Fox One

https://youtu.be/fDjElbv3TNM?t=36 The video has poor resolution, but is interesting to me because shortly after the beginning of the takeoff run the pilot pulls the stick fully aft. 7.5 sec after the beginning of the takeoff run the nose wheel lifts; 3 sec later the aircraft lifts off. In the real flight manual the takeoff speed with full AB is given as 230-250 Km/h. An elementary calculation shows that in the video at nose wheel liftoff the speed is easily north of 150 Km/h, and that’s a very conservative estimation. An element clearly visible – during rotation the stick is quickly brought to a position close to neutral (stabilator close to neutral) then just 1.5 sec after nose wheel liftoff the “second stick pull” is clearly observed – meaning the speed has exceeded 200 Km/h, the axial air intakes have opened producing a nose-down pitch moment so a stick pull is necessary to maintain pitch angle. This strongly suggest a nose wheel liftoff speed in the 170-180 Km/h range. The fact that is a two seater doesn’t matter. The two seater has an empty weigth 85 Kg less than a 9-12 single seater, that’s completely negligible. In track “takeoff MiG-29-2” I try to recreate the takeoff from the video. The nose wheel lifts at a comical speed: 80Km/h. Then despite the small speed the aircraft has so much ”desire” to rotate that, to avoid scraping the nozzles on the runway I have to actually push the stick to not allow the pitch rate to increase too much. I even reach a FULL PUSH and I still overshoot slightly my target pitch angle of 10deg. From the beginning of the takeoff run until the nose wheel lifts there’s just 4 seconds … So here is the most direct comparison: at 123 Km/h I am almost at the end of rotation with stick FULLY PUSHED, while the real aircraft with full aft stick only lifts off nose wheel at more than 150 Km/h, and during rotation there is definitely no stick push observed … If you believe that in simulator that’s just a very specific weirdness that only manifests if the stick is pulled fully aft at takeoff, then you’re wrong. In track “takeoff MiG-29-1” at the beginning of the takeoff run I pull the stick just about 1/3 of its total travel. The nose wheel lifts at about 120 Km/h, still much slower than the speed at which the nose wheel lifts off in the real aircraft with stick fully aft! In conclusion, in simulator it is possible to lift the nose wheel at completely unrealistic speeds. takeoff MiG-29-2.trk takeoff MiG-29-1.trk

As is known, at the AOA where the leading edge flaps are lowered, the differential stabilator is switched off. Above 18 deg AOA the aileron deflection angle starts to decrease and at max AOA it is only +/-5 deg. So at max AOA the only control surfaces generating roll is +/-5 deg ailerons. The result – at high AOA you move the stick laterally and nothing happens. Of course, the real aircraft has aileron-rudder interconnect. See attached pages from flight manual. How could an aircraft of this kind NOT have aileron-rudder interconnect? Even the MiG-23 has an implementation of lateral stick-to-rudder interconnect. The ARM-150 actuator in the rudder channel has an authority of +/-8 deg. I’m curious what the developers think this +/-8 deg is “reserved” for. At any stick input, no matter the AOA, the automatics in the rudder channel do nothing to help you. The rudders don’t deflect at all; they just sit there dead. The only way you can “convince” the automatics in the rudder channel to show you they’re not dead is to press a rudder pedal fully, then release it. The quite substantial yaw rate generated the rudders will try to counter by an anemic 1 deg or so deflection.

In simulator leading edge and trailing edge flaps lower simultaneously. In video, leading edge flaps lower in about 1sec, trailing edge flaps in about 2.5sec https://youtu.be/6uy0BdmL-Eo?t=99

In the image is a scan from real FKP-EU gun camera film. This in the only search mode where the line at the right edge of display area also appears on HUD. This is from 9-12A aircraft. https://www.flickr.com/photos/187848316@N03/54804728234/in/album-72177720329192972

In the image is a scan from real FKP-EU gun camera film. As can be seen, when the range scale changes from 25 Km to 10 Km, the Rmax1 mark doesn’t just disappear. It remains at the top of the range scale. This is from 9-12A aircraft. https://www.flickr.com/photos/187848316@N03/54804727989/in/album-72177720329192972

In the attached track, with the aircraft trimmed for horizontal flight at 300kts I perform two fast rolls (@0m53s). The high lift devices were selected off, so that the configuration of the aircraft would remain constant during rolls (anyway with high lift devices set to auto the results are nearly identical ). To avoid inadvertently applying a small pitch input during rolls, for this test the pitch was disconnected from the stick. Pitch before rolls was controlled with trim. The initial AOA before the rolls was 4.3 deg. During the first roll, the AOA at first decreased slightly then increased to 11.6 deg at the end of the first roll. During the second roll the AOA continued to increase to 14.2 deg (after about 45 deg roll) then decreased to a minimum of 5.6 deg, then started to increase again with 14.5 deg at the end of the second roll, generating 3.3G . My question to developers: isn’t the increase in AOA during rolls of up to 14 deg too much? 2 fast rolls.trk

I have performed again the test described in the post above using the latest version of the sim, track attached. I don’t think I see an improvement. In the video, when the roll ends the ball on the artificial horizon was displaced about one diameter. From the moment when the roll ends it takes the ball only half a second to be centered again. In simulator, when roll ends the ball goes FULL left, then FULL right, then center. From the moment the roll ends it takes the ball 3 seconds until is centered again!!! The nose still yaws at huge angles until the yawing motion stops. The sim and the video still are night and day. I am sure the real aircraft doesn’t yaw so badly after a roll in identical conditions, even with the rudder damper switch off. Such an aircraft would not have been accepted for operational service, even half a century ago. This is the only aircraft in DCS that during a roll the longitudinal axis of the aircraft rotates on a large cone, it looks shocking even in cockpit view. This is the only aircraft in DCS that, after a fast roll can’t be stopped precisely where you want, the controllability is way too imprecise. This is the only aircraft in DCS that, after a roll it takes 3 seconds for the resulting chaos to fully die down. Awesome “handling qualities” for an aircraft with a pretty sophisticated flight control system This simulation has been in EA for over a year now. It should be by now in a pretty well polished state. It is not. IMO this FM is still not ready for EA. It is still in a way too rudimentary state. Personally I regret very much buying this module. In my mind I have very greatly overestimated the developer’s competence. I was naive. test1.trk

The upper end of the AOA bracket corresponds to 10 deg AOA instead of 11, track attached. 16-1.trk

@ SOLIDKREATE IndiaFoxtEcho made a poll about aircraft they would like to make for DCS https://forum.dcs.world/topic/308903-what-is-the-aircraft-you-would-like-to-fly-on-dcs-world/ Currently the F-105 is leading...

Here is a knife edge flight without altitude loss: As can be clearly seen from the video, to maintain horizontal flight in knife edge at this alt/speed the pilot must create a beta angle of approximately 10 deg. I have tried in simulator the maneuver in similar alt/speed conditions. Pressing the rudder pedal fully, the beta angle that can be generated in no more than about 5 deg. The lift produced is insufficient and altitude is quickly lost.

On EZ 42 gunsight range scale (screenshot attached) there is a range marking at 600, then another range mark, then... 100. Am I correct to assume the range mark between 600 and 100 corresponds to 350m ? On a serious note, instead of 100 actually there should be 400, as this picture clearly shows https://airandspace.si.edu/collection-media/NASM-A19601563000cp01 Then of course range marks for 300, 200, 100 Currently there is no way to know the inputted range in the 600 - 100m interval that is the most important. Also on the picture of the real gunsight, there are markings for 1000, 800 and 600m with lines between them at half distance, so between 1000 and 600m there are 5 markings. In DCS there are only 4...

In the video already posted in this thread @14m18s the pilot performs an Immelmann followed by a roll and a half during descent I have tried to recreate this using the latest version, track attached. What actually interests me here is the roll. In the video pilot initiates roll at about 130kts, notice how the ball on artificial horizon moves just a little to the right. In my track the ball moves a little left, then hard right, then a little left, then hard right where it remains. I will now compare the last 360 deg of roll, the established roll. The aircraft speed in my track at the beginning and at the end of this roll corresponds pretty well with the video. Roll duration too. Notice in the video how during the roll a point on the ground right in front of the aircraft – the intersection of taxiway to the runway – rotates in a quite small circle. This shows that during the roll the aircraft has a low beta angle, it is almost “pointed”. Now look at my track, watch the aircraft in external view from behind. The aircraft’s longitudinal axis rotates on a cone with a quite substantial tip angle. This happens because during the roll the aircraft has a large beta angle, probably in excess of 10 deg. Because of this, between the start of this established roll and the end of it the aircraft changes its heading with an astonishing 18 deg angle. If the aircraft had a modern HUD, during the roll the velocity vector would leave the HUD sideways. In the video, when the roll ends the nose remains where it was. There is an almost imperceptible yaw oscillation of one or two deg. In my track, because during the roll the flight control system deflects the rudder a lot trying to fight yaw rate/ adverse yaw, when the roll ends the nose goes left 37 deg, then right 11 deg, then left again 6 deg. All the people in this thread already noticed long ago what I described here. Is the developer's official position that actually everything is fine? test2.trk

Comparing the nearly perfect profile picture of the B model posted above by MetalRhino with DCS model, IMO the accuracy of the front cockpit canopy and the transparent part between cockpits leaves something to be desired. Also the angle of windshield arch appears slightly off.

Please see the attached screenshot - between cockpit accelerometer and info bar there is a difference of about 1G.

@ Scandfox Here is a video of an F-16C landing and aerobraking down to about 75kts I would be surprised if the real Mirage 2000 can't hold the nose up even to a lower speed...

Same problem here, same message at the end of install. Also during module installation antivirus showed this message 4 times:

Here is another very short look at the real radar display: There is clearly a lot of room for improvement for the clutter, but Aerges are probably well aware of this.

Phantom, LOL :megalol: The Phantom is "eagerly awaited" by a small minority. The vast majority would be DEEPLY DISAPPOINTED if the new "hot" module from ED is gonna be any old aircraft. Personally I would also be very surprised if it's a "full module" of an existing FC3 aircraft like F-15C. Here is what Matt Wagner said in October 2019 "Is there hope for an F-4 Phantom? If so, would it be off the mark wishing that the developer is Heatblur using the multi-crew experience and technology created building the Tomcat? The Phantom is such a legendary aircraft that we will certainly simulate it. For now, we already have another aircraft (an eagerly awaited one) to work on after the Viper." https://www.mudspike.com/mudspike-ama-with-eagle-dynamics-senior-producer-matt-wagner/ IMHO it is clearly implied it's an aircraft, not helicopter. After reading this forum for more than 15 years, I'm convinced the majority are eagerly awaiting the newest and bestest. Rafale, Typhoon, Su-35 - that's the kind of aircraft the majority are eagerly awaiting. I say it's Rafale

Thank you for giving exactly the answer I was expecting :D In my second track (test2a) where I land with 30% fuel when the speed is 135kts and the inverted T is perfectly on the horizon line, the longitudinal G is -0.45. In the real aircraft in the video it is -0.15 In simulator, if you lower the nose gear to the runway, at 135kts the longitudinal G is -0.1 This deceleration is of course caused by aerodynamic drag and wheels drag. But I am generous and let's pretend the aerodynamic drag is zero and this -0.1 is entirely wheel drag. If you remove this -0.1 from the deceleration of -0.45 that is recorded at 135kts, you still have a deceleration of -0.35 that is more than double the value from the real aircraft. And all of this is ignoring the fact that when the real aircraft is aerobraking at 135kts at 13 deg AOA most of the aircraft weight is still supported by wing lift. Therefore, the load on the main wheels is fairly low and so the wheel drag is quite low. But I was being generous again... I am sorry to say, but it looks like I am wasting my time trying to tell you anything. You have decided in your mind that the simulator is accurate and you will fight to death anyone who sais otherwise.

At the end of the video the pilot lands and performs aerobraking. As can be seen, the speed is decreasing very very slowly. Deceleration from 140 to 110 kts takes about 12.5 seconds. During this time the longitudinal G is between -0.15 and -0.13. Let's see how the simulator compares to that. In the attached tracks I deliberately land at high speed, so that when the speed drops to 140 kts I am already stabilized with the inverted T on the horizon line (or close to) and the engine is already in idle. In track 1a I land with 100% fuel and deceleration from 140 to 110 kts takes 5.3 seconds. That is 2.35 times less than it takes for the real aircraft in the video. Longitudinal G is, as expected, more than double the value from the real aircraft. In track 2a I land with 30% fuel and deceleration from 140 to 110 kts takes 4.6 seconds. That is 2.71 times less than it takes for the real aircraft in the video. Longitudinal G is, as expected, more than double the value from the real aircraft. The aircraft in simulator decelerates so fast not because the wheel drag is too high or the engine idle thrust is too low (although the wheel drag might be slightly too high). These are relatively minor forces compared to airframe drag. It decelerates so fast because of aerodynamic drag that is way waaaaay too high. This is obvious when the nose wheel is lowered to the runway - the longitudinal G decreases proportionally with lowering of the AOA. When aerobraking at 13 deg AOA and there is still enough speed, if you increase the AOA by as little as 1-1.5deg (not demonstrated in the video, but anyone can try) the longitudinal G raises to the amusing value of about -0.5 (for comparison, during takeoff with 100% fuel and no stores, the longitudinal G is about 0.68 ). This test for deceleration during aerobraking is not revealing some minor unimportant inaccuracy that manifests itself only on aerobraking and everything else is fine. Is the same very high drag at an AOA of 13 deg also acting during flight? You bet it is!!! Now if you go back to post #34 and read about the turning test described there, you will understand perfectly why the DCS M2000C results are in a completely different league from the other planes tested F-18 and F-16 (result for F-15 test too, in post #38 ). I performed a perfectly horizontal slow speed flight test with the M2000C (no track attached). For an AOA of 29 deg the speed was 92 kts and the required engine rpm was 88%. IMO the numbers are not bad. I also think the drag at a low AOA of 2-3 deg is generally adequate. In conclusion. The drag at low AOA is OK. Then increasing the AOA the drag gets too high and at some mid-range AOA, drag is way too high. You don't have to be a mathematician to see from the aerobraking test that at 13 deg AOA the drag is not off by some 10%. It is much much more. Increasing further the AOA from this mid-range AOA, the difference in drag between simulator and real aircraft definitely gets smaller and at max AOA of 29 deg drag is, let's say credible. I don't care how the M2000C simulator compares with a turn performance diagram that you know very well it is an estimation. All I care about are demonstrable facts. The drag being much too high at an AOA of 13 deg is a demonstrable fact. Even if that well known turn performance diagram was from the real Mirage 2000C flight manual, and the simulator aircraft would perform exactly like that, that still wouldn't change the fact that at an AOA of 13 deg the drag in simulator is much too high. If the real aircraft in a sustained turn where the AOA is 13 deg (at whatever speed that might be) performes similarly with DCS M2000C simulator, this means in simulator besides the drag at 13 deg AOA being too high, the thrust is also too high. test1a.trk test2a.trk

It doesn't generates more drag at "low speeds". It generates much much more drag at an AOA of 10 to 12 deg. I don't know what the idle thrust of Mirage 2000 engine is and I bet you also don't know. Two examples. MiG-29 engine RD-33 has an static idle thrust of 180Kgf (source, flight manual). Su-27 engine AL-31F has an static idle thrust of 250Kgf (source, technical description manual). Let's put Mirage's engine idle thrust somewhere in between, let's say 200Kgf. At 300kts and 10deg AOA, Mirage 2000's total drag is of SEVERAL TONS. 200Kgf of idle thrust is not gonna make much of a difference. Besides, you don't know (and I don't know) how Mirage's engine idle thrust changes with flight conditions. For example, in MiG-29's case the static idle thrust value quickly decreases with speed and at a low M number of about 0.16-0.17 it is zero, then increasing the speed further it gets a negative value of about -270Kgf at an M number of about 0.57 (source, MiG-29 practical aerodynamics manual). So in the test I made here, in the 300-150kts speed range, Mirage's engine idle thrust might be small positive, might be small negative. But anyway it is negligibly small compared with the drag. So please keep the idle thrust out of this discussion as this doesn't have a considerable effect.

The please repeat the test on your own if you can fly much smoother/precise, and post the track here. Let's see if you will get vastly different results.

What happens, as I don't have the Viggen module?

I just did some tests, tracks attached. With the M2000, F-18 and F-16, with 50% fuel, standard conditions, altitude 1500ft, I perform horizontal flight with 150kts speed. The M2000 needs an AOA of 12.6 deg The F-18 needs an AOA of 11 deg The F-16 needs an AOA of 14 deg How does this fits with your theory? In my opinion, you are generally right. However if that's the case (like the M2000 AOA in the test is 1.6 deg higher than on F-18 ) the difference is small. If the difference was big they would have designed the Mirage in a different way ;) test2000.trk test18.trk test16.trk

The Mirage lands with 14 deg AOA because it can't afford to deflect down 45 deg the ENTIRE trailing edge control surfaces like the Hornet does. It is basically like a plane that lands with "flaps up", and the 14 deg AOA approach is to keep the speed in a reasonably low range. Try to land the Hornet with flaps UP and 8.1 deg AOA on approach and see what kind of speeds you get... You truly don't understand at all the turn test and its purpose. The purpose of the test is to see how quickly the speed decreases from 300 to 150 kts if the engine is in idle (almost zero thrust contribution). This removes engine thrust from the equation and shows only the airframe efficiency. The turn itself is performed to KEEP THE ALTITUDE CONSTANT. If the altitude was not constant the speed would decrease faster or slower if the aircraft was climbing or descending, and this would make analysis and comparison more complicated. The altitude of the test is what you see on the HUD and is held constant. The G or bank angle of the turn doesn't matter. It is what it is. What is held constant is the altitude and AOA. So the test shows how quickly the aircraft at a constant altitude and close to constant (10 to 12 deg AOA) will decelerate from 300 to 150 kts with no thrust. The result is compared as the deg the aircraft is able to turn. It could have been time very well. One aircraft performs much much worse than all the others. Which is obviously not plausible.