final Flashcards
What is radar?
Radio detection and Ranging: system that permits the detection of an object by emitting electromagnetic pulses and capturing echos
What is air defence?
Air defence, as its name implies, is the act of safeguarding some protected asset or assets—specifically against threats from the air domain. More broadly, air defense plays a key role in providing some countries with the capacity to deny access to their proximity to adversaries.
What is the difference between localized and integrated air defence?
IADS: structure, equipment, personnel, procedures, and weapons used to counter the enemy’s airborne penetration of one’s own claimed territory. Rather than a single weapon or person, it is an amalgamation of elements, organized to minimize threats in the air domain. Thus, an effective IADS performs three functions—air surveillance, battle management, and weapons control. Of these, air surveillance alone includes five specific sub-functions: detect, initiate, identify, correlate, and maintain. A radar will “detect” an aircraft entering an IADS’s area of coverage, while the “initiate” function transforms radar returns into “tracks.” The “identify” function examines the track and categorizes it as friend, foe, or unknown. Finally, the “maintain” function allows for specific tracks to be continuously monitored.
What is the radar cross section?
The radar cross section (RCS) is a measure of how much a target reflects radar waves back to the radar antenna. It is a complex concept that depends on various factors such as the shape, size, and material properties of the target, as well as the frequency and polarization of the radar signal.
What is stealth and why is it important?
Stealth, or aircraft signature reduction, simply means an object, in this case an aircraft, that is difficult to detect or can only be detected at short range.
Stealth is difficult to defend against because it reduces the enemy’s ability to detect attackers; this complicates air defence efforts and reduces the time for adversaries to react effectively. In addition to increasing the crafts’ survivability, it reduced risk and losses of non-stealthy assets, surprised the enemy, and significantly improved the economy of force by allowing aircraft that would have been tasked for support operations to strike other targets.
What are the main ways to reduce observability to radar?
Stealth, (especially for land-based radars)concealment, either behind obstacles or behind earth’s curvature-> low altitude flying, jamming, chaff, spoofing
What is jamming? What is spoofing?
Jamming is about interference while spoofing is creating a vast emission of electromagnetic signals to ‘max up’ the capacity of the radar and its operator
Why are airborne radars important?
Not subjected to earth curvature and obstacles that allow low flying crafts to be undetected; longer range (land based ~400 km; airborne ~600-700 km)
What’s the main difference between long wavelength (or low frequency) and short wavelength (or high frequency) radar waves?
Low-frequency radar waves travel long distance (but they have low resolution). This is
identifcal to acoustics: basses (which have low frequency) travel much longer than
high pitches (this is why after you have left a concert, you can steal hear the basses far
from it).
What is sonar?
SOund Navigation And Ranging
Why is underwater acoustics so important?
Before the advent of sonar, detecting submarines was very difficult. Submarines
before WWII submarines were actually “submersible”, they were very slow
underwater, which meant that could not scout the ocean for targets, and they could
spend only limited amount of time underwater (batteries had limited endurance).
Hence, they had to resurface periodically to recharge their batteries by running their
diesel engines.
When on the surface, submarines were more vulnerable. To limit such vulnerability,
during World War II, submarines would generally be underwater during the day, to
avoid visual detection, and they would cruise on the surface at night to look for
targets.
What is anti-submarine warfare?
Anti-submarine warfare (ASW) is a branch of underwater warfare that uses surface warships, aircraft, submarines, or other platforms to find, track, and deter, damage, or destroy enemy submarines. The primary goal of ASW is to protect friendly shipping and coastal facilities from submarine attacks and to overcome blockades.
What is the difference between active and passive sonar?
Passive sonar works like the human ear: it listen the environment in search for cues. Because it caputres all the sounds, it captures also low frequency ones, which can travel at very long distance, in particular because of the deep sound channel (or sound fixing and ranging channel), which essentially traps acoustic waves (in deep water) and let them travels potentially thousands of kilometers.
The fielding of active sonar durign World War II changed underwater warfare, and it permitted to scan the waters for a couple of km from the source to look for potential enemy submarines. Active sonar worsk like radar, but rather than emitting electro-magnetic pulses it emits acoustic pulses and capture their echo (return) after encountering an object.
What is the difference between attack and ballistic-missile submarines
attack - more direct action + cruise missiles
ballistic - deterrence
Why are submarines considered the first “stealth” weapon system?
not visible by radar or sight which were the most prominent, effective and available detection methods of the time->
The answer, in a nutshell, is because they are stealthy: the challenge of detecting through human sight and sensors that are very effective in the atmosphere (radar, laser, thermal, infrared, etc.) makes them an a very effective threat, and hence an ideal platform for a multitude of tasks (coastal defense, conventional deterrent, nuclear deterrent, espionage missions, etc.).
How do modern submarines maintain their stealth and why is it important?
flow noise→ the noise that water/air makes when moved by the object. To avoid you either go slow (operational cost) or increase aerodynamics→ hydrodynamic shape to reduce flow noise
Cavitation→ propeller by rotating produce pressure→ bubbles that travel up→ can be detected→ An increasing number of more geometrically complex blades in propellers to reduce cavitation (cavitation is speed-dependent) and the replacement of propellers with pumpjets
Noise by the machinery inside→ need to reduce it and isolate from outside and the hull, especially for nuclear submarines (ex:Electric subs can be shut down, which means they make no noise. Nuclear cannot be shut down)
Personnel noise→ made by the people→ need to be isolated as well as devices to reduce noise (ex: rubber shoes)
What are the main ways to reduce observability to sonar?
reduce turbulence, reduce caviation,
reduce personnel noise, propellor shape, nuclear reactors
What’s the main difference between low-frequency and active-frequency sound waves?
passive sonar in the SOFAR (deep sea sound channel) where low frequency are transmitted for thousands of km; active frequency sound for active sonar-> they’re the ‘ping’ which then
Why is has the evolution submarine technology gone hand in hand with the evolution of unconventional (asymmetric?) strategies at sea?
Because before submarines, the dominant forces for strategies at sea were those of battle ships, submarines allowed for the weaker opponents (Germany) to prevent potential attacks by the British navy because they feared the presence of German submarines. The stealth aspect of submarines work to the advantage of asymmetric warfare because they allow for a weaker opponent to mount an attack on a more significant force using stealth.
What are competence-enhancing and competence-destroying innovations?
Some types of technological change reward existing skills, expertise, and production capabilities, thus reinforcing the leadership of incumbents, while other types of technological change require completely different skills, expertise, and production capabilities, thus allowing for the entry of new actors.
Conversely, competence-destroying technological change cancels out the advantage of dominant actors.
What does it mean that technological change has distributional effects?
That technological change has a distributional effect is of central importance for IR, because it questions one of the key premises of the Offense-Defense Balance, namely that the state of technology is a systemic variable, and hence constant across countries This means that technological change can significantly weaken some countries, while strengthening others, economically, politically, or militarily, and hence possibly also affect the system as a whole.
Why and how is technological change related to uncertainty?
As technology opens up new opportunities, it is difficult to understand and to identify the timing, the type, the direction, and the magnitude of technological change and of its implication—i.e., who will benet and who will lose, as well as when and to what degree. This is a key factor given that, since the 1990s at least, the dominant narrative has pushed private and public organisations alike to adopt new innovations. In fact, under some circumstances, it might be safer not to adopt an innovation, or to postpone its adoption until it is reliable and effective.
Why are some grand-strategic goals dependent on the state of technology?
Grand strategies are generally based on assumptions about what the state of technology allows and do not allow us to do. For this reason, technological change can render some grand-strategic goals obsolete.
Some grand-strategic goals such as primacy and latency are contingent on the state of technology, commercial or military.
What are dissuasion strategies?
Diplomatic efforts: Engaging in diplomatic talks and negotiations to persuade the opponent to reconsider their stance.
Economic sanctions: Imposing economic penalties or restrictions to pressure the opponent to change their behavior.
Military deterrence: Displaying military power or capabilities to deter the opponent from taking a particular action.
Psychological operations: Using propaganda, disinformation, or psychological manipulation to influence the opponent’s perceptions and attitudes.
International pressure: Building a coalition of international support to pressure the opponent to change their behavior.
Offering incentives: Providing rewards or benefits to the opponent to encourage them to abandon their goals or intentions.