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nighthawk2174

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Everything posted by nighthawk2174

  1. The issue here is that in MPRF when you feed the returns into the associated apparent range bins then feed that into the attached doppler bins a good portion of that clutter will fall into another doppler bin whereas the target will be in one range bin. This will reduce the amount of energy that the target return has to compete against to whatever happens to fall into the same doppler bin. The MLC is not all at the same doppler as the target and the larger the look angle and the larger the velocity of the missile the more that energy is distributed. Were in STT not search as well, currently it seems that the notch is 100kts'ish hopefully you can give the exact number. But In STT your tracking gates are going to be much much smaller then this. Typical values I see referenced are 15m/s in total width. And the missile should really only loose the tracking gate if the target is not competing with clutter. But that would mean that you could get a lot closer to the central MLC return (especially at close range and for high RCS say being side on or given your belly to the target) without loosing track. If not right on it if the noise is low such as in only very low look angles or low return clutter like calm seas. Also we can't ignore factors like integration time and PDI for S/N.
  2. Yeah seems this is part of the notch behavior discussed before: my thoughts on the matter are layed out in this thread.
  3. I'd seen some documents reference two different nose cons for the 7F one that is better for the sensor and one better for aero performance i'd just never seen the difference. Do we know which one was in more common use? edit: Didn't the 7M get another redesigned nose again from the 7F? From just one quick image grab it seems that it's closer in shape to the older but more aerodynamic nose cone:
  4. There will be at some point it will be able to go active on its own. Currently the only benefit is better chaff resistance.
  5. The AIM-120 has an INS so by default its going to know the targets location in 3D space. You could easily look for a split S based off of this information. We know from documentation that there is a method by which there are adjustments made to compensate for the split-S on the AIM-7. I highly doubt the amraam would not have something similar if not even better.
  6. According to razbam's galinette DCS was only returning a constant value for the RCS even when side on. I linked him to your post and I think he said he was going to talk to you. Are you sure this is implemented?
  7. Yeah i'm still a little fuzzy on this but don't rage bins come before the Doppler filters?
  8. Part of what's going on here too, aside from mprf stuff as i'm not quite up far enough in my reading to know the exact answer I know it can be done though. We can't ignore S/N either, i've seen missiles notched at less then two miles. Except that there's a ton of things that should make the target compete even against a large MLC. The STT nature of the track ensures that integration time is extremely high effectively infinite, monopulse itself also has S/N benefits, side on RCS will be huge as well, the employment of PDI will also help. The type of terrain would also be important: https://patents.google.com/patent/US4559537 method of tracking targets in MLC patented by Raytheon in 1985 right when AIM-120 development was in full swing. Also from earlier are you using 15deg for the beamwidth for the amraam? That's huge way beyond a reasonable value. MACE uses a value of ~3-4deg Edit: The video posted by Vatikus is exactly how you deal with mprf ambiguities i'm still working on understanding the exact mechanisms behind mprf but as shown in the vid it can be done easily. There's a reason MPRF is so widly used.
  9. PRF jitter has issues it reduces range what radars use now if PRF switching. You switch between a few distinct PRF's usually 3-4 and get the same effect without as many issues.
  10. You absolutly can in MPRF especially in a monopulse seeker with its extremely good range resolution, especially in mprf. And considering the amraam's lack of need for long range I don't doubt its pulse width isn't quite small fractions of a microsecond. Not to mention other techniques developed to break out closely spaced contacts. Which monopulse seekers are capable of determing and even partially solving for multiple contacts inside its resolution cell.
  11. So RCS increasing when side on is implemented now? Also I know that there are references even the AIM-7 docs to "anti-Split S logic". Exactly what this entails is not discused but its not hard to make a reasonable guess. Its almost certaintly just a damper put on the acceleration command if the targets angular position and velocity meet a certain set of criteria. As such the flight path would look like the red line below instead of green which is what it does now: You can solve for range ambiguity even in HPRF just use PRF switching. Sorta, HPRF seekers are highly ambigous in range so i'm not sure if the ku/ka band amraam seeker would even have an unamiguous range of even that far. Its hard to range gate with HPRF as due to the range ambiguities its hard to seperate clutter from the target when putting returns into the range bins. Exactly Ontop of all of this Monopulse systems are renound for massive S/N gains over even planar arrays. Which would help even more. And yes range to ground clutter and type should be factored in I don't know if it is currently.
  12. I think that implementing them will be important. From aim-7 data it can be as much as 15+% reduction in drag. I really hope you guys do add these effects. For the aim-54 this would be super important due to the low thrust but high burn time.
  13. I've not noticed any changes and from the above tracks i'm seeing the 9X pass well within 7m.
  14. @IronMikeIs the missile fully on the new ED FM? Also are motor on drag reductions a thing?
  15. Yeah some tests of my own indicate that nothing has changed as well. Thanks for doing the leg work on some tracks.
  16. bump will have been a year since the last post and more than 2 since I was asked to make this thread by an Ed team member. Is this ever going to be fixed?
  17. Before the LD-10, which is the same body as the SD-10 and almost certainly the same motor, was significantly overperformaing:
  18. One of the problems with missiles right now it seems that they will pull beyond their seeker gimble limit causing an immediate break lock, that happened a few times in the testing vid above. Additionally split S wise I know that the AIM-7F/M had anti-split S logic. What this exactly this entails is not publicly available but it's not hard to to predict what it does as there's really only one logical possibility. It's almost certainly as simple as an acceleration damper that is enabled so the missile doesn't over pull but stays above the target. Maybe not relevant for the 54A but the 54C i'd be shocked if there wasn't something similar. Maybe something to consider looking into guidance wise ontop of the missile pulling in the the loft instead of following a low G ballistic trajectory.
  19. Yup which is really the big issue here, to really know for sure were going to need an actual motor thrustvtime graph. Until we get one though the fleeman numbers are the best we got. I don't disagree with your conclusion though GG I'm also of the opinion it may be a little slow.
  20. Ohh never seen that manual before thanks for a link! Has there been any changes in regards to the proxy fuzes may be worth asking about. To see if it’s build or track related.
  21. Yeah i did the math that would line up as a possibility. It’d help if we had more info, boost sustain motors are highly variable in how they can be set up.
  22. Except for the videos given here, and in other threads. It is happening and not infrequently, and the fact the tracks aren’t living up shows either something has been changed on your guys version or tracks are just broken.
  23. Yeah this has been my experience in sp as well. If it’s a direct hit it’s fine but if it’s close 80+% of the time it’s this. To me looks like the amraam is about 1.5-2 missile lengths away from the jet which would be 5-8m. Well within the 12 or so meter proxy range typical of these kind of missiles.
  24. It was on the Russian forum missile thread, I don’t have time to find it now though.
  25. It was stated a while ago that a new or improved (forgot the exact language) proxy fuse system was in the works.
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