SwingKid Posted February 24, 2005 Share Posted February 24, 2005 SK, You didn't mention TWS on page 4 ... What is TWS, other than the antenna "swinging from side to side" and "up and down"? Now the lock breaks, the antenna starts scanning left to right in search mode ... at this some point during the sweep of the ant, the target is not at 90 to the beam and would simply reacquire. Are you able to post images? Can you please provide two sketches showing the angle between the beam and the target that you are describing, one that is and one that is not 90 degrees, with the target pointing in the same direction and only the radar beam "swinging around"? I'll use it as a reference in my explanation. -SK Link to comment Share on other sites More sharing options...
Kula66 Posted February 24, 2005 Share Posted February 24, 2005 SK, do you have a good URL for this ?? Thanks, James Link to comment Share on other sites More sharing options...
SwingKid Posted February 24, 2005 Share Posted February 24, 2005 SK, do you have a good URL for this ?? No, sorry. We had a discussion about it on the UbiSoft forum a long time ago, with diagrams and everything, but running a search, I am unable to find any trace of it. Looks like it was deleted. Too bad, there were a lot of pretty good discussions there, but that's the internet for you. Everything you need gets deleted, every silly flame you wish you never wrote gets enshrined for all eternity. :roll: I'm afraid I can't explain it much better than I already have without diagrams, and I'm a little too busy to do that all over again right now. Maybe if you illustrate what you're thinking of I can point something out, but after how long it took to debate this same topic the last time, this time I'm going to insist that somebody else does most of the graphical work. :wink: -SK Link to comment Share on other sites More sharing options...
Kula66 Posted February 24, 2005 Share Posted February 24, 2005 Not to worry ... I'll do some digging, see what I can find. James Link to comment Share on other sites More sharing options...
GGTharos Posted February 24, 2005 Author Share Posted February 24, 2005 Kula, as long as you stay close to perpendicular (you can be a degree or two off) to the threat, you won't show up n radar. That the beam sweeps doesn't mean anything - it's pretty narrow and when it's actually 'looking' at you you've got the exact same situation as if you were locked onto. If you continue flying your present course you WILL eventually show up no radar since you won't stay perpendicular for ever this way, but if you continue beaming you won't show up on search. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
GGTharos Posted February 24, 2005 Author Share Posted February 24, 2005 Kula, as long as you stay close to perpendicular (you can be a degree or two off) to the threat, you won't show up n radar. That the beam sweeps doesn't mean anything - it's pretty narrow and when it's actually 'looking' at you you've got the exact same situation as if you were locked onto. If you continue flying your present course you WILL eventually show up no radar since you won't stay perpendicular for ever this way, but if you continue beaming you won't show up on search. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
gherring Posted February 25, 2005 Share Posted February 25, 2005 If I am flying an F-15 due north, and get locked by a Sue that is dead ahead, flying south. I can break the lock by turning east. This puts the Sue at 9 oclock on my TEWS. If I continue east, the Sue (assuming it remains north of the original lock point and keeps flying south) will drift to 8 oclock on the TEWS. I will reappear on the Sue's radar long before I fly out of its scan zone. But if I gradually turn so that the Sue remains at 9 oclock, I will eventually fly out of the scan cone at a course of 60 degrees (assuming the Sue keeps scanning straight ahead) and not reappear. Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 Bingo, thank you. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 If I am flying an F-15 due north, and get locked by a Sue that is dead ahead, flying south. I can break the lock by turning east. This puts the Sue at 9 oclock on my TEWS. If I continue east, the Sue (assuming it remains north of the original lock point and keeps flying south) will drift to 8 oclock on the TEWS. I will reappear on the Sue's radar long before I fly out of its scan zone. But if I gradually turn so that the Sue remains at 9 oclock, I will eventually fly out of the scan cone at a course of 60 degrees (assuming the Sue keeps scanning straight ahead) and not reappear. :shock: Just a moment.... But if I gradually turn so that the Sue remains at 9 oclock, I will eventually fly out of the scan cone at a course of 60 degrees This cant be correct look to the picture: why the enemy should not GET the BLUE contact in the radar ?? The Blue hava a greater closure speedy to the Red And the Green have a lower closure speedy I mean near to Zero should the radar of the Red someway try to FILTER the green ?? I always think the beaming consist in get MY closure speedy to the Enemy as near as ´possible to zero .....so the enemy radar will try to FILTER me thinking im a STATIC object...im Wrong ?? Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 Yes, your closure to the enemy cmpared to the closure of the ground along tthe beam. The vector of the ground closure is always along the beam, at least that's what I think SK is saying. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 Yes, your closure to the enemy cmpared to the closure of the ground along tthe beam. The vector of the ground closure is always along the beam, at least that's what I think SK is saying. Hey GG i think this reply is HARD even in Portuguese 8) ...but i will try figure out what you mean :P btw SK i will really apreciate your graphic explanation if you can find it it can make things more clear :D Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 basically, you want your colosure to be the same as the ground. That puts you in the notch. But when your beam is looking to the side, it is measure ground speed in that direction, not straight ahead of the aircraf,t there fore to notch you must be perpendicular to the beam. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 basically, you want your colosure to be the same as the ground. That puts you in the notch. But when your beam is looking to the side, it is measure ground speed in that direction, not straight ahead of the aircraf,t there fore to notch you must be perpendicular to the beam. Got it 8) Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 basically, you want your colosure to be the same as the ground. That puts you in the notch. But when your beam is looking to the side, it is measure ground speed in that direction, not straight ahead of the aircraf,t there fore to notch you must be perpendicular to the beam. This sould Work to Missile Radar Beam ?? because i think it is not modeled this way in lock on Should be more easy to notch the internarl radar of the missile.... because it dont have enougth power rigth ? Btw...if i make a manouver to avoid my target put his 9 or 3 oclock can i sustain the lock ?? I mean my target will try notch me....he will try keep turning.....so if i try compenste his turn it will still on radar ? Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 Actually it's probably harder because missiles will use special trajectories to prevent you from doing just that - they also move so quickly that staying in the notch gets exceedingly difficult. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 Actually it's probably harder because missiles will use special trajectories to prevent you from doing just that - they also move so quickly that staying in the notch gets exceedingly difficult. Another one... If im at 8k the and my target is also at 8k i firet on him then dive to 5k there is no way he can notch me rigth ? Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 Technically, there's no reason why the radar can't ignore the notch gate at that point, I think, depending on the design ... some are mroe flexible, some less ... in LOMAC, you cannot be notched when below your target, but aspect changes at long range -can- cause a loss of lock. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
zzzspace Posted February 25, 2005 Share Posted February 25, 2005 Actually it's probably harder because missiles will use special trajectories to prevent you from doing just that - they also move so quickly that staying in the notch gets exceedingly difficult. Yes, thank you GGT, that's precisely what I was referring to when I said it was practically impossible to fly it, one may manage it for a moment, but I don't think (yes, this is an OPINION ... for those who can't tell the difference) the situational awareness and correct timing will be available to fly it consistently. Perhaps an advanced autopilot married to direct passive sensors could fly it consistently (and perhaps the F-35 advanced auto-pilot may be able to fly it routinely to maximise survivability) but I seriously doubt a human pilot can do it very consistently, or consistently enough to utilise it. However, they will beam anyway for other energy sapping, FOV and tactical maneuver reasons, and this may (yes, NOTE, this is also an OPINION) also allow ECM to become more effective in conjunction with the beaming. aspect ||| Romanes eunt domus ||| zzzspace V2.0 REAL SOUND for DCS World - and all Modules ||| Link to comment Share on other sites More sharing options...
GGTharos Posted February 25, 2005 Author Share Posted February 25, 2005 I think you can consistently -and- usefully notch an aircraft or missile radar at distance (please note that I refer to ARH missiles). There's a lot of ifs and buts and why's in there, and I'll be glad to speculate and discuss sometime tomorrow. The short of it is, I agree with you in some situations, I disagree in others (particularely long range or where there might be a significan altitude difference that may cause the targeted aircraft to fly out of the scan zone in short order after notching) Gotta run to bed now :) [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
zzzspace Posted February 25, 2005 Share Posted February 25, 2005 I think you can consistently -and- usefully notch an aircraft or missile radar at distance (please note that I refer to ARH missiles). There's a lot of ifs and buts and why's in there, and I'll be glad to speculate and discuss sometime tomorrow. The short of it is, I agree with you in some situations, I disagree in others (particularely long range or where there might be a significan altitude difference that may cause the targeted aircraft to fly out of the scan zone in short order after notching) Gotta run to bed now :) Well, good night, and I agree, at longer range it is going to be much easier to maintain a Doppler notch geometry. ||| Romanes eunt domus ||| zzzspace V2.0 REAL SOUND for DCS World - and all Modules ||| Link to comment Share on other sites More sharing options...
SwingKid Posted February 25, 2005 Share Posted February 25, 2005 btw SK i will really apreciate your graphic explanation if you can find it it can make things more clear :D Ok I think I found the images, let's see if this works. As the fighter moves forward, the ground in front appears to be approaching, the ground behind appears to be receding, and the ground to the sides appears to be neither approaching, nor receding. So, even though all of the ground is "moving" together and in the same direction (black arrows), the amount of closure that is seen by the radar (dark green arrows) depends on the direction the beam is steered (bright green lines): Depending on the length of the green arrow, and its direction toward or away from the radar, we can separate the ground clutter into "zones". The ground clutter in front of the fighter will have high Doppler frequency shift (light blue), and the ground in other directions will have lower Doppler frequency shift (darker blue): So, as the fighter changes direction, the colored disc turns with it, as if it is somehow "attached". This disc provides the ground clutter background on top of which the targets must be detected: Now, what happens when a beaming target is directly ahead of the radar? Consider (a) below. The target motion is horizontal (violet arrow), but it also appears to be approaching the radar, because the radar is moving forward (black arrow). The closure component of the target is the same as the closure component of the surrounding ground clutter (green arrows). So, we have a "bright blue" target on a "bright blue" background - invisible: What happens if the illuminating fighter turns, to put the target at 1 or 2 o'oclock? Then we have situation (b) above. Yes, the closure of the target is different than it was before, as seen by the shortened green arrows - the fighter has changed color from light blue to dark blue - but the closure of the surrounding ground clutter is reduced by the exact same amount. By turning to put the target at 2 o'clock, we moved it into a darker part of the ground clutter disc. So, now we have a dark blue target on a dark blue background - still invisible. So, because the ground clutter environment is caused by the illuminating fighter's own motion (black arrows), all the target has to do is fly a course that keeps the enemy radar at 3 or 9 o'clock, and it will be "beamed", regardless what direction the illuminating fighter turns. Hope this helps, -SK Link to comment Share on other sites More sharing options...
wsoul2k Posted February 25, 2005 Share Posted February 25, 2005 Yes...tks a lot SK...this make the things more clear :D Rodrigo Monteiro LOCKON 1.12 AMD 3.8 X2 64 2G DDR ATI X1800XT 512 SAITEK X-36 AND VERY SOON TRACKIR-4 Link to comment Share on other sites More sharing options...
Kula66 Posted February 25, 2005 Share Posted February 25, 2005 Thanks SK ... this is a great help. James Link to comment Share on other sites More sharing options...
Skywall23 Posted February 26, 2005 Share Posted February 26, 2005 O Pk (probabilidade de acerto) é estimado em 70% contra caças. Thats portuguese. Ill translate: The KP (Probability Kill) is believed to be 70% against fighters. I dunno if anyone answered your question before but here it goes... Link to comment Share on other sites More sharing options...
GGTharos Posted February 26, 2005 Author Share Posted February 26, 2005 The Pk for the 120 was stated to be .75 ten years ago. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda Link to comment Share on other sites More sharing options...
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