Air launched guided weapons 7316 Flashcards
whats the definitions of a guided missile
contains or is connected to equipment which enables the flight path of the missile to be monitored and altered
definitions of a guided weapon
everything required to convey a guided missile from its storage site to a selected target
this includes:
missile
launching equipment
radars and fire control equipment
as well as the equipment for servicing testing and operating tyhe missile
describe the requirements of a guided missile airframe
- strong enough to contain missile components and withstand massive ‘G’ forces during captive and free flight
- hoisting and carriage facilities, and attachment ponts for control surfaces
- light to provide max range without having an overley large propulsion
- aerodynamic for max efficiency
what are the classifications of missiles?
A.A.M: AIR TO AIR MISSILE
S.A.M: SURFACE TO AIR MISSILE
A.S.M: AIR TO SURFACE MISSILE/ ANTISHIP
S.S.M: SURFACE TO SURFACE/SHIP TO SHIP MISSILE
Describe a blast warhead
relies on the blast wave caused ny the detonation to create excessive forces on the target
if combined with tamping can also create fragmentation effect
describe a fragmentation warhead and how is the effectivness of fragmentation determined
metal casing is designed to break-up when detonation occurs, to cause maximum damage from fragmentation travelling at high velocity
this is determined by:
A. increasing the number of fragments
B. decreasing the size of fragments (this causes a decrease momentum and therefore penatration effect)
describe annular fragmentation warhead
wrapped with titanium metal rods the explosive effect acts outwards in a cone or petal shaped pattern, with little blast going backwards/forwards
uses a proximity shaped fuze or impact fuze
describe expanding rings
continuous rods
expanding ring that breaks when it reaches max distance, and carries on as fragments
what is a blast pentatration warhead
heavy casing and stable explosive filling to withstand shock of penetration with a delayed fuze to aid with maximum structural damage
what is a tandem charge warhead
armour piercing shape and delayed action fuze penetrates the target before detonation occurs
dual blast to penetrate armour and detonate inside target
explain shaped charge warhead
munnro effect
instantanious impact fuzing
briefly describe contact fuzing
upon direct contact with target it will either be initaited simultaneously or with a delay to impart maximum damage,
types of contact:
electrical crush fuze
piezo-electric crystal
or inertia strikers
what is proximity fuzing
ususally used in A.A.M. aircraft are quite fragile so they will be effected by detonations that occure close by, (type of warhead) so the missile doesnt need to score a direct hit,
useally uses optical/radio/radar systems to detect targets
what are variable time fuzes?
allows the warhead to function after a pre-set delayed time using mechanical or electrical timers generally used with stationary targets
with reference to fuzes explain self-destruct
this is when the onboard electronics which run a clock to provide a timed self-destruct.
failing power output from internal power can also initiate a self destruct
what safety features are integrated within the safe arming unit (SAU)
- the shutter retains the detonator and pyro out of alignment
- acceleration latch arm prevent movement of the shutter prior to missile release
- withdrawal lanyard locks acceleration sensitive latch arm in position
- the latch arm can re-engage with shutter if accleration isnt maintained
- the igniter firing lines are short-circuited until the piston gas motor is fired
- RF filters prevent ignitition due to spurious RF radiation
state the purpose of the fuzing system
and
stringent requirements for arming
purpose: ensures warhead detonates at the correct time and prevents detonation during normal handling carriage and storage.
must have:
sufficient sustained acceleration,
time
safe separation distance
explain liquid fuel (turbojet)
used in long range missiles where economy is an advantage,
contains mini-jet engine, burning low cost conventional jet fuel
expensive
complex
limited in altitude
solid fuel rockets
burns fuel in atmospheric oxygen
rocket contains fuel and oxygen
can be used in a variety of specialist missiles
high operating speed and no altitude limits
what are the pros and cons between solid and liquid fuel
liquid is slower and limited in altitude,
solid is faster and no altitude restrictions
why is venturi effect used in propulsion nozzles
a narrow ‘thoat’ at the exhaust exit, venturi increase speed of exhaust gasses
how may you improve rocket motor performance
change the construction of the propellant either by shaping the cross sectional area or forming the proppellant into different sized granules or sticks to change the burn area
briefly discuss the construction of the ignition system
- booster motors
large surface area high thrust for short period
- sustainer motors
burning surface lessened and controlled to give a steady burn, low thrust over a long period of time
- composite motors
combination of both booster and sustainer motors
where are the limits of drop distance damages and temperature ranges laid down
SEXSSI/MTP
what can cause rocket motor damage
- cracks/ misshaping:
results in a change of the propellant burn are which could cause an increase to burst pressure in the rocket tube
- incomplete initiation of the propellant
would prevent the missile accelerating at its design rate and therefore may not meet the requierments for arming
what is guidance in missiles used to overcome or at least reduce
- initiial aiming errors
- unpredictable variations in the flight of the missile
- evasive action taken by the target
describe beam riding guidance
illuminated by an EM beam
the missile stays within the beam
explain command guidance
target detected by one radar
missile launched at target tracked by another radar
computer steers missile to intercept point
info transmitted via data link
line of sight:
short range
human aimer
controlled via joystick
describe homing guidance
missiles home in on received signals from target either from outside source or by missile and responds to that signal
with reference to homing explain types of homing
active: missile contains a transmitter/receiver transmits some form of energy towards target and follows received energy (similar to radar)
semi-active: missile receives reflected energy from outside source
passive: has a detector that receives energy from target (radio, sound waves IR or light)
describe proportional navigation
calculates target heading and velocity to calculate collision course,
avoids excessive manoeuvres for a pursuit course
constant bearing gives a better range
state the advantages of an IR guidance missile
accuracy
lethality
simplicity
security
tactical freedom
difficulty of applying countermeasures
what are the functions of the control services
- provides roll and roll rate stabilisation
- to correct any missile instability
- accepts the manoeuvre demands and convert them into the control movements
what is meant by cartesian control
the control surfaces are at a right angle to each other and operate as pairs with guidance demands supplied as “up/down”, “left/right” signals
can move in both planes silultaneously
what is meant by polar control
has only one pair of moving surfaces
can only move in one plane at a time
name and briefly describe the 3 fixed or moving nozzle systems
- jet deflectors/vanes
mechanical vanes are used to deflect motor exhaust to one side
- jet tabs
similar in principle to jet deflectors/vanes but zero thrust lost since the tabs are outside the jet
- jetevators
a ring placed around the circumference of the nozzle moves to deflect the vanes/tabs does not interfere with exhaust flow
what must a missile power supply be capable of doing
- capable of remaining in storage for years, but quick to activate
- checked prior to launching to ensure it will function as intended
- activated without causing either a voltage surge or voltage drop when compared to pre-launch electrical power
describe the workings of a thermal battery
this is a dry battery with a solid gel electrolyte, this becomes a liquid when exposed to extreme heat caused by an explosive squib activating the battery
describe the working of a turbo generator
generators driven directly by the turbine exhaust, or a pre-charged cylinder within the missile
explain how an IR guidance control system works
chopper disc/reticule: pics up IR light
precession coils: move the seaker head towards the IR light source, through EMF, due to the out of phase IR light on the chopper disc
phase detector: detects the phase diference between the IR source from the chopper disc and the direction the missile is actually going
reference coils: detects homing head displacement, (from permanent magnetic) becomes unbalanced, signal compared with the error signal in the phase detector
controls fins: moves missile in desired direction
servo pistons: ensures gas outflow is correct pressure
balance chamber: ensures gas outflow is is same as inflow
describe pyrotechnic igniters
used to initiate liquid and solid fuel propusion systems
ignited by either a spark dishcharge or hot wire
describe a torque balance system
torque balance control system is basically the servo assembly, a method of driving the fins to either one of two positions
name the components of a generic sidewinder missile
Guidance control section
canards
active optical target detector
safe arming device (SAD)
warhead
Rocket motor
wings
rollerons
name and describe the sidewinder variants
operational - used to acquire, track and destroy targets
acquisition - used during aircrew training to acquire and track a target
Telemetry - usedto prove operational missile under test conditions, warhead replaced with an electronics unit to downlink useable data
3 marks
name and describe the 3 main guidance control sections (GCS)
infrared seeker assembly - used for detecting and tracking the target
electronics assembly - used for converting detected target information to tracking and guidance command signals
Servo assembly - converts electrical guidance commands to mechanical movement
what is the Base block
Houses an inertia switch that uses deceleration (contact of the targetof 250G) to activate a switch creating a fireing pulse
two functions of the umbilical cover
prevents and dirt and particles getting into the umbilical coolant gas pipeline
create a short circuit to isolate the firing circuit from the rocket motor
purpose of the umbilical connector
two way data transfer between missile and A/C and pipeline for missile coolant
describe the purpose of the Active optical target detector (AOTD)
detects the presence of a target to maximum effective range,
and generates an electrical firing signal to initate warhead detonation
briefly state the purpose of SAD
- prevents the warhead from functioning during storage, handling and transportation
- designed to arm at a safe distance from launched aircraft (SSD)
- detonates warhead upon command
what is the purpose of the safe-arm key
miss aligns the propulsive train to provide maximum safety by preventing accidental inadvertant rocket igniton
purpose of the rolleron
helps stabilise the missile and provides roll stabilisation
3 main operations of missile launch
the GCS thermal battery operates?
initiates the AOTD thermal squib
applies a fireing voltage to the GCS servo gas grain generator squid
activates the SAD to electro-mechanically allow the arming process to continue
describe missile free flight operation
uses proportional navigation through cartesian control until proximity or impact detonation
warhead arming cannot be achieved unless
and
what happens if one of these conditions isn’t met
- deliberately launched
- sufficient acceleration
- sufficient time has elapsed following live release (SSD)
self destruct signal is sent to SAD
how does the focal plane array work
recognises specific target profiles rather then a heat seeker
uses an array of detector elements (cooled to 77K) that identify energy from the missile’s surroundings to allow it to build a spatial map of the scene
the cryogenic engine ensures there is coolant for the entire mission
breifly describe a cryogenic engine
negates the need for nitrogen cooling via the launcher
ensures there is coolant available for the entire mission
what are the precautions to observe when handling the 9X sidewinder
do not lift or handle missle by jet vanes
ensure sheer wires aren’t removed
what is the arm and fire device?
same as the safe arm key
safe arm selector handle uses a cross design
the safe or armed condition is indicated by the position of the white extension
it miss aligns the propulsive train to prevent inadvertant firing of the rocket
briefly describe a meteor missiles with regards to the data link
has a data link facility that allows the launch aircraft or third parties to provide mid-course target updates or retargeting commands before an active homing radar seeker is employed for the terminal phase
name and briefley describe the 4 variants of paveway P4
operational - this is a live warshot
practice - same flight characterisitcs as operational its cleard for flight, but with inert warhead and fuze
drill - known as the ground crew training weapon, not cleard for flight
telemetry - used to provide firing data
name the 4 main component parts
warhead
enhance computer control group (ECCG)
P4 multi event hard target fuze (MEHTF)
bomb convdrsion kit
describe how the P4 has been improved
to improve penatration survivability the case uses stronger alloy design combined with minimal increase in case thickness
name and describe the 3 major sub assemblies of the (ECCG)
Guidance electronic detector assembly (GEDA)
control actuation section (CAS)
laser seeker
need 3
explain the parts of the GEDA with referencce to ECCG
contains:
selective availability anti-spoofing module (SAASM)
GPS Aided inertial navigation system (GAINS)
two GPS antennas
height of burst (HOB)
keep alive battery port
only need 3
parts in the control actuation section (CAS)
thermal battery
system battery firing device (BFD)
gas bottle/squib
two environmental conditions of P4
detects SSD with a timer and perfroms a ballistic weapon arming manoeuvre (BWAM)
what is late arming conditons
late arming is when the bomb will arm 1 sec before impact a long as it bomb is:
on course
serviceable
not being jammed or spoofed
and can only function when guidance is via GPS or INS
how are boosters and fuzes matched
there must be matched serial number pairs
especially the AFG
what are the P4 acceptance checks
- aerofoil group
AFG securing screws
Tail unit release lever safety pin
Tail unit safety pin
what are the purposes of the Forward adapter assembly and the nose plug
forward adapter assembly - provides mechanical interface between the warhead body and the ECCG
nose plug - used to interface with the forward adaptor and the enhanced penetration performance
safety handling precautions with the P4 AFG
has a fragile construction at rear of each wing quadrant and therefore is not to be placed upright standing on the wing end
precautions for the keep alive battery for the P4
- must be replaced after every weapon sortie or after 24hrs if not flown
- tendency to over heat
what is the safety arrangement for the BFD
the safety wire is to pass through the firing pin, around the BFD twice, and have a safety pennant fitted
what are the personnel safety precautions should you see signs of thermal battery activation
if any discolouration of the P4 ECCG due to heat then do not touch and leave for atleast 4 to 6 hours for cooling
what are the indications the thermal battery is operated
heat sensitive pad colouration
white = servicable
black = unservicable/ operated
ECCG storage container precautions
follow the relevent 5X preparation procedures
- undo the latches at the four corners first, listen for escaping gases, if gases heard leave area let gases vent
- undo the latch adjacent to the operator ensuring there is no obstruction opposite
- under the final latch on opposite side and remove lid
what is selective availability (SA)
deliberate error to deny potential aggressors with the most accurate positional data available
what is anti-spoofing
a facility that is able to decrypt the GPS signal to authenticate their source and validity
4 points
during prep and assembly what is the purpose of the readiness test set
- supply operating voltages to the ECCG
- monitor voltages from the ECCG and indicate pass or fail
- test gas bottle firing pulse
- check the acquisition and guidance circuits of the ECCG using a simulator ‘wand’
what is the purpose of the chamelon laptop
checks power circuit responses and directional signals and checks the GAINS system
what are the general armament safety precautions (GASPS)
missile returned unservicable if dropped more that is laid down in releavent SEXSSI (JSP862)
protective covers and pins are to remain fitted to missiles for as long as possible
do not roll or tumble rocket motor
avoid touching the rocket motor firing contacts
what actions are to be taken in the event of a damaged infrared glass dome
what would you use in the event of a missile fire and for how long
AFFF to extinguished the fire water to cool for 30 mins
this alleviates mechanical expansion stresses
and increased sensitivity of explosive content
why is the defects reports procedure in place
to report all failures and faults within a timescale
ensures the incident is quckly investigated and identified
and helps to ensure corrective actions can be implemented
how is the MF760 defect report to be distributed out
- translucent form with equipment to defence munitions
- one copy to the DM where equipment is to be landed
- one copy to administrative authority so precautionary step can be carried out
- one copy retained by the originator
Requirements of a launcher
- to be able to carry and restrain missiles in captive flight
- enable armed release or safe jettison
- aircraft stores managment system (SMS)
- pre - launch power supplies and information to missile
state the components of a typical GW launcher
outer housing assembly
electronics unit
mechanical assembly
safety pin
coolant gas bottle
arming units
snubbers (wedges)
‘L’ connectors
when would the fire button be pressed
when target is within range - “FIRE” button pressed
purpose of the 2 way umbilical of the P4
2 way data transfer
what is monitored by the launcher electronics unit
missile internal power unit
when the launcher electronics unit achieves the requirements met what will it do
launcher electronics unit issues motor ignition signal and arming signal if required
with regards to SEA SKUA what components make up the missile centre assembly
- an E-pack
- autopliot
- thermal batteries
- radar altimeter transmitter aerial
- the radar altimeter data processing unit
with SEA SKUA how is guidance achieved
semi-active homing in azimuth
Rad Alt for heigth control
what happens if SEA SKUA loses target lock
if radar lock is lost, the missile’s electronics and auto pilot will carry on the attack using stored information until the target is re-acquired (last known position)
with reference to SEA SKUA what are the modes of operation for the warhead
2 milli second delay (provides improved penatration/blast effect)
instantaneous operation on impact with target (to overcome threat of lightly constructed fast patrol craft during gulf operation)
what is the purpose of the SEA SKUA safe arming unit
isolate the warhead, physically or electronically
deliberately released armed or safe
initiate on impact with target or self destruct
how is control achieved
control surfaces are operated by four separate electrical motors, powered by the thermal battery
purpose of the MIDU in the SEA SKUA
successfully released the ignition of the motors is delayed until clear of the aircraft
inhibits motor ignition missiles release attitude is incorrect
visual indication of the ignition circuits condition
what are the indication colours of the MIDU
safe condition:
GREEN/WHITE diagonal stripes
unsafe (armed)
RED
safe but operated condition:
YELLOW/BLACK stripes
what is visible on the upper surface of the missile between the two rocket motors
ground safety pin/pennant
a sight tube for checking of visual display
green (safe - shorting plug)
black/yellow (arming plug)
what does the MIDU and SAU ensure
- deliberatly selected for release in an armed role
- release sequence is correct
- missiles attitude after release is correct
- warhead is not armed unless it is deliberately selected
what does the tactical datalink of the SEA VENOM do
- remain on control of up to 4 missiles at the same time
- positively identify intended targets
- re-designate targets while the missile is in flight
- perform a missile abort
- specify a precise aim point on the intended target/building
what is the propulsion system of the SPEAR CAP 3
liquid fuel turbojet propulsion system
what are the guidance modes of the FASGW (L) and why is it chosen
laser beam riding or laser designation
semi-active laser homing
impossible to jam works with low reflectivity targets (rubber boats)
what are the Paveway 4, 4 main components
P4 warhead
enhanced computer control group (ECCG)
P4 multi event hard target fuze (MEHTF)
bomb conversion kit
