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Whiskey11

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About Whiskey11

  • Birthday January 21

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  • Flight Simulators
    DCS World 2.5, Flight Simulator 2020, X-Plane 11
  • Location
    United States
  • Interests
    Cars, Guns, Airplanes, Warships, Video Games

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  1. The AIM-54 loft profile is BEAUTIFUL now, just wish some of the other guidance quirks were worked out... specifically the lateral guidance being behind the "curve" so to speak. It's a lot of fun watching an AIM-54A Mk60 loft to 170k feet and come down at Mach 3 on a target 120nmi away! I posted more detailed feedback in the AIM-54 discussion, with track files and Tacview for your viewing pleasure
  2. None of these shots are manually lofted except maybe Cole's... mine were launched as close to zero vertical speed as possible.
  3. Here are the track files I couldn't post due to attachment size limit per post. F14MissileGuidanceTest54AMk601.trk F14MissileGuidanceTest54AMk602.trk F14MissileGuidanceTest54C2.trk F14MissileGuidanceTest54C1.trk NOWWhatIstheAIM54ADoing.trk
  4. Hello, it's me again with more Missile Guidance Quirky Fun!!!!!! On today's episode, attempting to get an AIM-54 variant into space! Also, maybe an exaggerated case study on the lateral guidance issue I brought up earlier. And finally, we look at the AIM-54C putting on it's best glider impression! You are probably wondering how I got here, so Test Setup: F-14: 33k feet, Mach 1.8(ish), travelling due north Su-33: 36k feet, Mach 0.75, travelling HDG 210º - Set to Not React The first set of shots I performed were using the AIM-54C and AIM-54A Mk60 at ~70nmi. Lateral guidance is improved compared to the previous tests, but the problem persists in both cases. I stepped this out to 85nmi to exaggerate the arc, and it got worse. This got me thinking about the lateral guidance issue some more... a huge chunk of what I'm guessing is missing from the "equation" here is air resistance. At shorter ranges, it largely doesn't matter, but at the longer ranges, the difference here is quite large. See the picture below: The above picture is a shot taken at 115nmi in STT against a Mach .65 Tu-95 at 36k feet. The Missile is an AIM-54C. It hit a peek altitude of 150,020 feet!!!! As it was coming down in the loft profile it started pulling massive lead to try and catch up to the Tu-95 it was now trailing behind (showing the incorrect computed impact point). As it got lower in altitude, it pulled less lead because the air resistance was actually providing the desired corrections as the fins started to work correctly. Thing is, this missile MISSES the target, but not because of any lateral issue. It ran out of battery. We'll talk about that here in a second though. Because I was using the AIM-54C, which is slower, I decided to switch to the AIM-54A Mk60. The results were frightening... In terms of lateral guidance, the AIM-54A Mk60 has the same issue at these ranges. The difference is the AIM-54A Mk60 is moving fast enough that the computed lead angle is "more" correct, so while there are still large corrections in the lateral guidance as it comes down from the bozosphere is "more" correct. Also, speaking of bozosphere trajectories... the AIM-54A Mk60 hit a PEEK ALTITUDE of 171540 feet. For perspective, I'm at 33k feet, and space starts around 328k feet... so half way to space! The AIM-54A Mk60's faster speed, and higher peek altitude actually gets it to the target with time to spare on the 240 second battery life. Impact speed, just over Mach 3.0!!!!!!!!!!!!!! The impact angle is also B-E-A-UTIFUL! Money!!!! Lateral Guidance Lesson Learned? nullClearly the issue here is a combination of air resistance (actually, lack thereof in the mid course), and the initial launch angle being incorrect. The two, together, cause for some interesting energy bleed at long ranges and the "arc" in the lateral guidance... Because I'm not 100% familiar with who handles this in DCS, I'm not sure if this is a Heatblur thing or a ED thing? I'm guessing it's an ED thing after launch, but before and at launch is Heatblur? Maybe @IronMike can share some insight? To SPACE!!!!! Well we didn't quite get there... in fact subsequent attempts to shoot at things at excessive ranges resulted in some uhhh... interesting behavior.... but not exactly space. The only thing really interesting to report is the ability to smack Tu-95's and Tu-22's at 160-165nmi ranges with the AIM-54A Mk60. I was able to hit my Tu-95, from 45k, at Mach ~1.75 at ~161nmi in PDSTT... @777coletrain was able to smack his Tu-22 at 165nmi IN TWS only going Mach 1.2 at 42k. Yeah, that's pretty epic! Loft Profiles and AIM-54C Glider Competition Where things get interesting is the loft... maybe not the actual lofting maneuver, that looks pretty good, but the glide down from max altitude... in shots above about 80nmi, the AIM-54C starts the descent to the target earlier than the AIM-54A and then does a linear (vertically) intercept. The AIM-54A Mk60 comes down in a nearly perfect ballistic arc like we'd expect. Not sure what is going on with that vertical guidance, but this is what it looks like: The AIM-54A Mk60 at slightly longer range in comparison: I believe this has already been brought up to Heatblur/ED before, so I'm not going to keep posting about those tests. Conclusion I believe the lateral missile guidance issue is related to a combination of incorrect original lead angle, and lack of air resistance calculations being factored in or some combo of both. The vertical guidance issue is at least known, so I'm not going to beat that drum any more than I have. I'll post track files in a follow on post. F1454AMk60Test1.acmi F-1454CTest1.acmi F-1454CTest2.acmi WhatistheAIM54Adoing.acmi WhatistheAIM54doing.acmi
  5. Pictures taken by a local on the [107th] JAS Through the Inferno Server! Photos credit to Warden, rehosted and posted with his permission!
  6. Ballistics includes lateral changes as well as vertical and longitudinal changes... it's the study of the motion of projectiles in flight. Nitpicking aside, I'm pretty sure this was fairly well studied, and I'd be shocked if the AWG-9 couldn't perform at least rudimentary calculations for this in near real time given how much a small error like that would make a difference at the massive ranges of the AIM-54's expected flight profiles. Again, the whole premise is for the AWG-9 to put the missile in a place where when it goes active, the seeker is pointed more or less at the target. Ignoring the effects of drag in this equation would be a huge mistake and it'd never hit the intended target. There is that too... if you download the tacview, the impact point for this shot puts the Su-33 basically dead ahead of the F-14... if the computed impact point at launch was correct, the Missile would have came off effectively dead ahead, but it didn't, it came off and went right. I posted in my response to IronMike that in TWS the steering T was pointed to the right, but was dead center in PD-STT. The missile behavior was essentially the same (see the track files). So if centering the T was the issue, I'd expect the PD-STT shot to have been a straighter path... and it actually wasn't any straighter (arguably the impact angle was worse), hence my post about the guidance issues!
  7. Alrighty, so yesterday, I decided to do some testing with the Phoenix after the patch went live. I noticed a long time ago that it seemed like the Phoenix TWS Trajectory doesn't make a lot of sense to me. What I noticed is it would launch and go into a pure pursuit in TWS. This, isn't a real big issue, except that it isn't actually calculating the pursuit angle correctly and actually makes an arc to the target rather than flying to the computed impact point. This was contributing to the "self notching" behavior of the missile. So here is my test parameters: Map: Mariana's over the ocean pointing towards nothing but ocean Launch Aircraft: F-14B, ~33k Feet, Mach 1.21 AIM-54C, Course: Due North Target Aircraft: Su-33, ~36k feet, Mach 0.75, Course: ~210 degrees, Set to Not react (so no maneuvering, changing speeds, or deploying countermeasures, etc) Distance at launch was 67.1nmi with the above parameters. Here is a picture of the course the AIM-54 took to guide in on the Su-33: See the left hand arc in the trajectory? Seems counter intuitive. The Su-33 is not changing speed, not changing heading, nor changing altitude. It's constant. To me, the arc does not make logical sense. Why would this missile not leave the aircraft and turn to the "perfect" intercept point to impact the target without making any other turns. Again, the target is not maneuvering (no altitude or heading changes) or changing speed. The impact point should be fixed in space such that the missile goes active without maneuvering laterally beyond the initial turn to the intercept point. I should point out this problem ALSO exists in PD-STT at these same ranges although the steering que for launching in both TWS and PD-STT is different. I'd also point out, that the computed impact point, FOR THIS SCENARIO, should not change at all from the initial one because the aircraft is not maneuvering or changing speed. With that in mind, I don't think the TWS track refresh rate matters for this particular case. Because I'm slightly crazy, I repeated this test with the AIM-120C and the F-15. The AIM-120C's lead angle on a ~45nmi shot is far closer to a straight line, but it still makes the turn. I also performed these tests with the F-16C (33k feet, Mach 1.56) with both the AIM-120B and the AIM-120C but the shorter launch ranges (~20nmi) showed a nearly straight line to impact, which makes sense given the time of flight of the missile. I fully realize there is a "balance" between the missile making its initial turn and energy, but this seems like that computed impact point is very wrong for the AIM54/AIM120B/C and it is computing an impact point which is closer to the target than it should be. The end result is a missile which is easier to notch because it's "behind" the pursuit curve. Hopefully Heatblur or ED can shed some light on the guidance issues seen here! Thanks! This is mostly a copy and paste of my post to Heatblur on the AIM-54 Feedback discussion, but in case this falls under ED's wheelhouse, I wanted you guys to be aware too! F-14AIM54Test1.acmiF-15AIM120CTest1.acmiMissileGuidanceTest2.trkMissileGuidanceTestF14AIM54C.trkMissileGuidanceTestF15TWS120C.trkMissileGuidanceTestF15TWS120C2.trk
  8. It certainly seems the issue in this thread has been addressed... a squadron mate and I were testing guidance issues with the AIM-54 against F-15C launched AIM-120C's and he was taking shots at 60+nmi and landing them against maneuvering targets.
  9. I wouldn't think it would necessarily need to guide towards a point in space (although I imagine that is how the missile does it IRL, with the AWG-9 updating that point in space) vs constantly guiding on the target. I posted the extreme case above (with tracks and Tacview files) where the target is not chaffing, flaring, maneuvering or changing speed. The impact point, even if guiding on the target, should never change, and thus the missile itself, should not be maneuvering, let alone the gentle arc it takes after launch. The target launched on in my test was not an extrapolated track either. Constant TWS track from before launch to launch. When I tested it in PD-STT, the behavior was the same. The ONE change between the two was the difference in the steering T... on the TWS shot, the steering T was to the right of my flight path. In PD-STT it was nearly centered. This did NOT change the missile's behavior much... Actually, in PD-STT it had a more aggressive arc to the target than the TWS shot. Because I knew the AIM-54 is in the weird hybrid zone between Old and New API's, I wanted to test the AIM-120C in the same scenario. The results were better, but the range was less (~45-55nmi shots). It still had a gentle arc on a non chaffing/flaring, maneuvering or changing speed target. That at least suggests the guidance issue is present in the AIM-120C. I'm NOT sure if this is an issue with how the game handles missiles or not. What I mean is, I don't know if guidance is being done by the aircraft and the missile is commanded to move (as it would be IRL) or if it is doing these guidance things on their own (the missile knows where it is). If it's the former, than the issue is in the F-14. If it's the latter, it's ED, since they have control of the missiles in game. I'm pretty confident, the ballistic path of these missiles was well studied and accounted for.... and even if it was the case it wasn't, the arc would be the OPPOSITE of what we see right now. Specifically, it would be overshooting the impact point (assuming less losses than reality) and curving towards a more straight impact vs now where it is UNDERSHOOTING the target and having to play catch up, effectively self notching.
  10. Alrighty, so today, I decided to do some testing with the Phoenix, but not what everyone else is testing. I noticed a long time ago that it seemed like the Phoenix TWS Trajectory doesn't make a lot of sense to me. What I noticed is it would launch and go into a pure pursuit in TWS. This, isn't a real big issue, except that it isn't actually calculating the pursuit angle correctly and actually makes an arc to the target rather than flying to the computed impact point. This was contributing to the "self notching" behavior of the missile. So here is my test parameters: Map: Mariana's over the ocean pointing towards nothing but ocean Launch Aircraft: F-14B, ~33k Feet, Mach 1.21 AIM-54C, Course: Due North Target Aircraft: Su-33, ~36k feet, Mach 0.75, Course: ~210 degrees, Set to Not react (so no maneuvering, changing speeds, etc) Distance at launch was 67.1nmi with the above parameters. Here is a picture of the course the AIM-54 took to guide in on the Su-33: See the left hand arc in the trajectory? Seems counter intuitive. The Su-33 is not changing speed, not changing heading, nor changing altitude. It's constant. To me, the arc does not make logical sense. Why would this missile not leave the aircraft and turn to the "perfect" intercept angle to impact the target without making any other turns. Again, the target is not maneuvering (no altitude or heading changes) or changing speed. The impact point should be fixed in space such that the missile goes active without maneuvering laterally beyond the initial turn to the intercept point. I should point out this problem ALSO exists in PD-STT at these same ranges. I'd also point out, that the computed impact point, FOR THIS SCENARIO, should not change at all from the initial one because the aircraft is not maneuvering or changing speed. With that in mind, I don't think the TWS track refresh rate matters for this particular case. Because I'm slightly crazy, I repeated this test with the AIM-120C and the F-15. The AIM-120C's lead angle on a ~45nmi shot is far closer to a straight line, but it still makes the turn. I also performed these tests with the F-16C (33k feet, Mach 1.56) with both the AIM-120B and the AIM-120C but the shorter launch ranges (~20nmi) showed a nearly straight line to impact, which makes sense given the time of flight of the missile. I fully realize there is a "balance" between the missile making its initial turn and energy, but this seems like that computed impact point is very wrong for the AIM54 and it is computing an impact point which is closer to the target than it should be. The end result is a missile which is easier to notch (because it's "behind" the pursuit curve). Hopefully Heatblur or ED can shed some light on the guidance issues seen here! F-14AIM54Test1.acmi F-15AIM120CTest1.acmi MissileGuidanceTest2.trk MissileGuidanceTestF14AIM54C.trk MissileGuidanceTestF15TWS120C.trk MissileGuidanceTestF15TWS120C2.trk
  11. I've actually had quite a few "track hold" contacts get an active AIM54 command sent... what I have YET to have happen is the AWG-9 correlate a dropped track with a track hold when it is regained, even if the track is almost exactly where the "track hold" track is at. Given DCS's netcode, if you see the dreaded X, you will probably never get the track back.
  12. Are you playing on the Open Beta branch of the "Stable" Branch? I'm not sure if the AH-64 has reached the Stable branch or not. It IS available on the Open Beta branch.
  13. It's been a rough learning experience for me... I've flown the Ka-50, the UH-60L, and the UH-1H fairly religiously prior to this, and just can't get the handle of transitioning to a hover. Seems excessively twitchy in all axis even with massive curves. It's like you get sub 40 knots or so and the entire aircraft wants to go into a fast flat spin. I have a hard time believing the real helo is this twitchy at low speeds... If it is, then I guess I'll just have to hope for an AH-1W or AH-1Z for a modern attack helo with FLIR...
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