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GGTharos

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Everything posted by GGTharos

  1. Thank You Maestro, I appreciate the reponse. I understand the choices for #2, but I think it is a reasonable argument to use simple PN - either you can guide with all the benefits of PN (like a heat seeker) or you cannot guide at all. Maybe ECM increases scintillation effects. I know you won't be making a lot of changes to ECM so may I make one suggestion to the missile guidance in HoJ: 1) Assume Vc is available, because we are only jamming range. Instead, make all range information invalid (eg. feed the missile 'range is 1km or 10km, whatever works best as a default) if the missile is launched without initial range knowledge (ie. launched in HoJ to begin with). This would get rid of maneuvering optimizations for long range shots. 2) You have a scintillation parameter for the miss distance which you increase when the target gets close to ground etc. Please increase it in the presence of ECM, even in 'burn through' range. Ideally more modern missiles should be less affected (less miss distance) and more ideally this should also depend on the ECM technology level, which means some sort of 'tech level' attribute would have to added to missiles and ECM systems - this without modeling different ECM techniques. 3) Actually, increasing miss distance in the presence of chaff would also be good ... no need for the missile to completely change targets.
  2. F-15 uses a 2.2 second update interval for TWS, 1.1 second for High-Data rate TWS. Because this is a MESA, the updates are not as accurate as AESA. This radar's rotation period is ~2 sec, and AESA will allow this target to be tracked through at least 120 degrees during the rotation (unlike a MESA which will 'sweep' the target for '1 radar hit', AESA will continuously track the target while it is in the field of view), so approximately 0.5 to 0.7 sec of continuous tracking with a 1.5 sec interruption. This is not a problem for radio correction.
  3. No, it doesn't make even a little bit of sense. There's no 'no escape zone' concept for a maddog - it is a visual mode, as in you're shoothing at something that you see in your HUD. The missile is active off the rail and its flight controls are immediately influenced by your aircraft attitude and lift vector, including g's you're pulling. This means tracking your target to some degree, not 20nm shots at 'unsuspecting targets' or shooting out of barrel rolls etc. While I don't think this is modeled in DCS, there's no condition here in which the missile would just turn around.
  4. That should be expected behavior unless you know something that the rest of us don't. AMRAAM chooses the trajectory on its own with knowledge of the TOF.
  5. That's right, ie for all intents and purposes: No one. That's a weird statement to make, and utterly meaningless. Tactics are made to ensure outcomes, if you can afford (as opposed to being forced) to be pessimistic you probably should be. It really all depends what he means by pessimistic.
  6. Sure there are, after all I have the DLZ, along with its listed limitations and those will have been refined by test firing the weapons. Unfortunately the same DLZ is subject to a loft algorithm that DCS does not provide (No, HB cannot do it - it's provided by the game and AFAIK cannot be overriden). But the question here, with respect to what you posted has nothing to do with the phoenix and everything to do with your impression oh how missiles should work at a certain altitude which again ... is not worth anything. You could always take missiles with known DLZs and compare, and then also pick up Fleeman's book and do the computation yourself using the basic shape -> drag coefficient assignment. While it's a far cry from a CFD, it gets you in the right ballpark for an evaluation of too fast/too slow. My point here is very simple though: If you're going to make the accusation, do the work.
  7. Could you please comment on these two items: Weapons. R-27 overshoots target every time in HOJ mode - fixed Weapons. R-27 missiles family and R-77 switched to true proportional navigation 1) What does it mean in practice - what guidance is used for HoJ? Will it apply to other missiles, and if not, why not? I am thinking sparrow mostly but there are others. Will you implement ECM more realistically, so that a dropped lock will also terminate HoJ? AAM HoJ typically depends on the jammer repeating the appropriate radar signal, rather than the ECM representation that is in DCS today - that means the ECM implementation in FC3 should change. 2) For the second item, what does this mean in practice? What guidance was used before?
  8. Based on what? If you have even back-of-the-envelope calculations to back that up, please share. Feelings are worthless in these cases. Math/physics is the only thing that matters.
  9. The difference between C5 and C7 is only in electronics - they use the same rocket motor. It would probably just have a better chaff rejection in DCS?
  10. There's nothing strange about it. Battery is what it is for technical and technological reasons. So you can't reach max aero, but there are advantages to be had before you reach it.
  11. In this case, HoJ on these particular types of missiles should only operate when they (or in the case of SARH, the carrier) are illuminating the target aircraft. The jammer should cease emitting when its duty cycle expires, so for fighter SPJs likely within a few seconds of illumination ceasing. ECM reduces Pk, it does not increase it (there may be exceptions, but I think for DCS this would be a case of newer missile vs older ECM) - HoJ is only there to make sure that Pk does not go to 0 hopefully. Specifically we're relying on the ECM repeating the radar transmission with 'bad info' and as such the missile should at least lose some of the vector information, be it range, Vc, etc. An angles jammer cannot be HoJ'd on easily (it makes no sense). Since all jammers in DCS are range jammers, the missile should lose range info from its PN computation, meaning if there is any path optimization done when launching the missile, it should go away and the missile should fly full PN all the way instead of 'restricted until range X. In addition, I imagine the ECM would just induce more scintillation so miss distance should increase.
  12. Sensor/processing capability goes to the 7M and later models. But ... does it really matter? The things we don't/won't know
  13. It's not 'best' or 'worst' or anything like that. It's the Sustained/Instantaneous turn rate measured at a given speed and g.
  14. Travel 45km at lo altitude, no. And also, what did you actually read? Travel or range? I bet it was range, and in that case 25km at low altitude could maybe make sense, and 45km at medium altitude. Altitude does not affect range linearly, but you could ballpark high altitude range to be 4x low altitude range. Still, 25km is a long range at low altitude and likely assume something relatively easy ie. non-maneuvering and traveling high subsonic, like M0.8.
  15. Maybe compared to a family model. It definitely will not be superior to a light grey. The loss comes from the nose weight and the same is experienced by the family models.
  16. Simulating radar cells in software is not impossible but it is tricky, and in particular it adds complication of the 'ok well I can see only one target but why does the AI see everything', actual programming challenges aside. You could probably represent the radar bins reasonably well using a sparse matrix. It's not an eagle problem ... in fact the eagle had some of the best break-out capability out there. AESA radars today make everything back then look like a joke though. On a practical level, it reduces the notch size. There are tradeoffs (more false returns etc) which are only nebulously talked about.
  17. .... and we start to pick them up as they're in their beam maneuver (he alludes to but does not describe the counter). So great, you found one of the few times this happened I don't know if there was something said about this in the rest of the video, but it has nothing to do with the notch.
  18. Yes look up the event, I know what you're talking about. It's not the simple fact you stated
  19. Often failed to notch, not often notched. Yes, there were situations where the initial geometry was bad but that wasn't a deliberate act.
  20. The Phoenix works just fine against fighters. The limit depends very heavily on what your target is and that it is doing, and what you are trying to accomplish. People covered a bunch of stuff, specially altitude. There's usually little reason to shoot at a fighter beyond 20nm, and at that distance you ensure the missile will reach its target. More like it means 'it should have gone active at this point' I forget how the entire process is mechanized in DCS - even if the track is lost the missile should go active as long as you don't delete the track and the radar is looking in that direction (the missile data-link commands the missile to go active - this should be different for the C, which should be doing it's own thing by itself). Rule of thumb 2sec/nm head on, 3sec/nm on the beam, 4sec/nm tail-chase. Still seem high? The missile lofts in order to increase its range. ... no Bring friends. There exists no other 'best tactic' against multiple fighters, only 'best you can do at this time' and those are all 'it depends'. You have to analyze the situation and figure out what you're going to do, including turning tail and running. Maintain the target in the radar cone until the missile is active. No, you cannot, unless you launch it in specific modes used for close combat. They won't seem to go active if the track is lost (they may be going active and not detecting anything), or if you launch in STT (The C should be an exception here but again, I don't know how it behaves in DCS).
  21. Here's another bit of non-propaganda propaganda for you then: This is the original APG-63, in the F-15C the worst tuned MSIP radar performed as well as the best tuned original radar, all according to real pilots as well. It's definitely notchable as seen in real combat, but also in real combat this has rarely been an issue - why? We don't really know.
  22. Can you actually say what you want instead of beating around the bush?
  23. I believe that the difference is in the IR spectrum, where if the exhaust is perfectly hidden, IIRC it requires a sensor capable of detecting longer IR wavelengths - so basically an all-aspect missile. I recall a paper that describes how to compute the intensity of the target based on a number of things, including the emission area (this is significant because if an aircraft and a missile are seem from the front, both heated up to the same temperature, the missile will still have a smaller signature - same idea as fighter vs bomber).
  24. So this aircraft turned nose on, presenting the smallest heat signature it could, while the tanker flew behind it with at least two hot exhausts, plus itself, in view. The distance does make a difference but it's also hugely aspect dependent. What does the radar have to do with it? Basically the radar points the seeker in a specific direction and hopefully the seeker of the missile will 'cage' onto whatever it sees there. But the missile will be doing its own thing. IRL you'd see HUD indications of the missile changing its mind, which doesn't happen in DCS: In DCS, the spawned missile has nothing to do with that your aircraft pretends it's doing while 'on the rail', and that inconsistency is a problem. But there's an important lesson here too, which also applies IRL: Do not shoot if there is, or there will be a friendly entering the seeker FoV during the missile's time of flight.
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