[Goose]

What I do not understand at all is how effective Mainstay, or AWACS aircrafts are at picking up incoming missles, aircraft, or whatever, flying low in the weeds so to speak.

The short answer is very effective, subject to certain assumptions. I don't know the exact detailed capability of an A-50, but even assuming it is comparable to a late 1990s AWACS, it has a very good Digital Moving Target processor that uses the coherent Doppler shift in the radar returns from moving targets to make them absolutely stand out from the ground clutter. These platforms can even see cars on the freeway if they turn the low speed limit down far enough. The assumptions are 1) the target has a relative velocity component in it's course that is large enough to be detected, and 2) the target has a radar cross section large enough to be detected. The second requirement can be greatly affected by building a "stealth" cruse missile, which both we and the Russians (e.g. KH-101) have done. However, the physical size of most cruise missiles is such that the X band radar will see a missile when it would not see an aircraft of similar stealth. It has to do with the mode of reflection involved. That is one reason (of many) why the  E-7 Wedgetail operating in L band is such a high priority acquisition for the USAF. The USN was very smart (or lucky) in the original design of the E-2. Its radars, including APS-145 (https://www.radartutorial.eu/19.kartei/0...86.en.html) and the latest and greatest APY-9 (https://www.radartutorial.eu/19.kartei/0...83.en.html) operate just below P band.

BI recently had an article how we are now giving Ukraine a long range cruise missle that  has a range of 200 miles.  I am not sure how the Tomahawk missles feels about that.  200 miles is hardly a long range weapon.

The Tomahawk engine will just be warmed up at 200 miles :-).

I have seen articles that indicated that the S400 can find things flying down in the weeds, say  100 to 200 ft above mean ground level about 45 km out.  Can it then intercept that incoming missles in the time left if the incoming weapon is say moving at 500 mph?  Seems to me there is a very good chance that the incoming weapon would hit you before you hit it.

45 km is not literally correct. The radar horizon (without refraction) for a radar antenna located 10 feet above the ground and a cruise missile at 200 ft is 34.1 km. If the radar is at 20 ft in the air the horizon is 36.7 km. At 926 kph the 36.7 km will be covered in 142.7 seconds. Obviously the intercept needs to occur well away from the S400 to avoid fragment damage. Can an S400 accomplish this? The answer is a very qualified yes. The S400 does have an "automatic" mode that could in theory launch the missile. How well that actually works is an open question. The Russians tend to prefer a "man in the loop" operation. It is also pretty risky leaving a missile battery in full automatic mode for a long period of time. It is probable there is a non-zero false alarm rate. There are "red on red" issues at the very least, especially because supposedly both Russia and Ukraine aren't using the IFF much if at all. Under normal circumstances you don't do that. It is also obvious you get exactly one chance. There are also missile flight issues. The launch direction may require rapid missile maneuvers very near the ground to happen at rates the missile simply can't do. It is imperative the missile crew and the support staff be aware that a missile may be launched "unexpectedly" :-). Ideally, you want a SHORAD system allocated to defend the S400.

All that said, when the Ukrainians initially received the Patriot systems they apparently did leave it full automatic lots of the time. It worked well. I doubt the S400 would do the same.

Can an AWACS type aircraft pick up those low flying weapons easily?  Even if they do, how do they facilitate the destruction of those weapons.  Can an AWACS system overide the control of the ground based air defense systems and launch the air defense systems long before the Air defense system radar even finds it?

Yes, an AWACS system can detect such targets almost immediately after they are launched. The AWACS would evaluate the threat and ideally assign an aircraft to shoot it down. The AWACS can track "lots" of such target and coordinate the air battle to (in theory) make the best use of its assigned air assets. The aircraft get a vector (and updated vectors if needed) toward the target. Once the aircraft has the target on its radar, the AWACS quits helping. The aircraft then shoots the missile down. Obviously this engagement can't take forever. It depends on where the missile is coming from. If no aircraft is available with permissive geometry, the AWACS can designate the target for any appropriate missile battery. The NASAMS has often been demonstrated operating in this mode. The AWACS doesn't exactly "take control". The battery computer and guidance uplink participates (as can the battery personnel). However, if the battery has not detected the target the AWACS updates will be used to "steer" the AMRAAM to the target until it is within range. Patriot can be used the same way. Additionally, Patriot batteries can "handoff" targets to NASAMS. In this manner, batteries can engage targets they themselves cannot "see". All this has been demonstrated. The AWACS has clearly demonstrated in actual conflicts the ability to shoot down cruse missiles at scale using aircraft directed by the AWACS. The "other" capabilities have definitely been demonstrated many times, although AFAIK it hasn't been used in conflict.

Russia claims the A-50 can do all these same things as part of their IADS. However, we have not seen them actually do this. Russia also claims they can guide the long range S400 missiles from the A-50. This is a very "big deal" in long range engagements. However, AFAIK we have never actually seen the Russians do any of this, even in drills.

This conflict has created a really new issue the worlds militaries need to deal with.  We are no longer talking about expensive Reaper drones firing a few weapons at a target, but more about flying hundreds of cheap drones carrying from 5 to say 50 kilos of explosives. I think it would be very hard for a single country to be able to stop this kind of attack outside of the largest countries on the planetl

I am not in complete agreement. The hundreds of cheap "quadcoptor" drones have very limited range. These aren't weapons that have much reach. They are important weapons and certainly will make a tactical contribution in the near future. Most of these drones are not fast. The ones that have reasonable range are more like the  Shahed 136. They are slow and can easily be run down by high performance aircraft. None of these weapons are gamechangers. There is going to be a lot of development of these weapons making them more capable. There will even more improvements in defensive measures IMO. Even in the last two years massive changes have occurred during the middle of a war. Five years from now, the scene will be vastly different than it is today. IMO FPV drones will basically not exist in five years, if not sooner. Their EW signature can't be eliminated. If you radiate and can't defend yourself you will be a big bullseye. Scarily, AI will be used to recognize and attack targets with maybe a "squirt" when that determination is made. In short the future will not look like the present and the correlation of forces will be very different.

[Goose]

What I do not understand at all is how effective Mainstay, or AWACS aircrafts are at picking up incoming missles, aircraft, or whatever, flying low in the weeds so to speak.

The short answer is very effective, subject to certain assumptions. I don't know the exact detailed capability of an A-50, but even assuming it is comparable to a late 1990s AWACS, it has a very good Digital Moving Target processor that uses the coherent Doppler shift in the radar returns from moving targets to make them absolutely stand out from the ground clutter. These platforms can even see cars on the freeway if they turn the low speed limit down far enough. The assumptions are 1) the target has a relative velocity component in it's course that is large enough to be detected, and 2) the target has a radar cross section large enough to be detected. The second requirement can be greatly affected by building a "stealth" cruse missile, which both we and the Russians (e.g. KH-101) have done. However, the physical size of most cruise missiles is such that the X band radar will see a missile when it would not see an aircraft of similar stealth. It has to do with the mode of reflection involved. That is one reason (of many) why the  E-7 Wedgetail operating in L band is such a high priority acquisition for the USAF. The USN was very smart (or lucky) in the original design of the E-2. Its radars, including APS-145 (https://www.radartutorial.eu/19.kartei/0...86.en.html) and the latest and greatest APY-9 (https://www.radartutorial.eu/19.kartei/0...83.en.html) operate just below P band.

BI recently had an article how we are now giving Ukraine a long range cruise missle that  has a range of 200 miles.  I am not sure how the Tomahawk missles feels about that.  200 miles is hardly a long range weapon.

The Tomahawk engine will just be warmed up at 200 miles :-).

I have seen articles that indicated that the S400 can find things flying down in the weeds, say  100 to 200 ft above mean ground level about 45 km out.  Can it then intercept that incoming missles in the time left if the incoming weapon is say moving at 500 mph?  Seems to me there is a very good chance that the incoming weapon would hit you before you hit it.

45 km is not literally correct. The radar horizon (without refraction) for a radar antenna located 10 feet above the ground and a cruise missile at 200 ft is 34.1 km. If the radar is at 20 ft in the air the horizon is 36.7 km. At 926 kph the 36.7 km will be covered in 142.7 seconds. Obviously the intercept needs to occur well away from the S400 to avoid fragment damage. Can an S400 accomplish this? The answer is a very qualified yes. The S400 does have an "automatic" mode that could in theory launch the missile. How well that actually works is an open question. The Russians tend to prefer a "man in the loop" operation. It is also pretty risky leaving a missile battery in full automatic mode for a long period of time. It is probable there is a non-zero false alarm rate. There are "red on red" issues at the very least, especially because supposedly both Russia and Ukraine aren't using the IFF much if at all. Under normal circumstances you don't do that. It is also obvious you get exactly one chance. There are also missile flight issues. The launch direction may require rapid missile maneuvers very near the ground to happen at rates the missile simply can't do. It is imperative the missile crew and the support staff be aware that a missile may be launched "unexpectedly" :-). Ideally, you want a SHORAD system allocated to defend the S400.

All that said, when the Ukrainians initially received the Patriot systems they apparently did leave it full automatic lots of the time. It worked well. I doubt the S400 would do the same.

Can an AWACS type aircraft pick up those low flying weapons easily?  Even if they do, how do they facilitate the destruction of those weapons.  Can an AWACS system overide the control of the ground based air defense systems and launch the air defense systems long before the Air defense system radar even finds it?

Yes, an AWACS system can detect such targets almost immediately after they are launched. The AWACS would evaluate the threat and ideally assign an aircraft to shoot it down. The AWACS can track "lots" of such target and coordinate the air battle to (in theory) make the best use of its assigned air assets. The aircraft get a vector (and updated vectors if needed) toward the target. Once the aircraft has the target on its radar, the AWACS quits helping. The aircraft then shoots the missile down. Obviously this engagement can't take forever. It depends on where the missile is coming from. If no aircraft is available with permissive geometry, the AWACS can designate the target for any appropriate missile battery. The NASAMS has often been demonstrated operating in this mode. The AWACS doesn't exactly "take control". The battery computer and guidance uplink participates (as can the battery personnel). However, if the battery has not detected the target the AWACS updates will be used to "steer" the AMRAAM to the target until it is within range. Patriot can be used the same way. Additionally, Patriot batteries can "handoff" targets to NASAMS. In this manner, batteries can engage targets they themselves cannot "see". All this has been demonstrated. The AWACS has clearly demonstrated in actual conflicts the ability to shoot down cruse missiles at scale using aircraft directed by the AWACS. The "other" capabilities have definitely been demonstrated many times, although AFAIK it hasn't been used in conflict.

Russia claims the A-50 can do all these same things as part of their IADS. However, we have not seen them actually do this. Russia also claims they can guide the long range S400 missiles from the A-50. This is a very "big deal" in long range engagements. However, AFAIK we have never actually seen the Russians do any of this, even in drills.

This conflict has created a really new issue the worlds militaries need to deal with.  We are no longer talking about expensive Reaper drones firing a few weapons at a target, but more about flying hundreds of cheap drones carrying from 5 to say 50 kilos of explosives. I think it would be very hard for a single country to be able to stop this kind of attack outside of the largest countries on the planetl

I am not in complete agreement. The hundreds of cheap "quadcoptor" drones have very limited range. These aren't weapons that have much reach. They are important weapons and certainly will make a tactical contribution in the near future. Most of these drones are not fast. The ones that have reasonable range are more like the  Shahed 136. They are slow and can easily be run down by high performance aircraft. None of these weapons are gamechangers. There is going to be a lot of development of these weapons making them more capable. There will even more improvements in defensive measures IMO. Even in the last two years massive changes have occurred during the middle of a war. Five years from now, the scene will be vastly different than it is today. IMO FPV drones will basically not exist in five years, if not sooner. Their EW signature can't be eliminated. If you radiate and can't defend yourself you will be a big bullseye. Scarily, AI will be used to recognize and attack targets with maybe a "squirt" when that determination is made. In short the future will not look like the present and the correlation of forces will be very different.