Weapons Flashcards
What is the process for deriving weapons grade U-235
U-238(uranium ore) – yellowcake — converted to uranium hexafuoridengas and mechanically separated until ~90% U-235 – weapons grade U-235 isotope
What changes has happened in the US stockpile and nuke yield per weapon
Yield has gone up and stockpile has gone down
What is the process for deriving weapons grade Pu-239
U-238 – bombarded wit neutrons in a nuclear reactor producing Pu-239 contaminated with ever-increasing amounts of Pu-240 and Pu-241 – weapons grade Pu-239 isotope
Describe fission
The splitting of heavy nuclei
U-235 and Pu-239 fission isotope
Describe fusion
Joining of light nuclei
Deuterium and tritium isotope of hydrogen
*How is detonation achieved with fission
- the gun assembly or implosion method brings u-235 or pu-239 fissile material to supercriticality
- neutrons are injected into the supercriticality material
- u-235 or pu-239 undergoes a fission chain reaction
- bomb case ruptures, nuclear detonation occurs
*How is detonation achieved in fusion
- primary fission event creates heat and pressure within the bomb case
- heat and pressure compresses fusion secondary causing deuterium and tritium isotopes to fuse
- deuterium and tritium fusion releases flood of neutrons causing subsequent fission
Easiest to achieve with low numbers of protons such as the isotopes of hydrogen
What are the thermal effects on people
Flash blindness
Flash burns of second degree out to 15 miles, third degree burns out to 8 miles.
*What are the properties of burst, in an air burst
Blast 50%
Thermal 35%
Initial radiation 5%
Residual radiation 10%
What are thermal effects on structures
Threshold ignition of light flammable out to 10 mi
Extensive fire damage out to 8.5 mi
What are the effects of blast effects on people
Collapse lungs, rupture ear drums and smash into objects
what are the blast effect on structures
concrete structures out to 5 mi, wood frame collapse out to 8 mi
*What are the different enhanced effects of air burst, burst, and subsurface
- Air burst enhances blast and thermal effects
- Ground burst enhances nuclear radiation effects
- subsurface burst enhances ground shock
*Describe the B61 Nuclear bomb
the only nuke for fighters and bomber variants
*Describe the B83 nuclear bomb
a bomber weapon only
*Describe the W80 warhead
Warhead for the AGM-86B Air Launched Cruise Missile
Define Aspect Angle (AA)
Measurement from target’s tail at (0 degrees AA) and goes to attacker. Will not be more than 180 degrees from the target’s tail.
The heading of the attacker is irrelevant.
*Describe W-78 and W-87 warheads
Both for the ICBM Minuteman III
Define Heading Crossing Angle (HCA)
Angular difference between target’s and attacker’s noses
Define Line of Sight as it applies to Air-to-Air Missiles
Measured from the attack’s nose to target
List the background effects of (Benign: cool background) on IR acquisition
No competition with target IR signal
Envelope determined by seeker sensitivity
Seen with: Blue sky, night, dark clouds, choppy water
List the effects of background on (adverse: hot background) for IR acquisition
Competing IR sources with target signal
IR envelope determined by seeker discrimination capability and Signal to Noise ratio
Seen with: hot desert, sunlit clouds, sun, sun reflection on smooth water
Define atmospheric attenuation
Any atmospheric condition that partially absorbs or totally blocks IR energy such as mostiure, dust, smoke, clouds
List and describe types of detector materials
Lead Sulfide (PbS) Lead Selenide (PbSe) Indium Antimonide (InSb)
PbS has a small area of coverage uncooled from 2 - 3
PbSe has the smallest area of coverage uncooled from 3 - 3.5
InSb has the largest area of coverage cooled from 3.5 - 5.5
*What is the primary purpose of a detector in an IR guided missile
Converts MODULATED IR energy to an electrical signal
Detectors are important because
- wavelength = AA at which missile can be fired
- sensitivity = lock-on range
- missile inherits detector’s weaknesses
Why is it important to cool the detector of an IR missile
What are the methods of cooling
Improves detector sensitivity, and lowers required threshold relative to background IR radiation.
Methods of cooling are Electrical, cyrogenic gas (Argon, Helium, Nitrogen).
Discuss how Amplitude Modulation (AM) Reticles work
Measures the amount of IR energy passing through each individual transparent spoke of the reticle.
So when target is centered in reticle all amounts of energy will be equal, but when off centered the sectors with high energy indicate the target is in that direction/sectors.
*State the primary purpose of the reticle in an IR guided missile
Modulate IR energy via opaque and clear tracking windows and varies output of the electrical signal sent to the GCS based upon where the IR energy hits the retical
…modulates IR energy so a detector can convert it into an electrical signal
Discuss Frequency Modulation (FM) Reticle
Measures how much TIME IR energy spends on each individual transparent spoke of the reticle.
So the sectors with less energy indicate the target is in that direction.
Discuss spin scan and list their disadvantages
Spinning reticle/ one detector to filter out clutter
disadvantage:
- null area in center of reticle
- Undulating flight path
- Vulnerable to IR jammers
- Simple AM processor
- Flares in FOV longer
Discuss conical scan and their advantages
Spinning mirror, fixed reticle one detector
Advantages:
- More precise tracking of target
- Seeker continuously ‘sees’ target
- More resistant to IR jammers
- Flares fall out of FOV quicker
Discuss Imaging Array in IR missiles
Focal Plane Array: thousands of detector elements
-Creates an IR picture: increased sensitivity; greater lock-on range. High resolution; robust IRCCM.
List three steps of involved in IR guided missile IRCCM
- Detect
- sharp rise in IR energy (heat/intensity)
- sudden change in kinematics (flare falls away) - Confirm
- check increase in intensity in another IR band - Counter
- response: memmor, AGC protect, step to another techique, ability to discern two separate IR sources in the FOV.
Discuss different IRCCM techniques
- small FOV: with a wide FOV missile will see flare and acft, will small FOV will only see acft.
- Bias ahead: missile will lead acft slightly to limit ability to see flare fall away.
- Push-pull: “pull” towards the target, “push” away from flare.
- Sector attenuation: trailing sector is filtered out, to ignore flare.
What are advantages of semi-active radar guidance for A-A missiles
- Resistant to EA designed to deny range information
- Can be guided almost immediately after launch - decreases min range
- can compute its own course corrections
- accurate a longer ranges
*Discuss semi-active guidance for A-A guidance missiles
Aircraft radar tracks the target while the missile homes in on the reflected radar energy.
-Missile has a radar receiver but no transmitter
What are disadvantages of semi-active radar guidance for A-A missiles
- Requires reference Doppler be sent to the missile before launch
- Must maintain lock onto the target doppler
- Chaff and beam maneuvers may cause radar or missile to break lock
- Shooter must maintain target lock throughout the missile TOF
- Missile that requires seeker lock-on before launch limits max range
What are advantages of Active guidance for A-A missiles
- Accurate a long range; independent of TTR once missile goes active
- Difficult to jam
- launch and leave capability
- allows multitargeting
*Discuss active guidance for A-A missiles
Missile has its own transmit-and receive radar.
Missile contains a radar transceiver and the electronics necessary to find and track it target autonomously.
-Active only during terminal phase of flight; midcourse phase usually employs semiactive or command guidance
What are disadvantages of Active guidance for A-A missiles
- complex
- jamming against TTR may be effective prior to missile radar acquiring target
Discuss the type of fin layouts, and what they are better for
Tail control: more effective at high AOA than canard control when missile is slow
Canard control: most efficient at low AOA when missile is fast
What are the three types of missile flight profiles for pursuit course
Lag - missile points behind the target
Pure - missile points at the target
Lead/pro nav - missile points ahead of the
What are the two types of A-A warheads
Continuous rod = expanding circle of a metal rod
Blast/Fragmentation = expanding circle of frag
What are the factors that effect minimum range for Forward-Quarter Performance of A-A missiles
- LTE delays
- Arming delays
- Fuzing
- Missile maneuverability
- Gimbal limits
*What are the factors that effect Maximum range for Forward-Quarter Performance of A-A missiles
- Detection: IR acquisition/ radar limitations
- Moto
- Drag
- Guidance life (battery)
What are the factors that effect engagements for Beam Performance of A-A missiles
- Gimbal limits
- Maneuverablity
- Rocket motor (vectored thrust)
- LTE delays
- Arming delays
What are the factors that effect Maximum range for Rear-Quarter Performance of A-A missiles
- Detection
- Motor
- Drag
- Guidance life
What are the factors that effect Minimum range for Rear-Quarter Performance of A-A missiles
- LTE delays
- Fuzing
- Missile maneuverablity
- Gimbal limits
*Define F-pole
The range from fighter to target when missile impacts target
*Define E-pole
The minimum range from a threat aircraft that a drag can be accomplished to kinematically defeat any missile the bandit could have launched. synonymous with Minimum abort range (MAR)
*Define A-pole
Range from the fighter to the target when active missile acquires the target with its own radar and requires no support from the launching aircraft
What is a detonation and a deflagration
Detonation: supersonic propagation wave speed
Deflagration: a rapid combustion; propagation wave is less than the speed-of-sound
*Define Minimum notch range (aka N-pole)
The minimum range from a threat aircraft that a notch maneuver can be accomplished.
-target can maneuver sufficiently to get into the notch before missile arrives.
What are the three steps of the Bomb Explosive Train
- Detonator (fuze)
- Booster (intermediate charge)
- Main charge
*What are the five High-Explosive Weapons Effects
- Blast/shock
- Fragmentation
- Cratering/ penetrate hard targets
- Armor penetration
- Incendiary
What are characteristics of Mk-82
- 500 lb GP bomb
- Fairly good blast/frag, poor penetration/incendiary/armor pen
- Mk-82 low-drag (slick)
- Mk-82 high-drag (retarded)
- Mk-82 AIR (chute)
- Mk-62 Quickstrike (mine)
- GBU-12/-38/-54 (guided)
*What is the penetration ROT for the Mk-82
1 ft of reinforced concrete
What are characteristics of Mk-83
- 1000 lb GP
- Mostly used by the navy
- Mk-83 LD/HD
- Mk-83 Quickstrike (mine)
- GBU-32 JDAM
- GBU-16 LGB (Navy)
What are characteristics of Mk-84
- 2000 lb GP
- Best GP for penetration, blast, and cratering; poor incendiary and armor pen
- Mk-84 LD/AIR
- GBU-10,GBU-24/B (LGB)
- GBU-31(V)1 (JDAM)
*What is the penetration ROT for a Mk-84
3 ft reinforced concrete
*What are characteristics and penetration ROT for BLU-109
- Pen ROT:6 ft reinforced concrete
- 2000 lb with 535 lb explosive weight
*What are characteristics and penetration ROT for BLU-113
- > 22 ft of reinforced concrete
-5000 lb with 625 lb explosive weight
-
List the four fuze function methods
- Time
- Proximity
- Impact
- Hydrostatic
What is the purpose of the Mk-130 Quickstrike kit
Converts the Mk-82/-83 into a land or shallow water mine (water less than 100 ft)
*What is the CBU-87 Combined effect munition (CEM) best at
Most versatile CBU with armor-piercing fragmentation and incendiary effects.
*What is the CBU-89 Gator best at
Air-delivered minefield with counter cleanup capability
*What is the CBU-97 Sensor Fuzed Weapon (SFW) best at
Capability against moving vehicles.
WCMD is CBU-105
What are basics of AGM-65
- Shaped-charge penetrator
- 125 lb warhead, 85 lb of explosive
- small, hard targets: tanks, armored vehicles
What are the weapons effects of the AGM-114P-4
Dual warheads effective against armor
-precursor warhead to defeat explosive reactive armor, main warhead to defeat base armor.
What are the weapons effects of the AGM-114N-4
Thermobaric warhead, penetration is kinetic only, detonation is blast/frag/incediary
*What are advantages of tactical missiles (AGM-65/-114)
Precision accuracy
Standoff from small-arms and AAA threats
Relatively simple to use
Can hit moving targets
What are disadvantages of tactical missiles (AGM-65/-114)
Weather dependant
battlefield obscurant may impede guidance
relatively small warheads
*What are the two primary variants of Paveway II
GBU-12 based on Mk-82
GBU-10 based on Mk-84 or BLU-109
What are Paveway II (GBU-12/-10) employment considerations
- accurate, low collateral damage
- easy mission planning
- limited standoff
- require fair weather
- designator must support through TOF
*What are advantages of Laser-Guided Bombs
Standoff from small-arms & AAA threats Relatively simple to use Man-in-the-loop to impact Accurate weapon with real-time hit assessment Can hit moving targets
*What are disadvantages of Laser-Guided Bombs
Shorter standoff ranges relative to boosted weapons
Requires close-in designator support
LOS for weapon and designator must be accommadated
Weather/ battlefield obscurants may impede guidance
*What factors determine accuracy of GPS-aided, inetrial-guided weapons
- Navigation errors
- Guidance and control errors
- Target location errors (most signficant)
- Accuracy of target coordinates
- What is the basic concept of operations of GPS-aided munitions
The Guidance Control Unit (GCU) provide accurate guidance in both GPS-aided INS modes of operation and INS-only modes of operation
-INS guided/ GPS aided - autonomously guided to target, guided by coupling GPS.
*What are advantages of GPS-aided munitions
Standoff from small-arms, AAA, and short range SAMs
Adverse weather and battlefield obscurant possible
Multiple deliver platforms
Multiple weapons/aim points per pass
*What are the disadvantages of GPS-aided Munitions
No man in the loop after release
GPS jamming may impede guidance
Cannot hit moving targets
*List all the penetration characteristics of GP munitions
Mk-82 = 1 ft Mk-84 = 3 ft BLU-109 = 6 ft BLU-113 = 22 ft
*Match the three CBUs to their effects
CBU-87 = Combo Effect Munition (frag, blast, armor pen, incendiary)
CBU-89 - GATOR (mines)
CBU-97 - Sensor fused weapon (armor pen, moving vehicles)
*What are the types and effects of nukes
- Fission and fusion
- Thermal, blast, radiation
