yngvef Posted October 18, 2019 Share Posted October 18, 2019 I've tried multiple times with different loadouts in the exact same mission, same temperature (20c) and no wind. Dropping with CCIP at a 25-30 degree dive angle and 450ish knots. The Mk-82 hits the target pretty much dead on. The Mk-83 falls a bit short (maybe 50 meters) The Mk-84 falls a lot short (maybe 100-150 meters) And it's always short. It never overshoots, which makes me wonder if this is a bug. Maybe the fall calculation is wrong for the heavier bombs. If it had missed sometimes too short and sometimes too long, I would expect it is just the inaccuracy of the weapon, but when it consistently drops short, I think it's something else. Has anyone else noticed this? It may be an issue on other planes as well (had similar results in F-16), meaning there could be something wrong with the calculation of the Mk-83 and Mk-84 across the board. did the atmosphere model change recently? PPS: I tried searching the forum before posting, but I only found an older thread regarding auto bombing mode, but that seemed like a slightly different thing, so I made this thread. Link to comment Share on other sites More sharing options...
yngvef Posted October 18, 2019 Author Share Posted October 18, 2019 Did some more testing. And in Nevada, it seems that the bombs hit their mark fairly well, but in the Persian Gulf, I see the heavier bombs falling slightly short of the aimpoint. Link to comment Share on other sites More sharing options...
ED Team BIGNEWY Posted October 18, 2019 ED Team Share Posted October 18, 2019 Please attach a short track replay thanks Forum rules - DCS Crashing? Try this first - Cleanup and Repair - Discord BIGNEWY#8703 - Youtube - Patch Status Windows 11, NVIDIA MSI RTX 3090, Intel® i9-10900K 3.70GHz, 5.30GHz Turbo, Corsair Hydro Series H150i Pro, 64GB DDR @3200, ASUS ROG Strix Z490-F Gaming, HP Reverb G2 Link to comment Share on other sites More sharing options...
yngvef Posted October 19, 2019 Author Share Posted October 19, 2019 Added files showing what I mean. I tried as much as possible to make the situation identical in all three attempts. For some strange reason, the bomb pickle button didn't always register on the first try (different bug? or something I did wrong perhaps?). So on the 83 and 84 video I ended up dropping one into the ocean just to make sure the button would work when the pipper passed the target. Now, the bombs don't miss by that much, but enough that it's quite noticeable. And enough that I didn't damage the target with the 83 and 84, while the 82 destroyed it. And, once again, they always fall short, never long. PS: I usually don't do a -1.5 g push to enter the dive, but I wanted all the parameters to be as identical as possible (and the tracks as short as possible), so i didn't do a proper break into the target. But I've had the same results regardless of how I enter the dive.MK-82 Direct Hit.trkMK-83 falling short.trkMK-84 falling short.trk Link to comment Share on other sites More sharing options...
Preendog Posted October 20, 2019 Share Posted October 20, 2019 (edited) yngvef, when I watch the 83 and 84 tracks, I notice you pickle slightly before the CCIP reaches the target. Here's a pic of the 83 drop, taken 1/10th of a second after you hit the button, when the vertical line disappears: In the 82 track, you still pickle early, but it is not as bad. The random drift of the bomb may have made it hit. I don't know if different bombs have different random drift, but it's significant. Maybe try aiming for the roof of each target? That's what I do. It also helps to unload a little just before release, like 0.25G, so the pipper isn't moving over the target so quickly. Bombing at a steeper angle helps too. Edited October 20, 2019 by Preendog Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 I realize that CCIP has too many unknown factors, as well as the human factor, so I tried out CCRP level bombing under similar "clinical conditions" (as in, same conditions for all: 10k feet, 300 knots, no wind) and the results are very clear: The heavier bombs fall short. Added tracks for CCRP bombing. This removes the human factor, as I use the TGP to designate the aimpoint, and can watch the impact on the TGP compared to the calculated aimpoint. Every flight involved 4 bombs (one on each wing pylon). All were dropped at the same time. Mk-82 straddles the target. Mk-83 and Mk-84 falls short.CCRP Mk-82 direct hit.trkCCRP Mk-83 Falls short.trkCCRP Mk-84 Falls short.trk Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 The Mk-84 misses the most, so it seems to scale with the weight of the bomb. Can a mod change the title to include that this also happens in CCRP mode? Link to comment Share on other sites More sharing options...
ED Team BIGNEWY Posted October 22, 2019 ED Team Share Posted October 22, 2019 Hi We do have MK-84 falling short reported for F-16 it maybe related I will look into it. Forum rules - DCS Crashing? Try this first - Cleanup and Repair - Discord BIGNEWY#8703 - Youtube - Patch Status Windows 11, NVIDIA MSI RTX 3090, Intel® i9-10900K 3.70GHz, 5.30GHz Turbo, Corsair Hydro Series H150i Pro, 64GB DDR @3200, ASUS ROG Strix Z490-F Gaming, HP Reverb G2 Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 Yep, it seems it's an issue across multiple planes. Just tested A-10C and F-16C as well. The A-10 didn't miss as badly, but the F-16 missed very badly. And when i look at the replays, it seems that the aiming error gets larger with speed (which makes sense). The A-10C was only at 260-270 knots, while the F-16C was at 330 (if memory serves). This is probably a global issue, and not just an F-18 thing.F-16 CCRP Mk-84 Falls short too.trkA-10C CCRP Mk-84 Also Falls short but not as much.trk Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 And, though I haven't tested, I assume the Mk-83 also falls short, but not as much. My findings: The higher the bomb weight, and the faster the drop speed, the bigger the error. Link to comment Share on other sites More sharing options...
QuiGon Posted October 22, 2019 Share Posted October 22, 2019 I've also noticed the Mk-84 is falling quite a good bit short, when I used them with the Hornet on the Caucasus map in CCIP attacks a few days before. Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit DCS Panavia Tornado (IDS) really needs to be a thing! Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 Yeah, in CCIP it was just a feeling as I kept missing compared to where I felt the bomb release was. And as there are a lot of human factors, your aim me be off and such. So, it's hard to show in a track. However, I feel the CCRP results are pretty clear: there is something wrong with the ballistic calculation for the heavier bombs, and it happens in multiple modules, so I guess this thread should perhaps be moved to the DCS general bug forum. Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 Did a final test. F-18 at 500 knots (200 faster than last), 10k feet and Mk-84. The bombs miss by a LOT. So much that I didn't catch their impact in the TGP, even at wide angle. Track added. So, higher speeds makes it much more evident.CCRP at 500 knots - misses by a LOT.trk Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 I just found out to easily test what bombs are doing: use the active pause! 1.) arm your Hornet with 2x Mk82, 2x Mk 83 and 2x Mk84 2.) set unlimited ammo = ON 3.) fly over any ground (you dont need a target) as if you would do to drop any bomb (just make sure you see the impact cross area) 4.) press active pause 5.) drop the bombs (don't mind that the fall line will disappear after last bomb of type was dropped. it'll come back with auto-reaming) You see what the bombs do. You see the spread if you do it 10 times and you see which bomb goes short. You see it better when the bombs don't detonate. (Fuze=off) Link to comment Share on other sites More sharing options...
QuiGon Posted October 22, 2019 Share Posted October 22, 2019 And what's the result of your active pause test? Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit DCS Panavia Tornado (IDS) really needs to be a thing! Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 And what's the result of your active pause test? I knew that this question comes next :) Makes good sense. But I wasn't into the thread's problem and just wanted to offer a method which helps those that care about altitudes, speeds, dive angles, maps etc. All I recognised was the spread. There is no way to come to a conclusion just by dropping 1 or 2 bombs. Am curious too what will be the answer to your question QuiGon. Link to comment Share on other sites More sharing options...
QuiGon Posted October 22, 2019 Share Posted October 22, 2019 All I recognised was the spread. There is no way to come to a conclusion just by dropping 1 or 2 bombs. Well, I dropped 3-4 Mk-84s during a mission a few days ago and they all fell identically and consistently short (about 100m short of the target). That's pretty conclusive for me, especially as I paid extra attention when dropping the latter bombs, to drop them with the pipper exactly on target. Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit DCS Panavia Tornado (IDS) really needs to be a thing! Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 I've tested this quite thoroughly, and the Mk-84 and Mk-83 fall short of the aimpoint every single time. I've made similar drops from multiple altitudes and speeds, and they always fall short. I won't share further track files, as I've already shared quite a few that show the exact same. It is not because of wind or just the inaccuracy of the weapon type, as they constantly miss in only one direction (short of target) I hope this will be looked at, as it makes the heavier bombs quite useless. PS: It wouldn't surprise me if it's a part of a bigger problem that could explain multiple issues that people are having with JDAM and GBUs as well. If the computer drops the bombs too early (way too early if the speed is high enough), then it could cause all kinds of problems, even for precision weaponry. Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 (edited) Well, I dropped 3-4 Mk-84s during a mission a few days ago and they all fell identically and consistently short (about 100m short of the target). That's pretty conclusive for me, especially as I paid extra attention when dropping the latter bombs, to drop them with the pipper exactly on target. ok, I see. you got me doing the test. :smilewink: my conclusion from 20 drops each (PG, 6000ft, 500knts, 32° dive) says that it seems all bombs tend to go short. the heavier the shorter. Mk82 is almost precise. Mk84 is worse. I can not quite confirm your 100m deviation but I see a constant deviaton with Mk84 of 50m. May be higher with other dropping conditions (altitude, speed?). So there is an Issue imho. EDIT: @QuiGon: yes, you are right, I can reproduce your 100m short commings now. Edited October 22, 2019 by Tom Kazansky Link to comment Share on other sites More sharing options...
yngvef Posted October 22, 2019 Author Share Posted October 22, 2019 Thanks for adding to the testing guys. It can only help ED to have as much information as possible! :) Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 (edited) There is something to add. While in Active pause: When you change the bomb from Mk82 to Mk83 to Mk84 the impact cross at the end of the CCIP falling line gets a bit "up" (=the line gets shorter). But the true impact of the bomb stays. So if the impact cross of an Mk84 would not change (vs that of the Mk82), the impact and the cross would be much closer. Means less deviation. My conclusion now is: all three types of bombs share the same impact point (area) but the cue is shorter the heavier the bomb is. So if there was no difference between the falling lines, you would hit the target with a Mk82, Mk83 and even with a Mk84. Question: can this be real? All bombs follow the same trajectory (impact wise)? EDIT: Physics say: with no air (vacuum) it is like that, but we have air. Edited October 22, 2019 by Tom Kazansky Link to comment Share on other sites More sharing options...
QuiGon Posted October 22, 2019 Share Posted October 22, 2019 So all bomb types (Mk-82,Mk-83,Mk-84) have the exact same trajectory, but the projected CCIP (Continiously Computed Impact Point) at the end of the bomb fall line changes? That would explain why the bigger bombs come short, while the Mk-82 hits on point. So either the CCIP projection is wrong or the trajectory and since we have air I would assume the latter is wrong. Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit DCS Panavia Tornado (IDS) really needs to be a thing! Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 So all bomb types (Mk-82,Mk-83,Mk-84) have the exact same trajectory, but the projected CCIP (Continiously Computed Impact Point) at the end of the bomb fall line changes? That would explain why the bigger bombs come short, while the Mk-82 hits on point. So either the CCIP projection is wrong or the trajectory and since we have air I would assume the latter is wrong. i see it that way. (so schaut's aus) Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 (edited) here is a screenshot of the impacts (close to an indestructable car) my Hornet is to the left, so all bombs are short. --- EDIT: to clarify: if I had been using the CCIP-cross of the Mk84 all bombs would have impacted way shorter! I used the Mk82-line. the small craters are Mk82 (fuze=off) the big ones are Mk84 (fuze=off) all dropped from same postion, same altitude, same speed while in active pause. my conclusion: impact area is the same! but CCIP impact cross was not (for Mk84)! (I used the Mk82 cross at start of active pause) Edited October 22, 2019 by Tom Kazansky Link to comment Share on other sites More sharing options...
Tom Kazansky Posted October 22, 2019 Share Posted October 22, 2019 this small distance of (all) bombs coming short, with the Mk82 CCIP-cross right on the target, may be a concession to the small latency between eye and trigger-finger while moving in real time. I tested while in active pause. So I'm not saying that the Mk82 should go longer, too. Just saying that all 3 tested types of bombs would hit if they all had the Mk82-CCIP. Link to comment Share on other sites More sharing options...
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