Maverick Su-35S

Sorry if I'm starting this thread and a similar one is already there, but I'd rather make this subject fresh as it regards new FM updates done to the MIG-21. In the latest version, the MIG-21's FM won't allow for an angle of attack greater than 15 before the stall onset. Initially the critical angle of attack was fine and very appropriate for this type of wing at about 20 degrees even if it doesn't have leading edge droops. For the low aspect it has and high sweep, 20 deg. of AoA was quite fair. I personally can't understand why a decision was taken to lower the critical AoA to about 14-15 degrees, which is even lower than that of the L-39 (16..17AoA) for instance, or than the A-10 (which has 17 to 18.) or Su-25 (17 AoA). I can't get the logic behind this very low value of critical angle of attack for the 21. If is there any wind tunnel or other hard proof which shows that the MIG-21 in clean config (no external stores) with flaps up starts to stall at 14..15 deg AoA I accept that, although it's very non-logic for this to happen. All the best!

Here is the explanation why the AoA vane (which the cockpit AoA tells at what angle in degrees it's deflected) deflects to a higher angle than the one at which the wing's chord meets the air. Let's take this case: The plane is at positive lift and some angle of attack, so the high pressure region is below the aircraft and the low pressure is above it. The air, as any other fluid will always start a motion from high to low pressure. When the air meets the higher pressure of the aircraft, which in this case is the belly of the whole fuselage and wings, it will rapidly start moving through wherever it finds possible towards the low pressure region, which for instance would be the top of the fuselage and wings. In an ideal case, one could imagine some airflow lines that are nothing but continuous straight lines passing around the plane and so the real angle of attack (between the wing's aerodynamic mean chord and oncoming air) would match the angle at which the vane is deflected by the air, but in reality the airflow curves and doesn't hold a straight line as it passes the aircraft and the more difference in pressure the exponentially more the airflow curves. This curvature of airflow lines (if you were to see some smoke lines in a wind tunnel on a plane's fuselage model would be great) around the fuselage of any plane and also around where the AoA vane is mounted will undeniably deflect the AoA vane with them, thus making it show a higher angle than that between the free stream of air and the wings chord. So the higher the real angle of attack and the more intense the differences in pressure between the top and bottom of the plane, the more the airflow curves in an exponential manner (curves more rapidly as real AoA increases) as it tries to run away from high pressure to low pressure deflecting the AoA vane with it. At low real angles of attack, the AoA indication in the cockpit will be very close to it, but as the real AoA increases, the AoA indication grows faster and faster away from the real AoA. Same does for negative AoA. Starting from low negative AoA towards high negative AoA, the onboard indication again grows much faster than the real AoA. For short (cause I always get into thorough details when I discuss something, so the conclusion is at the end), the curvature of airflow around the fuselage as it goes from higher pressure towards low pressure deflects the AoA vane also with it thus making it show a higher angle than that between the air and the wing.

Oh man I'm glad that after so many posts of people that don't quite understand what that 28-30-33 deg.AoA is all about, one managed to see the difference;)! Indeed, the REAL angle of attack is much lower that what the needle in the cockpit points at. The reason is very simple, but again, as people confuse stall speed to critical angle of attack, the same way they confuse the indicated angle which only indicates how many degrees the AoA vane had turned and NOT the real angle of attack at which the wing meets the air.

I'm on the same track with you mate, but we should only hope that Polychop will take the time to re-look into it. We know they are busy and as they've said they worked 3 years at the helo and that it's their 2nd job doing this, so they can't work at it everyday and most probably needed some time to learn flight dynamics and software programming in order to make this all happen. Nobody gets born with knowledge and learning, working and testing cost time and I personally know this well too, but indeed action should take place though, slow but thorough!

Thank you! I don't want to sound arrogant or bad tempered as some may see me losing it very easy, but this is what I'm an aerospace engineer and pilot for..., for the loving of a realistically made flight model, nothing more! Although the flight model is the most painstakingly hard thing to achieve in order to go past 95% realism as other simulators praise with, but with people which have a good knowledge of flight dynamics and aerodynamics in first hand, only modelling and programming remains an effort. Best wishes!:thumbup:

Hi, After reading the following article: https://forums.eagle.ru/attachment.php?attachmentid=145242&d=1469709160, I was very delighted to understand the effects and differences in performance obtained within various changes that the F-5 had benefited of throughout it's design program and I couldn't wait to jump back in the cockpit of this purely lovely DCS product to try and replicate some of that article's results which of course, regard the flight model of the aircraft in DCS. The main reason why I fly in DCS is because the flight models of each aircraft can bring me closer to how would the aircraft behave in a real flight, so the flight model of each aircraft is what I put my money on and my main goal for using flight simulators. Doing missions, shooting, fighting is on 2nd place and anyway..., every game is good at that, but a simulator..., can only be as good as what it can best do. Now, the reason why I start this thread is because, although I've read the article and I acknowledged that ED knows about it, I can't yet find some stall&spin characteristics of the aircraft during it's flight tests. In it's early patches, the F-5 in DCS was prone to depart in yaw at slightly above 20 deg. AoA, which was indeed much lower than what tests showed in the above article including the fact that the real jet proved to be stable in roll-yaw at very high angles of attack of 45 through almost 70 most probable due to the high energy vortex generated by the lerx (leading edge root extension) which improved aileron and rudder effectiveness. Even if in the early patches the F-5 was prematurely departing and possibly had an exaggerate loss of controls effectiveness during spins, the wing rocking effect and pitch oscillations during spin were present and seemed realistic. Now these important effects seem to not be present anymore and I believe that are must! In real life a fighter with lerx indeed finds the pitch-roll oscillations during spins at much higher angles of attack and has an increased tendency to these effects during spins in comparison to a non-lerx airplane. Sometimes, depending on the yaw rate (not too high not too low) the rolling oscillation during a spin becomes so intense that the plane may at some point flip upside-down and vice-versa and this is contributed to the wild variation of the center of pressure between one wing and the other. A remarcable aerodynamic effect indeed. Here are some great examples: https://www.youtube.com/watch?v=AJgflKRbYgY https://www.youtube.com/watch?v=ZpxD6n9ZWyQ https://www.youtube.com/watch?v=xTrLzkA_mCc Is there any way that pitch-roll oscillations may occur again in later patches? A great day and Merry Christmas to everyone!

Totally agree, and it's not the first time when manuals needed rework because they killed people as the data was inaccurate. At higher AoA and higher yaw rates, the lowered the flaps are the worse the spin becomes. Everyone can test this on Su-25s, A-10s or any other plane that a lowered flap will tend to keep you spinning or reduce the chance of lowering the yaw rate in a flatpsin, so it's a true fact that flaps should be zero or negative (gliders have negative flaps) in order to get out or get out quicker.

Because it's very likely that few people know why is the aileron used towards the spin and why should the stick be pulled in general (NOT PUSHED) until the yaw rate gets low enough to offer the desired responsive controls and completely stop the spin, we will discuss how does the aileron increase and/or decrease the local Angle Of Attack on the wing along which the aileron spreads, knowing the consequence that a longer aileron with a higher area also gives a higher desired/non-desired effect. We know that increasing angle of attack we increase both lift and drag and while the lift increases linearly the drag increases exponentially (increases much more). The drag increase due to AoA increase is generally an inconvenient, but not for spins though. Asymmetric drag between the wings and/or rudder lift towards left or right (left or right rudder inputs) is what generally induce a yawing moment which can develop into into a spin at angles of attack higher than stall, while a higher drag generated on both wings combined with rudder input is a great ingredient that helps to get out of the spin or at least decay the yaw rate well enough to lower the AoA up to a level where the controls respond normally. On aerobatic aircraft with high aileron span and surface, getting out of a spin can be easily done even with rudder neutral by just applying full aileron towards the spin, not neutral or opposite. Never use aileron opposite to spin or you could possibly hold your plane (any plane) there forever. Imagine that you are in a rightward high yaw rate spin (above 50 deg./s.) at very high AoA. By applying full right aileron (towards spin), both ailerons will increase the AoA of their wing, not just one. The right aileron rises, but the right wing's AoA along the right aileron will increase instead of decrease because the airflow is now coming from behind (the right wing has negative airspeed or flies backwards so to say). The left aileron lowers and the left wing's AoA along the left aileron increases as long as the airflow is coming from the front, which normally happens. So, when you apply aileron towards the spin, you increase the AoA for both wings and generate higher wings drag which is crucial for reducing the yaw rate which is the greatest enemy in a spin. If you would ever use ailerons opposite to spin, as a rookie might naturally want to, you would only worsen the situation because the AoA on both wings would be lower enough so that the generated drag might become null and the spin becoming non-recoverable. Generally, the rudder input isn't enough of alone and it's the ailerons which in many cases offer a higher desired beneficial yawing moment that reduces the spin. Look at fighter test pilots also on how they use the ailerons to enter and get ouf of a spin, cause they know these effects very well. Here's an example: As you can see, he induces the spin using ailerons opposite to the desired direction of spin and when told to recover he immediately applies full stick towards the spin and the yaw rate already starts reducing. The fact that the F-18 started tumbling upside down when the yaw rate started to decrease is something specific to the F-18 due to it's general aerodynamic configuration, but the aileron towards spin was essential. Great day!;)

Hello, Let me get straight to the subject, and please don't find me offensive, as I'm not, even though pi%##off by what I see when I fly this bird! Did NASA forget to evaluate the gyroscopic and P-factor effects on the rotor in their report? If that's so, it would perfectly explain why the GAZ acts like a space shuttle flying through the vacuum of space. You only induce some pitch/roll accelerations and achieve some maximum angular velocities with the cyclic stick, nothing more, and these accelerations and maximum angular rates don't differ at any flying speeds (IAS or TAS)! A perfect spacecraft. How is this possible? There is NO gyroscopic effect driven by the rotor blades...! Why? Are the blades having 0 (zero) weight? There is NO P-factor (which is purely aerodynamic) simulated either. This explains why the helo keeps a gained pitch and/or roll rate for very long and won't decelerate those gained angular rates as quickly as normally should once the stick is returned to neutral, because the aerodynamic effect being generated on EACH blade is not the correct one. There is just a visual effect of the rotor blades bending under loads during flight, but not a complete aerodynamic effect on each one. The AoA is the angle between the free stream of air and a given airfoil chord (everybody seems to know the definition, but few completely understand it). Remember that a correct aerodynamic effect should take into consideration both the AoA and the beta angles which only together can correctly simulate the effects between the airspeed vector (which seems of concern here) and chord while the airspeed vector may vary quite high (as direction and value, although in a cyclic fashion correlated to the rotor's RPM) as long as there is a relative airspeed higher than zero between the rotor's axis and the free stream of air. The way it is right now demonstrates that not even the AoA alone is being correctly modelled for each blade in flight due to the fact that the airspeed vector's direction that should meet each blade's mean aerodynamic chord depending on rotor rpm, total airspeed relative to the rotor's axis (translational movement) and any angular pitch and/or roll velocities that SHOULD affect the AoA on each blade aren't fully/correctly simulated. Where are these effects which have a huge impact in flight behavior (for helos at least)? I don't have to be a pilot (for quite some years) and aerodynamicist (aerospace engineer) to tell these things! These shuold've already been known. It would've been common sense to just test other DCS (done by Eagle Dynamics not third parties) helicopters to see how in general a helicopter responds in all known situations, because right now, ED are still the best in making authentic simulation of an aircraft's flight behavior (flight model) and it's other systems and so are a benchmark or source in determining if a flight model is accurate enough (modern simulators achieve beyond 95% level of accuracy in FMs) or is still a WIP. The FM is mostly the first thing that you start with (at least that's what I'd do if I were to start my own simulation as I want REALISM and PHYSICS FIRST instead of graphics, electronic systems, etc.) if you want to impress someone and not leave it for last. Don't know how does ED do it, but they do it right with little error. Somewhere in this topic it's said that Polychop had actually talked with RL helo pilots. Don't know if it was just a chat or those pilots actually tested the Gazelle in DCS, but normally they'll all tell that everything that can differ from one helo to another (as well as from one airplane to another) are the values or quantities within the effects, but NOT the effects themselves..., those can't be non-existent and are all governed by the same laws and physical principles. Also, on the other hand, the chopper seems to enter some weird zones of the flight envelope (I don't have it's flight envelope to tell, but I bet that those who have it can look at it and compare it with what the sim does), because in many cases when applying full right and backwards stick for a split moment (to avoid something or just because you want to) and then return to neutral or push full forward and left stick to counter the first inputs the helicopter keeps maintaining a slow rightward roll rate which rarely stops or starts to develop (respond) towards the new stick input, if you haven't already hit the ground. So, in other words if you sharply pull full aft and right stick (no matter how long if beyond 0.5 seconds), the helicopter enters some strange phenomena which keeps it banking right no matter how you'd jerk the stick in order to get out from that situation. You will see this strange effect after the 2nd and further flights from the following posted track: [ATTACH]153910[/ATTACH] Oh, really? Don't get me wrong..., but if you say that "I am very pleased with the way polychop handle the Gaz and how it is modeled", then that's either because you are ignorant to what's going on or you don't yet understand the laws of physics at the level needed to see what's wrong with this helo, cause right now it has little in common comparable to a real life helo. Do you like flying a spaceship or a rotary winged aircraft flying through air? It still needs work on the FM and I bet the guys will do their best to figure out what's going on (even if it might take to review things back from the beginning, regarding the FM alone of course). Let's not feel offended and rather evaluate what's going on before jumping! If there are no hard feelings and we're all looking forward to good results, I wish everyone a Happy Christmas!

The thing is when we talk about realism we deal with numbers (most of the time) and comparisons between simulation and real life, not with subjective forms of explanations. What the topic starter has found shows some possible irregularities within the flight model, not that the Gazelle wouldn't be a good climber or have a good acceleration. If you could compare something with real values it would be much better, otherwise it can be misleading. Good day!

Seems to be a problem from the latest patches. I've deleted the impostors.lua file just to make sure there's nothing wrong with it, then let DCS repair do it's job which put it back in place, restarted the sim, tried different settings for the model enlargement (off, small, large, etc.), then quit the game, restarted, resaved the mission thinking that any changes to the model enlargement might require re-saving the mission in order to take effects. Nothing! The model enlargement feature is completely out of action now and although it wasn't perfect, it's way better with it than without.

It's remarkable that DCS's professional flight model not only take aerodynamic forces and moments as function of AoA and beta, but also with Mach number, covering very realistically the behavior of the real aircraft. The most important changes in lift, drag and moments coefficients for a fighter occur throughout the transonic regime where dramatic changes in aero forces and moments develop between M 0.85 and M 1.0 (as it may be the case for MIG-21) and find a somewhat mirrored recovery towards M 1.2...1.3. Although not shown in that very valuable diagram that you linked, normally from where the critical Mach number starts until Mach 1 is reached, the CL (lift force coef.) starts to constantly drop due to emerging shock stall effects, the CD (drag force coef.) starts an abrupt constant rise and gets about double that of the low Mach incompressible flow which makes it hard to pass through Mach 1, the Cm (pitching moment coef.) constantly goes way more negative and between Mach 1 and Mach 1.2 or 1.3 the variation of these variables is almost a mirror of how they develop between M 0.85 and 1. I agree that there's a difference between a virtual pilot's spring loaded stick and a real MIG-21 in flight hydraulically loaded stick with feel actuators, but even so the difference shouldn't be so great even without force feedback giving these reaction conditions where even a real 21 pilot couldn't hold an alpha between 15 through 20 and vice-versa as he wants no matter how hard he'd try if the plane would react as in DCS like it slightly jumps through those AoA ranges and it would be even more impossible for the real pilot to do that because his stick has a limited maximum travel speed while even us with a virtual and quicker stick can't hold a constant alpha through that AoA range;). So you also agree that there is a problem with the G-load drop after the stall (as I've talked about in my first posts here) which no other plane in DCS does so this is abnormal for to the 21 only. Giving real experimental results, at the bottom of the CL vs AoA function beyond sall, the CL should be somewhere between 60% through 100% of the maximum CL found at the stall point depending on wing aspect ratio (ex: the higher the wing aspect ratio and thinner airfoil, the greater the drop), wing sweep and boundary layer control which is either through vortex generators such as LERX or blown trailing edge devices. Indeed it's always better to use real experimental data as input when you have it, cause that's why we sometimes find weird aircraft behavior in DCS if the aerodynamic forces are only evaluated using virtual wind tunnels. Right..., or any difference should be little anyway but this is mostly for aircraft with less wing sweep and higher AR(aspect ratio). For lower AR and higher sweep as the MIG-21 has, the generated vortexes at the leading edge are significantly strong to reduce the CL drop slope as AoA goes past beyond stall, so not only that it should be somewhat rather symmetrical, but may even not drop that much anyway. I personally believe (just by experience, I didn't stand to make any experiments) that at the bottom of the drop, the G-load should be at least 80% the maximum achieved at stall. As you've said, controllability and static and dynamic stability are not necessarily linked and are mostly individually linked to aerodynamic effects, but it's clear that these effects should be meticulously examined bit by bit for how does the aircraft reacts in accordance with reality when real data is available either if a real test pilot can share it or if experimental data exists. The fact that after newer updates the ailerons no longer give any effect after the plane passes beyond stall AoA, which is indeed a controllability problem while the rudder effect is kind of too great otherwise, is indeed a new aspect to talk about. I'm very glad for these constructive and realism based conversations. Best whishes!

Hi again, Good progress guys, now the 90 deg.AoA stuck behavior has been eliminated and the plane responds like a real one and in the same time the strange and very abrupt pitching moment variations have also been eliminated between the stall AoA and some 10..15 deg. more, thus the pitching moment variation for a constantly held elevator deflection as the aircraft passes through the stall AoA towards the maximum AoA achievable is more gradual and looks quite realistic and also the plane develops some outstanding pitch-roll oscillations in certain conditions during which is unprecedentedly realistic, but still, some other problems emerged though. Just as a review, let's start with the good facts and finish with the newly appeared problems: The fixes: 1. AoA at or near 90 is now fixed; 2. Realistic pitching moment variation between stall AoA and maximum reachable AoA for a constant elevator deflection, as a function of AoA is obtained. 3. Impressive and reality related pitch-roll oscillations during spins according to elevator inputs and existing yaw rates is now achieved. New issues: 1. The rudder effect above stall AoA is quite high. For instance you can induce quite high initial yawing moments during high AoA conditions where most of the rudder would be shadowed by the fuselage and most of the airflow that the rudder would encounter whould most probably be detached/turbulent. During tests, even if you'd allow the mig-21 to gain high yaw rates during flatspins, from the moment you apply full rudder opposite to spin, the plane takes just one or two turns of spin more (which is quite quick) giving the plane's mass and yawing moment of inertia, so either the yawing moment of inertia is low or the yawing moment generated by the rudder is high, but I believe that it is the latter which causes this. 2. Ailerons no longer create yawing and rolling moments above stall AoA. This was perfectly modeled before the mentioned fixes were noticed, but now this shows up. It is known that as the AoA increases from null lift towards 90 deg. of AoA, the yawing moment generated by the rudder has a logarithmic decrease towards 90 and remains very low at that angle, the rolling moment due to ailerons also have a logarithmic decrease towards 90 and while the wing reaches 90 AoA the aileron deflections would produce zero rolling moments, except when a yaw rate exists which could allow for slight rolling moments to develop. Also, as the AoA increases between null lift towards 90 deg., the ailerons deflections produce yawing moment which is known as yaw due to rolling input, and this yawing moment should have a logarithmic increase this time. So as the AoA gets higher you would normally find a lower yawing moment from the rudder input but higher yawing moment from the ailerons, these effects reaching their peak at 90 AoA. For some reason, the ailerons no longer produce any roll and/or yaw as the AoA is higher than stall. 3. The critical AoA of the MIG-21 has suffered an unexplained decrease from around 20 deg. towards 14..15 deg. In reality the critical AoA will always increase as the aspect ratio is lower, as the wing sweep angle is higher and as the airfoil is thicker and has a higher camber and also as leading and trailing edge devices (including boundary layer control systems) exist. During normal flight without any high lift devices engaged, the critical angle of attack increases for two reasons: higher wing sweep and lower aspect ratio. The MIG-21 has both a very low aspect ratio (almost as low as the F-104 has) and a quite highly swept wing. A B-737 airliner finds a stall AoA at about 14..15 deg. when no slats or flaps are out, but the airliner has a high aspect ratio and lower wing sweep than a MIG-21. The F-15C in DCS finds a stall AoA at around 24..25 AoA and although it also doesn't have leading edge devices it has a similar aspect ratio and sweep to the MIG-21's wing, but even if indeed it has a higher aspect ratio and slightly lower wing sweep than the 21, the difference is dramatic now of about 10 deg. The F-15 indeed has some vortexes generated between the engine inlets and the canopy which energize the boundary layer between the wing's root and fuselage, but they are quite weak and may probably increase the critical AoA by 2..3 deg. The MIG-21 should probably regain it's 20+ deg. stall AoA which was correct. Best regards!

Hello, All the vehicles in the sim have personalized engine sounds, rolling sounds, different armament firing sounds, etc.! The problem is that the gun firing sounds (bullets, high caliber shells, missiles, rockets, etc.) are heard at the same amount of intensity or even slightly lower than the engine sound. The amount of decibels given by the gun firing and missile shooting should be a lot higher (maybe 2..3 times higher) than that of the engine running at idle. When will we be able to hear armament shooting sounds much more louder than the surrounding sounds and also from the distance, similar to real life?

The model enlargement idea isn't bad..., it's just that it needs modifications to bring it closer to the real thing. The idea with the 2D model is appreciably good in order to overcome the graphics algorithm that makes every unit (vehicle, aircraft, boat, etc.) disappear prematurely between the pixels at ranges well below those for which the human eye can still clearly see distant objects. The thing with the shader (possibly) and transparency effects are creating different problems for spotting an object, but otherwise I personally agree with ED's idea for the model enlargement effect which kicks in above certain distances. What many have already noticed that needs rework, is the Sun's reflection over the 2D enlarged objects that should normally shine very bright (ex: vehicles, aircraft that fly below the viewer, etc.) and so should be much more easier to spot than those that are against the Sun's rays, but in the game exactly the opposite happens when the 2D model comes up because there is no reflection to be seen and the units blend in with the air, land..., etc, thus making them poorly visible from the Sun's direction. Probably, the non-existing reflection could be affected by the transparency model which already makes the units quite transparent and much harder to see even from the lowest distances since the 2D model appears and even if a value of 0 is given for the alpha exp. effect in the impostors.lua file, the transparency can still be clearly seen even at low ranges ruining everything.

Hi, Did anyone wonder why does the KA-50 have Kh-25ML missiles in real life? Definitely because the Kh-25ML would have a greater distance than the Vikhr missile besides delivering a greater damage. Since some updates (don't remember when) in 1.5.x or 1.2.x, the Kh-25ML missile benefited from an AFM flight model which made it have a realistic flight behavior, but also drastically decreased the range of the missile through excessive drag and much lower lifting performance. If one might check to see, the Kh-25ML in the sim will reach it's critical AoA while flying at 1G when the speed falls below 880km/h IAS (so that is it's stall speed). In the sim, the Vikhr also exhibits stall below 860km/h IAS and it's rather obvious why regarding the very high wing loading it has with hose tiny control surfaces, but the KH-25ML with it's lower wing loading (compared to that of the Vikhr) should logically have a lower stalling speed than 860km/h. The Kh-25ML's weight to drag ratio should be much higher than that of the Vikhr, which would mean that it should also have a lower deceleration than that of a Vikhr when the fuel burns out. There could also be a problem with the pitching/yawing moment of the KH-25ML which is very low as it responds very sluggish in pitch/yaw motions while flying at quite high speeds as Mach 2. The KH-25ML also has a lower top speed than a Vikhr missile which isn't normal. In game, the KH-25ML, can barely go beyond 2000km/h at around 1000 meters, while the Vikhr goes as fast as +2500km/h at same altitude. Because of all these aspects, you can't hit a target with the KH-25ML unless it's closer than 8.5km and your KA-50 isn't lower than 2500 meters AGL if it shoots from a stand still, cause the missile will never reach it's destination. The Vikhr goes well beyond 8km away if you shoot it from 2500 meters AGL in hover, being able to reach and kill targets as far as beyond 12km ahead. I don't believe that the Vikhr is overrated or has exaggerated performances, but the opposite, I believe that the KH-25ML has some deficiencies, being unable to reach a realistic flight performance and range. Here's a track file which should regard all the above: Kh-25ML vs Vikhr range.trk I wish it would be re-checked or tested!

When the MIG-21Bis first appeared, you were able to kill tanks and other small objects quite easily by just pointing the radar beam pipper on them. Where the pipper was locking somewhere on the ground, the missile was going exactly at that point with very high precision, just the same way as someone would use the KH-25ML on the Su-25A with the laser pointer and targeting pipper. Now, after some patches when DCS 1.2 was still on, something went weird and the Grom-66 no longer behaves that way and doesn't go anymore exactly where the pipper points at and also the pipper doesn't lock the ground anymore, but some imaginary point in mid air. I've noticed this by looking down on a target and locking it up, after I went flying lower at about 5..10 meters AGL I saw my pipper float somewhere in mid air above the ground target (the pipper was floating at about 30-50 meters above the ground), so it didn't lock the target but the air instead. This probable pipper bug might explain why does this very important MIG-21 missile go like crazy.

Let's let them fix the model enlargement issues first..., you don't wanna get shut down because you couldn't see your opponent anymore when you should've clearly seen him even as far as 2-3nm away, because by the time you see your enemy, he's most probably behind and seconds away from killing you.

This was important, thanks! It is possibly important to have little difference in the size between the 2 models when transition occurs, so that as the target gets closer or further you should barely notice the difference, otherwise it would look ugly wouldn't it? Hence, the difference between the number of pixels at which the 3D model turns 2D and the number of pixels the 2D model should have (which turns to how big it would look like) should be minimal (0 difference if possible). So I don't know why, for example, a Maxsize of 20 and a Minsize of 8.0 would be a good idea if you see a big difference at the transition between the models.

To be more specific, the "maxsize" is the number of pixels a unit should get to have on a screen in order to transfer the model between the 2 shapes and "minsize" would be the size in pixels that the constant dimension 2D size would get or what is the reference for "size"? The text in the impostors.lua file doesn't tell what "size" actually means. Thanks!

Hi, Hope you guys test enough these values and if you believe they're wrong change them as you want, I'm only a player as you all are and I'm only looking towards realism. I'm no developer, but this is what I find optimum due to some limitations regarding the target's transparency with range. The file is a "virgin" to DCS if you use Windows 10 because Windows 10's notepad somehow corrupts it. Someone told me (about 3 posts ago) that it uses a BOM technique when it saves a file and it seems that it ruins this file and DCS no longer recognizes it when you play, but if you'd download the free Notepad++ and edit the impostors.lua with it instead you can make any changes to those values as many times as you want and the file will have no problems. Good day!

You guys want the best or most optimal values for model enlargement? You got it...! Try replacing the following either for SMALL, MEDIUM or LARGE and use it: maxSize = 8 minSize = 7 alphaExp = 0.58 Although the maxsize and minsize values might be appropriate for creating the transition between the 3D model and the enlargement shape in a way that you'd hardly notice (which is good), the alphaexp which affects the transparency of the model, which DOESN'T increase with range (it would be good if that would happen) but it's rather a constant and it's hard to find a value that allows for seeing both the air and ground units in a realistic manner, because if the transparency is higher in order to not let aircraft be visible from exaggerated distances, the ground units would suffer being too transparent on the ground thus making it more difficult to spot ground units even if it were no model enlargement active and so by trying to give the alphaexp a low enough value to allow ground units to be spotted from realistic ranges now the aircraft could be seen from as far as 70km away, so..., letting it to approx. 0.58 might be the best compromise!

Well, whatever it does it ruins the impostors.lua file on the other way, while notepad++ seems to not do that even if it might not use BOM!:thumbup:

Oh dear..., damn Windows 10:P! With notepad++ the file works and doesn't get corrupted anymore (getting from original 1020 bytes to 1023 bytes) and now I can play with these model enlargement values for a little "fun"! Realism is all we need/want!

Hi "Why485", Can you please confirm me that even with notepad++ if you try to open the impostors.lua file, not modify anything, then simply save it, you won't get a different file size than the original after saving it? The original file has exactly 1020 bytes, but after I save it (without touching anything) with Windows 10's default notepad, the file becomes 1023 bytes in size for no reason and the sim doesn't recognize it anymore..., strange why I'm the only one having this issue! Thanks;)!