Combat: What Is "Radar Notching"? And How Do You Do It? | DCS WORLD

0:57 What Is Notching?
2:42 Kinematic Effects Of Notching/Beaming
3:36 How A Pulse Doppler Radar Notch Works
5:29 Looking At Different Scenarios
8:55 Additional Concepts
15:33 Examples In DCS
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#GRTutorial #DCSTutorial #AirToAirCombat #GR #DCSWorld #RadarNotching

[@philhines]

Hey mum, Today in Fighter Pilot school, I learned about radar notching! 😁😁😁

[@reccecs4]

Wow. The precision required to collide two aircraft at that closure rate is frankly very impressive. That’s a small target in a big sky.

[@darthioan]

For the sake of accuracy, it is not really a collision. It is an interception (with the warhead detonating once it reaches within a certain area in the proximity of the intercepted aircraft). Precision is achieved through mathematical equations. Electromagnetic waves allow for it. The method is inherently precise, otherwise radio technology (we use nowadays in our phones in order to communicate complex data in order to watch videos on youtube on our phones, or track our location with an error rate than can be measured in inches) would not have existed.

[@reccecs4]

@@darthioan @16:42

[@LeCharles07]

"The missile knows where it is at all times; it knows this because it knows where it isn't. By subtracting where it is from where it isn't, or where it isn't from where it is, (whichever is greater) it obtains a difference or a deviation. The guidance subsystem uses deviations to generate corrective commands to drive the missile from a position where it is to where it isn't and arriving at a position where it wasn't it now is. Consequently, the position where it is now the position that it wasn't, and it follows that the position that is was is the position that it isn't. In the event that the position that it is in is not the position that it wasn't, the system has acquired a variation; the variation being the difference between where the missile is and where it wasn't. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the missile must also know where it was. The missile guidance computer scenario works as follows: because a variation has modified some of the information the missile has obtained, it is not sure just where it is. However, it is sure where it isn't (within reason) and it knows where it was. It now subtracts where it should be from where it wasn't (or vice-versa) and by differentiating this from the algebraic sum of where it shouldn't be and where it was, it is able to obtain the deviation and it's variation which is called 'error'."

[@AxiomIndustries]

"In a five to ten minute video"

[@DCSChopsticks]

To be fair the basic explanation was 9 mins so...

[@slowhornet4802]

DCS F-14 MLC switch in AUTO mode turns MLC filter off if radar looks up 3+ degrees above the horizon. MLC speed range is +/- 133 knots of the F-14's ground speed (= if target generates a doppler shift within that range the radar believes target is stationary and is considered as "ground return" in a look-down scenario). in a look-up scenario if the target has a ground speed close to the F-14's and if it is flying away from the F-14 the doppler shift is close to zero and not high enough to detect the target. That speed range is +/- 200 knots Some time ago I read that US F-15 pilots based in Germany were surprised because their radars detected cars on German highways. Apparently the cars were fast enough to leave the MLC filter range. I guess the F-15s were following the path of the autobahn and no matter if cars were driving in same or in opposite direction the relative difference of speed compared to ground return speed was usually not enough to detect them. And then a Porsche showed off....

[@AshleyGamerGirl12]

Thanks for the videos! This one was extremely informative!

[@grimreapers]

thx

[@ndestr0yr]

Quick correction, if the wavelength of the light is reduced (or frequency increased) it should appear more "blue."

[@slowhornet4802]

How to beat the F-14 in a Harrier (1 vs 1 AI): F-14 (excellent AI) at 20,000 ft over open sea at 400 knots. F-14 has 4 AIM-54 C, 2 sparrows and 2 AIM-9 Harrier (player) flying at 16,000 ft southwards directly towards the F-14. F-14 will pick-up Harrier at around 62 miles. If Harrier goes very low and fast F-14 will shoot Aim-54 when about 22 miles away. But: if Harrier slows down to 80-90 knots F-14 will not shoot (or in case the F-14 shot an AIM-54 when Harrier was faster than about 150 knots) it will not hit. Harrier can shoot AIM-9 at F-14 . I assume that the Harrier is "notching without beaming" (MLC filter is 266 knots wide around the F-14's ground speed) Would be great to test with human pilots in F-14 and Harrier. Btw: F-16's radar was also beaten.

[@BjornTheDim]

I realize that this is an old video, but wanted to say thanks for distilling a complicated topic in DCS to something that is almost intuitive and understandable in principle.

[@BryanDenham]

thank you for the help Cap this was an eye opener for me.

[@184Kitkat]

Great stuff! Well explained. 👌

[@masonreppeto882]

Thanks a lot man. I didn't realize that it differentiates targets by their incoming velocity .

[@Stranglewood]

Great explanation - thank you!

[@Eduard_Kolesnikov]

Thank you for well explained information. It helps me to understand that.

[@patrickt2746]

Phenomenal explanation and demonstration

[@breakz187]

Love this guys series of videos

[@user-NavalAviator]

Very helpful information Thanks 👍

[@michaelfriscia8166]

a simple way to understand notching from a visual perspective is if you've ever been driving down the road and seen a aircraft coming in for a landing, if it's angle and speed relative to your view angle is correct it will appear to be hovering. if all you could see was movement with this perspective there would be no movement hence it appears to hover if your eyeball was a radar it would simply lose sight of the aircraft at this point and therefore could not lock it or Target it until your view angle was outside the background noise parameters and then could be differentiated visually it would appear as the aircraft was once again moving very slowly at first as it exits the notch and then of course you would notice it moving faster and faster.

[@manatoa1]

Thanks, very clear explanation

[@Senior-Busa-Rider]

Very informative thank you 🦅🇺🇸🦅

[@Lemmes098]

Great video! I finally somewhat grasp the concept now. Maybe a stupid question (especially on an older vid) but how come the issue of ground clutter for the enemies radar isn't significantly reduced when fighting over an ocean as in your example fights?

[@P90F55]

Brilliant!

[@qc_ploum-zoum2]

Thanks, your the best

[@3dmax911]

great lesson !! thanks a lot

[@SubParPilot]

This is ridiculous that I'm here as an actual apache pilot in real life to get a better understanding of radar haha

[@darthioan]

Aren't you required to pass tests which demonstrate a certain level of physics knowledge in order to qualify? That's crazy.

[@us_taz9444]

Ya Finally i found channel explain about air jet fighter radar. Friday 9 April 2021 11:17 PM.

[@svastanesto4518]

Thanks a very helpful video. I had a lot of problems recently with AIM54.

[@slowhornet4802]

Hitting with them or avoiding being hit?

[@svastanesto4518]

@@slowhornet4802 Avoiding being hit😊

[@tony9146]

@@svastanesto4518why are you getting so close that they’re hitting you with AIM-54s? Chances are you’re a sitting duck up close in each of those cases and there’s not much you can do other than try and improve your tactics for future engagements.

[@andreartymiuk]

Need to be aware of the distinction between the firing fighter's radar and the onboard missile radar for an Active FOX3. Once the missile has switched to its onboard Pulse Doppler active radar and is no longer being fed its guidance commands from the Host fighter you have to notch taking into account the CURVING PATH of the missile. So you may be notching the host plane's radar as in the 2nd example, but the actual missile's own radar is coming from a different direction as its flight curves and its bearing to you changes. So you have to fly a curve to keep notching the MISSILE's radar especially if, like with a Aim54, the radar attempts to reacquire if it loses lock. Doing that then makes you visible to the host fighter for a follow up shot since you are not then notching his radar! Note this assumes that as for a Aim 120 or an Aim 54 that the missile receives its guidance from the Host fighter until it goes active and the missile is not itself receiving and guiding on the radar reflection of the Hosts radar from the target.

[@frederf3227]

AIM-120 blends in updates from the host guidance even after going active and getting autonomous track. While missiles can displace from the firing platform-target LOS, they don't normally curve but instead fly straight line to intercept

[@andreartymiuk]

@@frederf3227 Interesting, wasn't aware of that. Presumably only applies if host retains its track on the target after pitbull. Learn something every day! But the target was manoeuvring it couldn't follow a straight route, it would have to curve to follow the target, or else it would miss surely? They certainly do that in DCS.

[@andreartymiuk]

CAP .. looks like something else to test here?

[@slowhornet4802]

Question for the GR team: Can you "notch without beaming"? (Edit: see my earlier post) F-14 MLC filter is +/- 133 knots around F-14's ground speed. If an opposing jet flies lower than the F-14 and if the opposing jet flies slow enough (around 100 knots or less) it should be possible to "notch" the F-14 even without beaming. So for example a Harrier could fly with slow ground speed directly towards the F-14 and should not be detected. I mean the whole thing about beaming is to have the doppler shift of your aircraft in the same range as the ground return doppler shift. If you want to fly fast (to keep high energy state) you need to beam in order to fool the doppler radar. But if you decide to go slow enough you could fly directly towards the F-14 and the radar would still consider you as "ground". E.g. F-14 flying with 500 knots. Ground returns have a closure rate of 500 knots, the Harrier would have a closure rate of 600 knots (if flying 100 knots GS directly towards the F-14).

[@grimreapers]

Absolutely. If you fly in front of a guy in the same direction, at normal detection range, and match his speed exactly. His PD radar can not see you!!

[@slowhornet4802]

@@grimreapers Thanks for your reply. Yes, that would be the "zero doppler shift" effect (no closure / separation speed, no doppler shift, no detection) Per the manual it should be even sufficient to stay within plus / minus 100 knots of the F-14's speed. But I meant also the following scenario: F-14 flies at 20,000 feet, 500 knots ground speed, Harrier flies directly towards the F-14, but Harrier flies at very low level. Scenario 1): Harrier flies fast (300+ knots). Expected result: Harrier will be detected because the Harrier is clearly faster closing to the F-14 than the ground. Scenario 2): Harrier flies slow (100 knots or less). Expected result: Harrier should not be detected by PD radar. Reason: F-14's radar is filtering out ground returns based on the F-14's ground speed plus/minus 133 knots (per DCS F-14 manual). Basically, the F-14 radar thinks: I am moving with 500 knots. If a radar return is closing at 500 knots (which is detected by the doppler shift), the target is stationary (aka "ground"). If something is way faster closing or moving away it must be something other than "ground". Way faster means: more than 133 knots difference compared to ground closure. If the radar return closes at 800 knots (scenario 1) the radar classifies this return as "target" / not ground / not stationary. Now the F-14 radar seems to have a relative wide range (plus minus 133 knots relative to its ground speed) where radar returns would be classified as "stationary" compared to the F-14. That's why I thought a low and slow flying aircraft could be fly directly towards the F-14 without being detected. Harrier would generate doppler shift, but the doppler shift would be close enough to the ground doppler shift and therefore filtered out (scenario 2). So that would be "notching without beaming". Basically, the easiest way to fool the radar is still beaming (because ground and Harrier are closing the F-14 at the same speed and thus having the same doppler shift. But if you are slow enough the F-14 would still not detect you even if you not beam at all but fly straight towards the F-14, just fly slow enough. That is at least the theory. Sorry for the long reply. Explaining complex things and flying DCS are not my core strengths.

[@MrKKUT1984]

Inverse square law is why the return is stronger up closer and weaker further away

[@NZ.YouTube]

What setup is he using for the head tracking? It looks amazing!

[@mdansson]

Hey, pretty new follower of your channel and love your work. Thanks for doing all this. I don't even have DCS yet, but I'll get to it when I can. In the off-chance that you read this message, I have a question/request: Maybe this has already been addressed, but I would like your input on the gaming setup you personally use (or link me, if it's already somewhere and I just haven't found it), and any advice for the modern state of VR and how to get the best experience... i.e. what computer specs needed, what minimal VR resolution works great for DCS, etc. Of course budget is an issue, so breaking it down into some "tiers" from budget to no-costs-spared would be great. My concern is getting into DCS with a VR setup and being less than thrilled, bc the resolution is so high in your videos, but I know in the VR headset the resolution is not as high.

[@AdamLindgrenComposer]

Hi madansson, The best place to get this info is the [GR] public Discord server linked in the description, but I'll give you a rundown of some options. Generally, you should not run DCS at higher than 1080p, as targets get very hard to spot at higher resolutions. This is not just a preference thing; it impacts your targeting (especially A2A). That being said, many people do fly at higher resolutions, but the competitive players generally fly 1080p or lower, even. Your three most important components for good DCS flying IN ORDER: GPU, RAM, Storage Device. CPU is less important, but keep in mind that DCS is a single-threaded workload (though hopefully that will change within the next year). Minimum specs to assure DCS gets running decent in single player: DCS Stable Version i5 6th gen (2016) 16 GBs RAM GTX 970 (or AMD equivalent) Stored on HD/Hybrid Drive Medium Specs for a trouble-free experience, and to fly multiplayer in large servers (as seen in these video, like [GR] servers): DCS Beta Version i5 7th gen (2017) 24 GBs RAM GTX 1060 (or AMD equivalent) Stored on SSD Good specs for idealic DCS experience: DCS Beta Version i7 7th gen (2017) 32 GBs RAM GTX 1080 (or AMD equivalent) Stored on NvME.SSD Decent build for VR: i7 7th gen (2017) 32 GBs RAM GTX 1080ti Stored on NvME.SSD Oculus Rift or Rift S Ideal build for VR: i9 9th or 10th gen (2019) 32 GBs of RAM RTX 2080ti Stored on NvME.SSD HP Reverb (revision 1)

[@passantNL]

kzbin.info/www/bejne/p36phHaQfKyEa80

[@mdansson]

@@AdamLindgrenComposer That's really great info, thank you. I'll have to take some time to look over it and budget out these options. Not to mention, the VR setup would also prompt me to get a stick and throttle and probably rudder pedals, for the whole experience, tho rudder pedals wouldn't be urgent if there is a short-term way to control rudders with hands on stick and throttle. Just to clarify, 1080p is the recommended top resolution for VR, even though in VR, the view is pixelated, screen door effect, etc? I've heard about this easier-to-spot-planes with the larger pixels of lower resolution, but I also know that it is pixelated, since even in HD, you're looking at 1080p covering, say, 130 degrees of view, as compared to a computer screen. But if 1080p is recommended, then it seems the tech is already here. For real-world like precision, I think we need something like 8k resolution which, well, not only is making a VR headset difficult, but the required processing power goes bonkers with that many pixels to drive. Anyway, thanks again, I have what I need to work with for now. Cheers!

[@theduckcrispy6596]

Fighter pilots nowadays learned 40% of their Air combat knowledge mostly from DCS 😂😂😂

[@krzysztofgawe1089]

Sorry to trouble you sir, but 11:15 "Range is proportional to power" . Well... no it isn't. Power of the signal RETURNING to radar is proportional so range square. Means: when you double the range , power of the signal returning is 4x smaller. Everything except it is just brilliant. Thank u for your time and effort.

[@falconred2614]

What about AN/APG-63 and AN/APG-70？ Could these radar defeat notching?

[@grimreapers]

Great Question, honestly no idea...

[@LupusAries]

Yeah but the RIO is still superior to the computer......at least according to the Tomcat Pilots.😉 And that's due to him being able to use more unsual techniques, while the computer just works programs that are always similar. So a Rio is harder to beat, If he's good. He's also good at overcoming jamming. So I wouldn't agree that he's really redundant, after all a significant portion of the Super Hornet and the french AdA Rafale Force are double seaters. And Like in the Cat they do more than Just operate the Radar. Their presence also helps with crew Taske saturation, in Essence a two man crew can stave off of mental overload due to Task saturation.

[@philhines]

Sure thing. Perhaps the other side of it though could be that if you have a single-seat pilot he can throw the ship around harder without worrying about GLOCing his Rio! 😅 Or making him puke lol! ;)

[@linusa2996]

@@philhines All the pilot needs to do to avoid GLOCing the RIO is to call out "G's" before he/she pulls. This tells the RIO to get ready. It's a matter of crew training and co-ordination.

[@candle_eatist]

So just stay low when notching

[@Slikx666]

Well that makes sense. 😀 Before it was a thing. 😋

[@trentvlak]

How is it possible such a simple thing works? The radar return from the ground is going to be much slower.

[@bigbrotheriswatching1190]

>Hear about radar notching from Habitual Linecrosser >Look it up >Leave after watching this video to play war thunder

[@PerOlofForsman]

Cap! I was thinking they use MTI? In Viggen you have PPI and B-scope! What is B-scope?

[@grimreapers]

B scope is what you get F-15, where it stretches the display from angled to Square.

[@PerOlofForsman]

@@grimreapers thank you and have a good day

[@SUP_Bigans]

Thanks for this video! A question: is possible in tws tracking a plane flying perpendicular or notching (in the low right part of mfd) as at 03:22 of this video kzbin.info/www/bejne/gYCXpZ-nZ92UbNE

[@grimreapers]

will look when I can

[@projenitor2387]

I wish over G actually caused damage...

[@projenitor2387]

@@stingerrgb2754 Youd figure with an FCS it would prevent that.

[@mtuers]

So this probably sounds stupid and maybe I wasn't paying attention... if you're notching a radar, won't the other aircraft disappear from your radar as well?

[@PaletoB]

So a helicopter should bee really hard to detect?

[@Citizen_Snips1]

Well yes but actually no, but those big rotating blades give quite a large RCS.

[@lkfhjto]

The rotor is moving, it makes it visible, but a heli can easily mask in terrains.

[@grimreapers]

Helos are a whole different kettle of fish...

[@fremenGaming]

If i understand physics of this correctly (did study Physics, and I am also gamedev - not related but can help understanding how stuff can be solved) it is not exactly true how notching should work. In order to have "true notching" you would have to move more in specific pattern, because you need to maintain the same "velocity change" as the ground to the offender :P. But I am not sure i would need to make an simulation :P But true, if target is far, the angle is changing slowly which means that you don't have to be so precise, that is probably also why when you are closer it is easier to notch because of fast change of angle to target

[@patricktho6546]

14:30 this you can see very well in War Thunder.

[@branchprediction9923]

can a helicopter notch? or will the rotors give it away?

[@frederf3227]

Rotors

[@slowhornet4802]

Rotors. But GR put up a video how to go into stealth mode in the Huey. Just search for mast bumping.

[@branchprediction9923]

@@slowhornet4802 sooo ur telling me to blow off my rotors? this guy!

[@richardhockey8442]

@@slowhornet4802 And also in a wide range of other helicopters - see 'crashing into the ground'

[@iltgdellosportivo2066]

I thought than u cant notch a near plane because your relative speed is very highi

[@r.d.w2437]

Il Tg dello Sportivo it’s not about your relative speed per se. it’s about how your relative speed with the bandit is similar to your relative speed with the background.

[@iltgdellosportivo2066]

@@r.d.w2437 ..... if the plane is above you not. And the relative speed with the background is still called relative speed

[@r.d.w2437]

But the “notch” is a rejection feature of the radar. It ignores a small range of relative velocities that are basically equal to your ownship speed so targets that have the same relative velocity as the ground will also be rejected. Hence flying perpendicular to the radar source, be it airplane or active missile. It is how look down shoot down radar was implemented. Depending on the aircraft software you sometimes could get a reduced notch filter in a look up situation. This is just for pulse Doppler type Radar.

[@iltgdellosportivo2066]

@@r.d.w2437 are u stupid?

[@evolgenius1150]

ok so use tews to see if ur abeam.. nice.

[@simmo2327]

Poop? First

[@BaasB007]

borrrrrrrrrrrrrrrrrrrrrrring

[@Zayats_MW]

Bro shut the fuck up

[@fady904]

You talk too much. Cut to the chase....