Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AmmoTech > 6. Fuzes > Flashcards

6. Fuzes Flashcards

1
Q

Define Fuze?

A

Fuze is a device designed to function an item of ammunition under pre determined circumstances.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Fuzes are classified according to

what three categories?

A 
Filling (ignif or disrupt)

Position

Function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Fuzes classified by FUNCTION have what

three types?

A

TIP

Time, Impact and Proximity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Impact Fuzes are divided into which three

categories?

A

Super Quick(SQ)

Graze

Delay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do the Following acronyms mean?

VT
PIBD
MTSQ
MO
ET
PD
A 
variable time
point intiating base detonating
Mechanical time super quick
multi option
electronic time
point detonating
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

GENERAL REQUIREMENTS

A

SAFETY

RELIABILITuY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the OTHER REQUIREMENTS of a fuze?

A 
Standard weight
Optional delay setting
Multi role to minimise refusing
Must fit standard cavity sizes
Easy time adjustments/setting
Minimum preparation for use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the types of Masking Devices?

A
  • Shutters (Sliding or Rotating)
  • Delay Arming Shutters
  • Delay or Non Delay Masking Shutter (Interrupter or
    Setting Bolt)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the advantages of electronics in

fuzes

A 
Lowers costs due to multi role function

Versatility in arming

Mechanical preparation or initiation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two categories of shutters?

A

Delay or non-delay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Set forward

A

The relative forward movement of components

when a fuze decelerates on impact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

List the Forces Acting on Fuzes (7)

A

Set back
-reaction due to acceleration forces applied on firing
Creep Forward
-When acceleration phase ends, springs compressed re-assert themselves; permits spinning forces
Centrifugal Force
- generated by the lateral velocity imparted by spinning, acting on components outside the CG
Spin Decay
-decay of angular velocity. Can use to trigger self-destruct devices
Set Forward
-Relative forward motion from deceleration on impact
Air or Gas Pressure
-used for turbines; alternate arming method for non spun projectiles
Stored Energy
-Usually a wound spring to operate clockwork devices or shutters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the Four Methods of function for

mines/mechanical fuzes

A 
Pull

Pressure

Pressure release

Tension release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is?

  • Set Back
  • Creep Forward
A

Set Back:
This arises from the reaction of the mechanism to the acceleration forces applied in the gun on firing.
The physical backward movement or anchoring of components compresses springs

Creep Forward:
-When the acceleration phase ends, components which have been locked tend to ease forward on their seatings.
-Springs which have been compressed begin to
re assert themselves.
-This gradual unlocking process permits spin forces to act on components susceptible to them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is?

  • Centrifugal Force
  • Spin Decay
A

Centrifugal Force:
Any component whose centre of gravity is off the axis of the fuze tends to be thrown outwards as a result of centrifugal force generated by the angular velocity
imparted to the projectiles.
Spin Decay:
In the same way that a projectile loses linear velocity, it loses angular velocity.

This decrease in angular velocity can be
used to trigger a self destruction device.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is?

  • Set Forward
  • Air or Gas Pressure
A

Set Forward:
-The relative forward movement of components when a fuze decelerates on impact.
-This can be used to move an inertia pellet
striker onto a detonator.

Air or Gas pressure

  • Sometimes used to drive a turbine to generate power for electrically operated fuzes
  • Used for non spun projectiles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is?

Stored Energy

A

Stored energy is usually a spring
(mechanical) used to operate clockwork
devices or to move shutters.

Chemical energy in an energiser for example,
may be used to generate electrical power or
gas under pressure.

18
Q

What are the 3 types of Time Fuzes?

A

Mechanical
Combustion (Powder Train Time Fuze - PTTF)
Electronic

19
Q

How are time fuzes is designed to function?

A

Time Fuzes are designed to function after a predetermined time whilst in flight

20
Q

There are three types of MT Fuze. What are they?

A

Thiel - British MT Fuzes
A series of wheels and pinions controls the escape of
from a main spring which is wound up during manufacture

Dixi - Swiss Fuze
This mechanism is driven by centrifugal force acting on driving balls

Junghans - American MT Fuzes
This mechanism is actuated by spring assisted by centrifugal weights

21
Q

Position of fuzes vs Impact CATEGORIES. List Each (3) and (3)

A 
Superquick
Graze
Delay
-Point Detonationg
-Base Detonating
-PIBD
22
Q

Impact Fuze - Types./ ACTIONS (4)

xx

A

SNGD

Superquick (SQ)

Non Delay

Graze

Delay
23
Q

Describe Superquick Fuzes (SQ)

A

a needle supported by a thin metal disc or a hammer/striker supported on a shear wire

or coiled spring exposed to a direct blow on impact with the target

24
Q

Non Delay Fuzes

A

These fuzes differ from the SQ fuzes mainly
in being less sensitive

The mechanism usually consists of a steel
hammer / striker supported on a stout shear
pin.

25
Q

Graze Action Fuzes

A

The interior mechanism of graze action fuzes is so arranged that when the projectile is checked in flight or receives an appreciable deceleration

A moveable part, usually called the graze, inertia pellet or plunger moves forward to carry the detonator on to the needle (or vice versa).
A creep spring keeps the two apart until this deceleration is experienced

Graze fuzes have a small inherent delay

26
Q

Delay Fuzes

A

These fuzes usually have a masking shutter, interrupter or pyrotechnic composition in built into the detonating train between the initiator and the fuze magazine so there is a slight delay between the actuation of the initiator and the firing of the magazine.

This may be achieved by channelling the flash from the initiator around a longer route or slowing it by having to wait for the pyrotechnic composition to burn through before it reaches the next component.

27
Q

Position CATEGORIES and description (3)

xx

A

Point Detonating Fuzes (PD)
-Fitted in the nose of projectile and normally shaped to conform to contours of projectile.

Point Initiating Base Detonating Fuzes (PIBD)
-Consist of initiating assembly in nose of projectile and fuze in base.

Base Detonating Fuzes (BD)
-Situated in base of projectile, cylindrical in shape.

28
Q

Define Proximity Fuze

xx

A

Proximity fuzes are automatic time fuzes,

  • with or without PD element,
  • (that are) designed to function a projectile at the optimum lethal distance from the target,
  • provided that in the case of aircraft targets, the trajectory passes sufficiently close.
29
Q

Proximity Fuze Terminology

And what settings are available for MO? (4)

A 
Proximity Fuze: A fuze that reacts to the proximity of the target and detonates the shell.

Variable Time (VT) WW2 term for Proximity

Electric Fuze old US term for Proximity

Multi Option Fuze e.g. M734
–Proximity
–Superquick
–Delay
–Near Surface Burst
30
Q

Difference between VT and CVT?

xx

A

Variable Time (VT) Timer section arms the fuze electronically after firing.

Controlled Variable Time (CVT) Can be set to activate the Prox function after a set time.

31
Q

Explain The Doppler effect

xx

A

Radio waves are emitted by the fuze, some of the waves are reflected and picked up by the receiver

The time taken to return affects the Reflected waves, which interfere with the radiated waves to give a beat
known as the Doppler effect

As the fuze gets closer to the set target distance the impulses increase to a defined peak value and the fuze functions

32
Q

Storage & Handling of Prox Fuzes, need to be Protected from:

A

SHDD

Sunlight
Heat
Dampness
Drop / Strike

  • Stored nose down
33
Q

What are electronic fuzes?

What are the power sources

A 
Electronic fuzes are functioned by a current passing
through electric leads from some sort of battery

Power Sources:
–Battery
–Turbine generated
–Precharged
–Electostatic
34
Q

Design Considerations of Proximity Fuzes (8)

A 
 Rugged
 Economical
 Able to function in all conditions
 Light weight
   Safe to handle
 Not easily jammed
 Able to fit existing projectiles
 Sensitive and rapid in operation
   Have good storage characteristics
 Not subject to false operation

Have good storage characteristics

35
Q

Types of holding, locking and safety devices (8)

A

SSDCSBSH

Shear wire
STRIKER SPRING and spring disc
Detent/setback pin
Centrifugal balls
Stirrup Spring & ferrule. (3-part sleeve)
BORE riding pins. (on outside of fuze)
Safety pins, Cotter and PULL pins
Horse head segments. (2 pivoted segments)

36
Q

Define Firing Device?

A
  • The component which provides the stimuli to initiate the explosive train
  • It may be achieved either mechanically or electrically

*Electrical - Bridge wire, Exploding Bridge wire, Conducting cap

37
Q

What is a common method/example of the 4 Stage for Arming?

A

Unlocking components by SET BACK
Easing it onto its seating on CREEP FORWARD
Swinging it into position via CENTRIFUGAL FORCE
Initiation of the train via SET FORWARD

38
Q

What is a

  • Combustion Fuze?
  • Mechanical Time Fuze?
  • Electronic Fuze?
A

-Combustion fuzes rely on their timing on the burning of a train of pyrotechnic comp.
-Embody a clockwork mechanism which is actuated by setback forces on firing
-Uses the latest microchip tech, can be set from
1-199secs

39
Q

What are the Design Safety features for Fuzes? The system shall be so designed that:

A
  • Cannot be assembled in an unsafe condition

- safety arrangements can be checked during and after assembly

40
Q

What methods / tools can be used to set Time Fuzes?

A

Rotation
Fuze Key
Fuze Setter
Fuzing setting machine

AmmoTech (41 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions