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I have already watched it all thru. Nothing sufficient new for me. What clutter we talking about?? Sidelobe? Mainlobe harmonics(which indeed may be shifted with PRF chnging)? Or we talking about mainlobe central line clutter? - (I talking exactly about this thing) Page 61 directly tells about situation we have see in track from first post.

That all well known. At the moment very low S/N chosen(2 dB only) for target detection assuming effect of PDI. Regarding sigma values - now its some averaged value depending on incidence angle. I saw this earlier. it assumes unambiguous range. That's correct value(you may estimate it knowing antenna diameter and carrier frequency). You can't obtain narrow beam with small dish. Also 15 degrees circle you can see on F-18s HUD in amraam visual mode. For AIM-7 it will be 12 degrees.

From your own link

Ok, then please, tell how you will resolve ambuguties and seprate target from clutter signal if all range bins filled with clutter? A long time ago

Oh..you really think I do not know about abmiguty resloving? The thing is.. you can perform such resolving for separate relatively small target. That would not work when you have such extended "target" as clutter.

10KHz is not HPRF. Its a lower bound of MPRF. RCS increasing at perpendicular angles of sight is also implemented and gives up 40 times increasing in RCS. Before saying somthing about visibility of tagets above clutter it's better to calculate it. Otherwise it's just assumptions. I know that. pitch-AOA means pitch minus AoA, that gives direction of velocity vector.

Guys, unfortunately I have no time to answer your every question rigth now, so there is drawing with rundown on missile behavior in TS track. Missile at high altitude and looks down at shallow angle, so footprint is a huge ellipse. Yes, different parts of footprint located at sufficiently different distances and returns different amount of power, that calculates accroding to radar eqation. Normalized surface RCS depends on angle of incidence as it should. So there is no errors in modeling power of mainlobe ground return I suppose. Range of notched radial veloctites depends on missile velocity, mainlobe width and mainlobe-surface interseсtion geometry(angles between LOS and surface, missile velocity vector and LOS). Let's consider moment when one of missiles in TS track looses target and estimate notched velocities range at this moment. Missile velocity is 678m/s, missile pitch-AoA angle is -25 degress, seeker deflected 16.5 degress down. Surface radial velocity in direction of LOS will be 678 * cos(-25 +16.5) ~= 671m/s. Radial velocity of upper mainlobe bound will be 678*cos(-25+16.5-7.5) ~= 652m/s. Radial velocity of upper mainlobe bound will be 678*cos(-25+16.5+7.5) ~= 678m/s. So full range of notched velocities is 678-652=26m/s. Why ranage gating does not help in this case? Because of range ambiguity. For 10KHz PRF maximum unambigious range is 15km. Lower PRFs(provide bigger unamibgous range) not practical for several reasons. From simple geometry calculations we can obtain that closest point of surface lay at ~29km distance and more far point at ~75km. So the range of ground return ranges is around 46km. Due to range ambiguty ground return fill all range bins 3 times (46/15~=3). Dispite of long ditances such return still may mask target due to huge footprint area. Why missile do not extrapolate target position after lock loosing? It's extrapolete, but not very good due to lack of datalink updates. When seeker looses target missile guides on target INS-predicted position, but INS cant predict manuevers.

Intended. Launcher aircraft drops target lock => drops datalink, then target begins to dive, goes thru notch(dropping missile lock) and out of missile FOV. You should keep lock until hit to maximize Pk.

Unfortunatley, I can not reproduce this too. Guys, did you instal/remove any mods eralier? If yes please try to repare DCS. If no, I would like to know some additional info: if you play track several times(say 5) in a row you always get the same result? if you play track the same 5 times but with DCS restarting after each replay do you see any difference?

Yep

Hi GGTharos, good if pilots have data from instrumented shots, but even if they be able to talk about we would need data for set of shots to understand how the avarage missile looks like.(There is always some uncertainity due to different air and motor charge temperature, some devation on total impulse, hence there may be deviation on that Mach 0.2 or so) Regarding AIM-7 guidance - it's not related thing(and it works correct). If we talking about top speed/ballisitcs we should assume that missile fly stright ahead without any maneuvers. Manuvering is a separate case. BTW I'have found that nozzle exit area was not defined for AIM-7 family in OB. It was fixed internally, but not released. We will include it into the next patch. That will give missile additional 0.1 Mach of top speed Another interesting thing is AIM-7 radome. It's different for an old and newer versions, see attached. Right now we have drag of old radome with a higher Length/Diameter ratio for all aim-7 versions. I plan to run CFD someday to find out the difference in zero-lift drag value. Think it may be 5-10% higher for M/H/P versions of missile.

Of course What parameters you suppose to launch missile at to reach Mach 4? Right now launched at 60Kft and Mach 2 missile speeds up to Mach 4. To make missile able to achive Mach 4 at 40Kft altitude (launched Mach 2) you should spent all fuel for boost. And there is no issue with drag. See attached. Three different sources(Tactical missile design by E. Fleeman, raytheon wind tunnel test data - denoted by triangles, our CFD validation - denoted by x'es) give almost the same values. Also see motor data from Feelman's book. Who is SME in that case? Pilots do not need to know such things. Raytheon engineers? Not an option. Guys, all this sounds like you think we do not analyse data we have, do not see mistakes, do not do research. But we do. We try our best.

There is no underperfoming. We have solid info on Sparrow rocket motor and drag. Designation-systems table is not pretty reliable source. Hoverver, AIM-7F/M/H can reach Mach 4 above 15000m altitude and launch velocity about Mach 2.5. FYI

Fixed internally

Guys, we appreciate your feedback, but at the moment we do not need new tracks(existing ones is enough). We plan to make some tweaks and publish a report with clarifications on the notch and radar modeling. Thanks.

Smaller size make sense-more room for battery, efficency improvement of circuits I suppose not so signinficant. Moreover, main power consumers is transmitter and fin servos. BTW, control section was shortened too. Less room for servo battaries?

We will revise power supply lifetime for C version. But it not possible just to increase battery lifetime IRL. There are several limitations: available room, allowable mass excess(impact on ballistics), reasonable lifetime also limited by overall control system/INS accuracy.

It's not the same. Please watch tracks form your previous post. Missile hits the target in all these tracks now.

R-33 ballistics is correct(yes, it's slightly worse than R-27ER). R-33 outclassed by R-40 because R-40 overperformed and requires adjustment.

Была киберпрокачана. Мы сделали матмодель ПВРД для нее, откуда в переводе взялись воздухозаборники - неизвестно. (EN changelog: Kh-31 missile. Added realistic ramjet model and flight data.)

Very simple, because it's a bug. Target position and velocity, bur there should be no such info passed to missile in VISUAL mode.

Not a missile issue. Aircraft pass target position to the missile INS and missile goes to that position. Unfortunately video is useless for bugfixing. Could you please provide a short track?

Any file storage is suitable. Just PM me.

Thanks for your help! Unfortunately, videos are useless for debugging, but short tracks(from shooter and observers sides) may be much more helpful.

Guys, in the video missile TOF ~10 seconds. This is close range, loft is not needed in such case. Unusual trajectory bending caused by advanced guidance law. Modern missiles do not use conventional PN(with except of IR perhaps). Парни, время полета ракеты в видео около 10 сек, это ближняя дистанция, лофт как таковой здесь не нужен. Необычное искривление траектории скорее всего вызвано улучшенным законом наведения. Современные ракеты ПН в чистом виде уже не используют(ну может за исключением тепловых).