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Dumb questions from a civilian: What is the overlap in military utility between a fighter plane and a drone? How important are top-gun style "dogfights" in mo

Dumb questions from a civilian: What is the overlap in military utility between a fighter plane and a drone? How important are top-gun style "dogfights" in modern warfare? If everyone has stealth aircraft, how do they even find eachother to fight? How do missiles work? More generally, what role(s) do fighters play in modern warfare? When was the last time the US used a fighter jet for something that a drone could not have done?

ansible 10y ago
1. There are not any UCAVs (unmanned combat aerial vehicle) currently deployed that have capabilities close to those of current-generation fighter aircraft. That is being worked on, though not at the level I would like to see. Current generation drones are (as far as I am aware) designed to be piloted remotely, and aren't really designed to shoot down other aircraft. 2. With missiles that can strike an enemy from beyond visual range [1], it is often argued that dogfighting is no longer important. Current generation missiles are supposed to be pretty good. 3. There are degrees of stealth, and improvements to detection systems also continue. As far as missiles go, people have generally had a hard time shooting down stealth aircraft, though it is possible. 4. Combat against other aircraft, and close air support (CAS), where the fighter is attacking ground targets. Modern jet fighters don't do a great job at CAS, with the exception of the A-10, because of operational cost (too high), speed (too high), and loiter time (too low). There have been proposals to deploy propeller-powered aircraft such as the Super Tucano for CAS, because enemy aircraft haven't been a problem in recent conflicts. 5. Probably yesterday... if you count flying patrols. [1] https://en.m.wikipedia.org/wiki/Beyond-visual-range_missile#Criticism https://en.m.wikipedia.org/wiki/Beyond-visual-range_missile#...
- Recurecur 10y ago
  "1. There are not any UCAVs (unmanned combat aerial vehicle) currently deployed that have capabilities close to those of current-generation fighter aircraft. That is being worked on, though not at the level I would like to see. Current generation drones are (as far as I am aware) designed to be piloted remotely, and aren't really designed to shoot down other aircraft." Right. There has been discussion of a drone version of the F-35. I couldn't find much recent discussion, which probably means it's now behind the veil of classification. One thing to remember is that as you need more speed, range, and payload that will be directly reflected in the size of the aircraft. Small drones can't carry a lot of weapons, fly particularly fast, or very far. http://www.washingtonpost.com/wp-dyn/content/article/2006/08/15/AR2006081501288.html http://www.washingtonpost.com/wp-dyn/content/article/2006/08... I read an interesting article fairly recently where Russian ideas for unmanned fighter aircraft were discussed - the approach there looks to be manned "leader" aircraft directing larger numbers of unmanned drones. This is probably how the West will go as well, since it's important to have local C&C in case communication systems are compromised. It also at least gives the appearance of "human in the loop" rather than fully autonomous lethal operations. "2. With missiles that can strike an enemy from beyond visual range [1], it is often argued that dogfighting is no longer important. Current generation missiles are supposed to be pretty good." While this is all highly classified, it's unlikely that any adversary's long-range radar guided missiles will work against the F-22 or F-35 (or B-2 for that matter) at anything like their maximum range. A guess would be that if the missile had a max range of 100 miles against a Gen4 target, it would have an effective range of 10 miles or less against a Gen5 target. The Achilles heel of stealth aircraft is IR detection. There is no getting around the laws of thermodynamics and waste heat. There are some mitigations that help, such as rectangular cross section engine exhausts, but LWIR missiles detect the thermal radiation from the rigid body (hardbody) of the aircraft and home in on that. Note the mention of the "backup" IR sensor (BTW the described system is quite interesting in other ways): http://www.popsci.com/china-new-long-range-air-to-air-missile http://www.popsci.com/china-new-long-range-air-to-air-missil... It is worth noting that having a high-quality IR sensor on a hypersonic missile is a very tough problem due to heating. "3. There are degrees of stealth, and improvements to detection systems also continue. As far as missiles go, people have generally had a hard time shooting down stealth aircraft, though it is possible." If you're able to locate the stealth aircraft in time, IR missiles can be effective. The problem is that it's likely the first realization you'll have a stealth aircraft is around is when it launches a missile at you. One virtue of sensor fusion and networked aircraft is that aircraft further back (including AWACS) can use radar, then deliver targeting information to aircraft closer to the enemy. The F-35 can also cue weapons from other platforms - recently there was a successful test where an F-35 successfully guided a Navy SM-6 SAM against an air target. The SM-6 has over a 200 mile range... http://nationalinterest.org/blog/the-buzz/lockheed-martins-f-35-the-us-navys-secret-missile-defense-18960 http://nationalinterest.org/blog/the-buzz/lockheed-martins-f...
  - pps43 10y ago
    > The problem is that it's likely the first realization you'll have a stealth aircraft is around is when it launches a missile at you. Stealth aircraft still reflect radiowaves, they just don't reflect them back at the source. This can be effectively countered by separating radar transmitter and receiver in space. It is also possible to use existing transmitters (e.g., FM radio, cell towers) to build passive radar that does not emit anything itself.
    - Recurecur 10y ago
      "Stealth aircraft still reflect radiowaves, they just don't reflect them back at the source. This can be effectively countered by separating radar transmitter and receiver in space." There are also radar absorbing materials and coatings involved, though to be sure they don't absorb everything. The modern curved stealth airframes also diffuse the return, weakening it considerably. "It is also possible to use existing transmitters (e.g., FM radio, cell towers) to build passive radar that does not emit anything itself." Sure, although stealth aircraft are most vulnerable to long wavelength radar, which lack precise positional detection. Also, if you're using cell/FM etc. transmitters, those are easily shut down by strikes on power stations, or EMP. An interesting, revolutionary approach is quantum radar, which uses entanglement to detect photon interaction with the target. It's pretty far from prime time though. http://www.popsci.com/china-says-it-has-quantum-radar-what-does-that-mean http://www.popsci.com/china-says-it-has-quantum-radar-what-d...
      - pps43 10y ago
        Diffusing the return is actually good for the radar. If all return goes in one direction and there happens to be no radar receivers in that direction, radar won't detect anything. With diffused return at least some of it is reaching the receivers. Cell tower signals have higher frequency than VHF, which makes position estimation easier. Cell towers will work for a few days even if power grid goes down. There are too many of them to take out individually. Nuclear blast has EMP powerful enough to burn them, but by that time you probably no longer need stealth. With access to baseband code in modern cell phones it might be possible to build distributed passive radar surreptitiously. There is enough processing power, exact time and location from GPS, and communication over LTE.
fapjacks 10y ago
Air superiority keeps your enemy from dropping ordinance on you when you're advancing along the highway towards the capital. It also lets you drop ordinance on enemy armor and artillery, two of the biggest impediments to advancing ground forces. As a former infantryman, fighters are one of those things that you really want on your side. They are really a powerful psychological weapon, too. I have a friend who is a fighter pilot and "dogfighting" in the Top Gun sense has gone the way of the Dodo bird. Fire and forget missiles are the way of the future -- and more specifically, fire and forget missiles from drone fighters. If the American military could take the men out of the fight and replace them with autonomous robots and drones, they wouldn't hesitate. Of course, it's not possible now, but it's just a matter of technology advancing to that point.
- Boothroid 10y ago
  Ordnance.
  - lostlogin 10y ago
    Both slow advances.
- valuearb 10y ago
  The air force is run by fighter jocks, that's why they are already hesitating to use drones which will be as effective as the F35 for a tenth the cost.
dalbasal 10y ago
It's hard to know, without a major conflict answer these questions in the field (or sky). Air forces played huge role in WW2. Fighters were important for establishing air control and that determined outcomes. There have been few examples since. The 1967 war between Israel & the Syrian-Egyptian alliance and follow up in 1973 were influential conflicts between modern (at the time) air forces. In 1967, Israel won the air-war early. This basically won the war and fighters played a primary role. In 1973, Egypt successfully established a forward front using ground forces. Their missile air-defence made this possible, missiles made fighters ineffective in a limited area. If modern missile defence can do this for a 100x larger area, fighters might be confined to a much smaller role. That was 45 years ago. Who knows where we are now, what's redundant and what's crucial. When WW2 broke out, there was a long process of figuring out what worked in a modern war. It's hard to know in advance. Big gun ships were thought to be very important, but aircraft carriers and smaller battle ships ended up being more important. The US, Russia etc haven't fought a modern enemy in 2 generations. That's like building factories for 40 years which may one day need to produce goods. There's a high likelihood you are building the wrong thing entirely.
- whazor 10y ago
  Planes are still useful for controlling air and ground. Maybe not against nations, but definitely against terrorist groups and unknown flying objects.
  - valuearb 10y ago
    Drones are becoming as useful fir ground support and are far more cost effective.
- tbonza 10y ago
  It's a good point. Terrorizing an urban population with $200 drones doesn't seem like an unrealistic scenario. How would a tool like the F-35 be used to combat this situation? I think it would be fairly useless. Here's a link to an article about a cheap drone being shot with a Patriot missile: http://www.bbc.com/news/technology-39277940 http://www.bbc.com/news/technology-39277940
ceejayoz 10y ago
> If everyone has stealth aircraft, how do they even find eachother to fight? How do missiles work? Stealth isn't like a Star Trek cloaking device - they're still detectable, just not as much. Lets them get closer to targets before being detected, but if you fly a B-2 right over a radar site it's likely to get picked up. Missiles can be guided by a more powerful ground radar or an AWACS aircraft, and some are capable of optical and heat-seeking operation.
Nokinside 10y ago
>How important are top-gun style "dogfights" in modern warfare? Modern medium-range air-to air missile (AMRAAM AIM-120D) has optimal launch distance (best probability of kill) roughly 100 km. (max range 160+ km). Short range IR-guided missiles have range 20-30 km. Optimal range closer to 20 km. While modern missiles can be launched from almost any position, good Pk (probability of kill) from long range is not realistic unless the fighter is flying high speed, at high altitude towards the target. Medium and long range missiles spend energy accelerating to maximum speed and climbing up to thinner atmosphere for their mid-course flight. Flying fast and high towards the enemy increases the range of the missile. After launching medium-range air-to air missile (AMRAAM) within 100 km it takes only 20 seconds before fighter meet at the close range where IR-quided missiles are used. F-35 have sustained rate of turn between 5-20 degrees per second (depending on altitude, speed, loading). Flying high speed at maximum altitude leaves little or no room to turn and keep standoff distance. If the enemies keeps coming there will be almost certain dogfight. The advantage of stealthy F-35 against conventional 4 generation fighter is that it can get radar lock from long range, and the missile can maintain that lock from longer distance. Being first in position to launch is huge advantage and it forces enemy to start evasive maneuvers. Enemy will adapt it's strategy against F-35 of course. IR-sensors help to negate some of the radar stealth advantage and the technology is advancing fast. Carrying more decoys, chaff helps also. Using drones in air combat will change many things. --- >If everyone has stealth aircraft, how do they even find eachother to fight? How do missiles work? IR-sensors are added into medium and long range missiles. This has not happened yet, but it's almost certain development.
- Nokinside 10y ago
  I should add that when two or more fighters engage in dogfight, their speed decreases dramatically and they become sitting ducks for other fighters.
dgudkov 10y ago
>How important are top-gun style "dogfights" in modern warfare? >If everyone has stealth aircraft, how do they even find eachother to fight? There are two major tasks when trying to shoot down an airplane: detecting it and bringing a missile to it. Detecting a stealth fighter is possible with a long wavelength radar[1]. The problem is that the precision of location it provides is not sufficient for targeting the airplane, because an air-to-air missile needs to be very close to target in order to shoot it down (think <10 meters). Short wavelength radars are typically used for targeting airplanes as they provide very precise location. But such radars can "see" stealth fighters only at very short distances, when it's too late to counteract. So the idea of fighting one stealth fighter with another would be a) bring our fighter into the approximate area where the hostile fighter is, and b) let the pilot figure out the enemy's exact location using an on-board short wavelength radar and/or FLIR [2]. Since (b) can happen at rather large distances (think 40-50kms) it is believed that a dogfight is very unlikely nowadays, because modern air-to-air missiles allow shooting down reliably the adversary long before two planes become close enough for a dogfight. [1] https://theaviationist.com/2014/03/27/vega-31-shot-down/ https://theaviationist.com/2014/03/27/vega-31-shot-down/ [2] https://en.wikipedia.org/wiki/Forward_looking_infrared https://en.wikipedia.org/wiki/Forward_looking_infrared >How do missiles work? There are two ways how missiles target airplanes. The problem with missiles is that they are too small to have a powerful radar sufficient for long-range targeting. Therefore one way is to "highlight" the target by a powerful radar (typically ground-based) so missiles can use the "reflected" signal for navigation. That's how long-range surface-to-air missiles typically work. Air-to-air missiles operate at shorter ranges and typically use infra-red detectors for navigation. Stealth fighters emit only slightly less heat radiation than regular fighter jets and therefore very vulnerable to IR targeting. I believe there are various combinations of both approaches, but that's another story.

ansible 10y ago

1. There are not any UCAVs (unmanned combat aerial vehicle) currently deployed that have capabilities close to those of current-generation fighter aircraft. That is being worked on, though not at the level I would like to see. Current generation drones are (as far as I am aware) designed to be piloted remotely, and aren't really designed to shoot down other aircraft. 2. With missiles that can strike an enemy from beyond visual range [1], it is often argued that dogfighting is no longer important. Current generation missiles are supposed to be pretty good. 3. There are degrees of stealth, and improvements to detection systems also continue. As far as missiles go, people have generally had a hard time shooting down stealth aircraft, though it is possible. 4. Combat against other aircraft, and close air support (CAS), where the fighter is attacking ground targets. Modern jet fighters don't do a great job at CAS, with the exception of the A-10, because of operational cost (too high), speed (too high), and loiter time (too low). There have been proposals to deploy propeller-powered aircraft such as the Super Tucano for CAS, because enemy aircraft haven't been a problem in recent conflicts. 5. Probably yesterday... if you count flying patrols. [1] https://en.m.wikipedia.org/wiki/Beyond-visual-range_missile#Criticism https://en.m.wikipedia.org/wiki/Beyond-visual-range_missile#...

Recurecur 10y ago
"1. There are not any UCAVs (unmanned combat aerial vehicle) currently deployed that have capabilities close to those of current-generation fighter aircraft. That is being worked on, though not at the level I would like to see. Current generation drones are (as far as I am aware) designed to be piloted remotely, and aren't really designed to shoot down other aircraft." Right. There has been discussion of a drone version of the F-35. I couldn't find much recent discussion, which probably means it's now behind the veil of classification. One thing to remember is that as you need more speed, range, and payload that will be directly reflected in the size of the aircraft. Small drones can't carry a lot of weapons, fly particularly fast, or very far. http://www.washingtonpost.com/wp-dyn/content/article/2006/08/15/AR2006081501288.html http://www.washingtonpost.com/wp-dyn/content/article/2006/08... I read an interesting article fairly recently where Russian ideas for unmanned fighter aircraft were discussed - the approach there looks to be manned "leader" aircraft directing larger numbers of unmanned drones. This is probably how the West will go as well, since it's important to have local C&C in case communication systems are compromised. It also at least gives the appearance of "human in the loop" rather than fully autonomous lethal operations. "2. With missiles that can strike an enemy from beyond visual range [1], it is often argued that dogfighting is no longer important. Current generation missiles are supposed to be pretty good." While this is all highly classified, it's unlikely that any adversary's long-range radar guided missiles will work against the F-22 or F-35 (or B-2 for that matter) at anything like their maximum range. A guess would be that if the missile had a max range of 100 miles against a Gen4 target, it would have an effective range of 10 miles or less against a Gen5 target. The Achilles heel of stealth aircraft is IR detection. There is no getting around the laws of thermodynamics and waste heat. There are some mitigations that help, such as rectangular cross section engine exhausts, but LWIR missiles detect the thermal radiation from the rigid body (hardbody) of the aircraft and home in on that. Note the mention of the "backup" IR sensor (BTW the described system is quite interesting in other ways): http://www.popsci.com/china-new-long-range-air-to-air-missile http://www.popsci.com/china-new-long-range-air-to-air-missil... It is worth noting that having a high-quality IR sensor on a hypersonic missile is a very tough problem due to heating. "3. There are degrees of stealth, and improvements to detection systems also continue. As far as missiles go, people have generally had a hard time shooting down stealth aircraft, though it is possible." If you're able to locate the stealth aircraft in time, IR missiles can be effective. The problem is that it's likely the first realization you'll have a stealth aircraft is around is when it launches a missile at you. One virtue of sensor fusion and networked aircraft is that aircraft further back (including AWACS) can use radar, then deliver targeting information to aircraft closer to the enemy. The F-35 can also cue weapons from other platforms - recently there was a successful test where an F-35 successfully guided a Navy SM-6 SAM against an air target. The SM-6 has over a 200 mile range... http://nationalinterest.org/blog/the-buzz/lockheed-martins-f-35-the-us-navys-secret-missile-defense-18960 http://nationalinterest.org/blog/the-buzz/lockheed-martins-f...
- pps43 10y ago
  > The problem is that it's likely the first realization you'll have a stealth aircraft is around is when it launches a missile at you. Stealth aircraft still reflect radiowaves, they just don't reflect them back at the source. This can be effectively countered by separating radar transmitter and receiver in space. It is also possible to use existing transmitters (e.g., FM radio, cell towers) to build passive radar that does not emit anything itself.
  - Recurecur 10y ago
    "Stealth aircraft still reflect radiowaves, they just don't reflect them back at the source. This can be effectively countered by separating radar transmitter and receiver in space." There are also radar absorbing materials and coatings involved, though to be sure they don't absorb everything. The modern curved stealth airframes also diffuse the return, weakening it considerably. "It is also possible to use existing transmitters (e.g., FM radio, cell towers) to build passive radar that does not emit anything itself." Sure, although stealth aircraft are most vulnerable to long wavelength radar, which lack precise positional detection. Also, if you're using cell/FM etc. transmitters, those are easily shut down by strikes on power stations, or EMP. An interesting, revolutionary approach is quantum radar, which uses entanglement to detect photon interaction with the target. It's pretty far from prime time though. http://www.popsci.com/china-says-it-has-quantum-radar-what-does-that-mean http://www.popsci.com/china-says-it-has-quantum-radar-what-d...
    - pps43 10y ago
      Diffusing the return is actually good for the radar. If all return goes in one direction and there happens to be no radar receivers in that direction, radar won't detect anything. With diffused return at least some of it is reaching the receivers. Cell tower signals have higher frequency than VHF, which makes position estimation easier. Cell towers will work for a few days even if power grid goes down. There are too many of them to take out individually. Nuclear blast has EMP powerful enough to burn them, but by that time you probably no longer need stealth. With access to baseband code in modern cell phones it might be possible to build distributed passive radar surreptitiously. There is enough processing power, exact time and location from GPS, and communication over LTE.

fapjacks 10y ago

Air superiority keeps your enemy from dropping ordinance on you when you're advancing along the highway towards the capital. It also lets you drop ordinance on enemy armor and artillery, two of the biggest impediments to advancing ground forces. As a former infantryman, fighters are one of those things that you really want on your side. They are really a powerful psychological weapon, too. I have a friend who is a fighter pilot and "dogfighting" in the Top Gun sense has gone the way of the Dodo bird. Fire and forget missiles are the way of the future -- and more specifically, fire and forget missiles from drone fighters. If the American military could take the men out of the fight and replace them with autonomous robots and drones, they wouldn't hesitate. Of course, it's not possible now, but it's just a matter of technology advancing to that point.

Boothroid 10y ago
Ordnance.
- lostlogin 10y ago
  Both slow advances.
valuearb 10y ago
The air force is run by fighter jocks, that's why they are already hesitating to use drones which will be as effective as the F35 for a tenth the cost.

dalbasal 10y ago

It's hard to know, without a major conflict answer these questions in the field (or sky). Air forces played huge role in WW2. Fighters were important for establishing air control and that determined outcomes. There have been few examples since. The 1967 war between Israel & the Syrian-Egyptian alliance and follow up in 1973 were influential conflicts between modern (at the time) air forces. In 1967, Israel won the air-war early. This basically won the war and fighters played a primary role. In 1973, Egypt successfully established a forward front using ground forces. Their missile air-defence made this possible, missiles made fighters ineffective in a limited area. If modern missile defence can do this for a 100x larger area, fighters might be confined to a much smaller role. That was 45 years ago. Who knows where we are now, what's redundant and what's crucial. When WW2 broke out, there was a long process of figuring out what worked in a modern war. It's hard to know in advance. Big gun ships were thought to be very important, but aircraft carriers and smaller battle ships ended up being more important. The US, Russia etc haven't fought a modern enemy in 2 generations. That's like building factories for 40 years which may one day need to produce goods. There's a high likelihood you are building the wrong thing entirely.

whazor 10y ago
Planes are still useful for controlling air and ground. Maybe not against nations, but definitely against terrorist groups and unknown flying objects.
- valuearb 10y ago
  Drones are becoming as useful fir ground support and are far more cost effective.
tbonza 10y ago
It's a good point. Terrorizing an urban population with $200 drones doesn't seem like an unrealistic scenario. How would a tool like the F-35 be used to combat this situation? I think it would be fairly useless. Here's a link to an article about a cheap drone being shot with a Patriot missile: http://www.bbc.com/news/technology-39277940 http://www.bbc.com/news/technology-39277940

ceejayoz 10y ago

> If everyone has stealth aircraft, how do they even find eachother to fight? How do missiles work? Stealth isn't like a Star Trek cloaking device - they're still detectable, just not as much. Lets them get closer to targets before being detected, but if you fly a B-2 right over a radar site it's likely to get picked up. Missiles can be guided by a more powerful ground radar or an AWACS aircraft, and some are capable of optical and heat-seeking operation.

Nokinside 10y ago

>How important are top-gun style "dogfights" in modern warfare? Modern medium-range air-to air missile (AMRAAM AIM-120D) has optimal launch distance (best probability of kill) roughly 100 km. (max range 160+ km). Short range IR-guided missiles have range 20-30 km. Optimal range closer to 20 km. While modern missiles can be launched from almost any position, good Pk (probability of kill) from long range is not realistic unless the fighter is flying high speed, at high altitude towards the target. Medium and long range missiles spend energy accelerating to maximum speed and climbing up to thinner atmosphere for their mid-course flight. Flying fast and high towards the enemy increases the range of the missile. After launching medium-range air-to air missile (AMRAAM) within 100 km it takes only 20 seconds before fighter meet at the close range where IR-quided missiles are used. F-35 have sustained rate of turn between 5-20 degrees per second (depending on altitude, speed, loading). Flying high speed at maximum altitude leaves little or no room to turn and keep standoff distance. If the enemies keeps coming there will be almost certain dogfight. The advantage of stealthy F-35 against conventional 4 generation fighter is that it can get radar lock from long range, and the missile can maintain that lock from longer distance. Being first in position to launch is huge advantage and it forces enemy to start evasive maneuvers. Enemy will adapt it's strategy against F-35 of course. IR-sensors help to negate some of the radar stealth advantage and the technology is advancing fast. Carrying more decoys, chaff helps also. Using drones in air combat will change many things. --- >If everyone has stealth aircraft, how do they even find eachother to fight? How do missiles work? IR-sensors are added into medium and long range missiles. This has not happened yet, but it's almost certain development.

Nokinside 10y ago
I should add that when two or more fighters engage in dogfight, their speed decreases dramatically and they become sitting ducks for other fighters.

dgudkov 10y ago

>How important are top-gun style "dogfights" in modern warfare? >If everyone has stealth aircraft, how do they even find eachother to fight? There are two major tasks when trying to shoot down an airplane: detecting it and bringing a missile to it. Detecting a stealth fighter is possible with a long wavelength radar[1]. The problem is that the precision of location it provides is not sufficient for targeting the airplane, because an air-to-air missile needs to be very close to target in order to shoot it down (think <10 meters). Short wavelength radars are typically used for targeting airplanes as they provide very precise location. But such radars can "see" stealth fighters only at very short distances, when it's too late to counteract. So the idea of fighting one stealth fighter with another would be a) bring our fighter into the approximate area where the hostile fighter is, and b) let the pilot figure out the enemy's exact location using an on-board short wavelength radar and/or FLIR [2]. Since (b) can happen at rather large distances (think 40-50kms) it is believed that a dogfight is very unlikely nowadays, because modern air-to-air missiles allow shooting down reliably the adversary long before two planes become close enough for a dogfight. [1] https://theaviationist.com/2014/03/27/vega-31-shot-down/ https://theaviationist.com/2014/03/27/vega-31-shot-down/ [2] https://en.wikipedia.org/wiki/Forward_looking_infrared https://en.wikipedia.org/wiki/Forward_looking_infrared >How do missiles work? There are two ways how missiles target airplanes. The problem with missiles is that they are too small to have a powerful radar sufficient for long-range targeting. Therefore one way is to "highlight" the target by a powerful radar (typically ground-based) so missiles can use the "reflected" signal for navigation. That's how long-range surface-to-air missiles typically work. Air-to-air missiles operate at shorter ranges and typically use infra-red detectors for navigation. Stealth fighters emit only slightly less heat radiation than regular fighter jets and therefore very vulnerable to IR targeting. I believe there are various combinations of both approaches, but that's another story.