command Detonate

6
Target Detection and Recognition (Four Basic
Categories)

• Proximity - Fuzes ability to detect the physical
  presence of the target
• Magnetic, Acoustic, Seismic, Electromagnetic
• SM-2, Sidewinder, Sparrow, Mines, MK-48 torp
• Active, Semi-active or Passive
• Combination of two or more

7
Proximity Fuzes
Active
Semi-Active
Electromagnetic Magnetic Acoustic/Seismic
Passive
8
Fuze Classification(by weapon application)

• Gun Projectile Fuzes
• Rotating Ammo
• Non Rotating Ammo
• Rocket Fuzes
• Bomb Fuzes
• Mine Fuzes (Exploders)

• Missile Fuzes
• Air-to-Air
• Air-to-Surface
• Surface-to-Air
• Surface-to-Surface
• Torpedo Fuzes (Exploders)

9
Safety ArmingReliability

• Safety Arming Sensor
• Barrier between the TDD and the warhead
• Safety - Devices placed in series in firing path
  for safety.
• Reliability - Components placed in parallel in
  firing path for arming firing reliability.

10
Redundancy in Fuze System
S Success F Fail
11
Activation Forces(To arm and/or detonate)

• Setback gt Fuze sets back with great force when
  weapon is launched/fired.
• Centrifugal gt Fuze is thrown to outside of
  casing as bullet spins.
• Creep gt Fuze creeps slowly forward as weapon
  slows due to air friction.
• Impact gt Fuze moves forward with great force
  when weapon impacts target.

12
Homework 10

• Read Chapter 13 Guidance and Control Principles
• Workbook Ch. 14 1,2,3,6,7
• Name the 5 classes based on the manner of fuze
  operation.
• Define Lethal Burst Interval.
• What is the purpose and operation of the safeing
  and arming device?
• List and describe the types of activation forces.