Air to Air Missiles Flashcards
Discuss and List IR target detection factor: aircraft heating.
Exhaust plume
Hot metal
Reflected Energy
Aerodynamic heating
Discuss and List IR target detection factor: the effects of background IR sources
(FOOTSTOMP)
BENIGN: Cool background. No competition with target IR signal.
Determined by seeker sensitivity.
EX: Blue sky, night, dark clouds, choppy water
ADVERSE: Hot background. Competing IR sources with target signal.
IR envelope determined by seeker discrimination capability and S/N ratio.
EX: Hot Desert, Sunlit clouds, sun, sun reflection on smooth water.
Discuss and List IR target detection factor: atmospheric attenuation on target acquisition.
Due to conditions that partially absorb or totally block IR energy such as moisture, dust, smoke, clouds, chemical compounds.
State the primary purpose of the detector in an IR guided A/A missile.
(FOOTSTOMP)
Converted MODULATED IR energy to an electrical signal.
Discuss the properties of different detector materials.
Wavelength=AA at which the missile can be fired
Sensitivity=Lock-on range
List types of detector materials.
Lead Sulfide (PbS) Lead Selenide (PbSe) Indium Antimonide (InSb)
State why detector materials are cooled
Improves detector sensitivity
Lowers require threshold relative to background radiation.
Methods of cooling a detector
Electrical
Cryogenic Gas
Discuss how a reticle is used to create Amplitude Modulation (AM) and Frequency Modulation (FM) signals.
AM: Measure the AMOUNT of IR energy passing through each individual transparent spoke of the reticle.
FM: Measures how much TIME IR energy spends on each individual transparent spoke of the reticle.
Discuss spin scan reticles and list their disadvantages.
Spin scan spins around the center of reticle.
Spin scan (AM) Disadvantages: Null area in center of the reticle, Vulnerable to IR jammers, flares in FOV longer.
Discuss conical scan reticles and list their advantages.
Conical scan spins around the target.
Conical Scan (FM) Advantages: More precise tracking of target, seeker continuously sees target, more resistant to IR jammers, flares fall out of FOV quicker.
Discuss imaging arrays in IR-Guided a/a missiles
Focal Plane Array (FPA) is thousands of detector elements (no reticle). Creates and IR picture. Increased sensitivity, high resolution, robust IRCCM.
List the three steps involved in IR-guided missile IRCCM
FOOTSTOMP
Detect
Confirm
Counter
Discuss different IRCCM techniques
FOOTSTOMP
Response: Memory, step to another technique
FOV: Small instantaneous FOV or electronic FOV (never see the flare)
Spatial: Ability to discern two separate IR sources in the FOV
Kinematic/temporal: Assumes flares fall backwards (biases seeker towards forward target)
Spectral: multiple detectors look in different wavelengths.
Imaging systems: If it doesn’t look right…
Discuss semiactive radar missile guidance, state the primary characteristic.
(FOOTSTOMP)
Missile has a radar receiver but no transmitter. Target is illumincated by Continuous wave (CW) or High Powered PRF (HPRF) from launching aircraft.
Characteristic: Aircraft Radar Tracks the target while the missile homes in on the reflected radar energy.
Discuss semiactive radar missile guidance, state the primary characteristic.
(FOOTSTOMP)
Missile has a radar receiver but no transmitter. Target is illuminated by Continuous wave (CW) or High Powered PRF (HPRF) from launching aircraft.
Characteristic: Aircraft Radar Tracks the target while the missile homes in on the reflected radar energy.
List semiactive radar missile guidance inherent advantages and disadvantages.
(FOOTSTOMP)
Advantages:
- resistant to EA designed to deny range information
- Can be guided almost immediately after launch-decreases minimum range
- Can compute its own course corrections
Disadvantages:
- Requires reference Doppler be sent to the missile before launch
- Must maintain lock onto the target Doppler
- Missile that requires seeker lock-on before launch limits maximum range
- Shooter must maintain target lock throughout missile TOF
Discuss active radar missile guidance, state the primary characteristic.
Missile is sent information of target from launching aircraft by datalink until missile is close enough to target to tx/rx itself.
Primary Characteristic: Missile has its own transmit and receive radar.
List active radar missile guidance inherent advantages and disadvantages.
(FOOTSTOMP)
Advantages:
- Difficult to jam
- Launch and leave capability
- multitargeting
Disadvantages:
- Complex
- Jamming against TTR may be effective prior to missile radar acquiring target.
Discuss different A/A missile control fin layouts, thrust vector control (TVC), and rocket motors.
Tail Control: More effective at high AOA (when missile is slow)
Canard Control: Most effective at low AOA (when missile is fast)
Thrust Vector Control (TVC): Six types of TVC. Controlling movement by altering thrust direction.
Rocket Motors: Four types. Different types allow for different burn rates and speed.
Describe the characteristic of different missile flight profiles
Three types of missile flight profile:
Lag: missile points behind the target
Pure: missile points at the target
Lead/pro-nav: missile points ahead of target.
Discuss and list considerations in A/A missiles employment
Motor: Only burns for a few seconds, then begins to slow down
Drag: Higher or lower drag affect range and speed.
Launch to Eject (LTE) delay: After launch command their is a finite amount of time to when missile actually launches
Arming Delays: after launching there is a finite amount of time until missile is fully armed
guidance enable: missile flies straight before beginning to maneuver
Guidance Life: internal power source only provides power for so long
Fuzing: is the fuzing fast enough to detonate
Missile Maneuverability: can the missile maneuver to intercept the target.
List factors that drive minimum and maximum employment ranges for A/A missiles (DISCUSS IS A ANOTHER QUESTION)
(FOOTSTOMP)
Minimum range considerations:
- Launch to eject (LTE) delays
- Guidance enable
- arming delays
- fuzing
- missile maneuverability
- gimbal limits
Maximum range considerations:
- Target detection
- Motor (endgame)
- Drag (Endgame)
- Guidance life
- Altitude
List the different fin controls.
Tail
Canard
Wing
Thrust Vector Control (TVC)
State why proportional navigation is advantageous.
Most energy efficient.
Maximize missile range
Maximizes missiles endgame maneuverability.
What are the effects of altitude on A/A missiles
FOOTSTOMP
- High-to-low increases range
- Low-to-high decreases range
- Missiles not as maneuverable at high altitude
To exploit a targets IR and Radar energy, missile must…
IR:
- Sense Target–Detector
- Track Target–Optical System
- Hit Target–Flight Profile
- Ignore–IRCCM
Radar:
- Sense Target–Shooter’s radar
- Track Target–shooter’s radar/onboard radar
- Hit Target–Guidance/tracking/flight profile
- Ignore–EP
To exploit a targets IR and Radar energy, missile must…
IR:
- Sense Target–Detector
- Track Target–Optical System
- Hit Target–Flight Profile
- Ignore flares–IRCCM
Radar:
- Sense Target–Shooter’s radar
- Track Target–shooter’s radar/onboard radar
- Hit Target–Guidance/tracking/flight profile
- Ignore EA–EP
