Fox One

You’re in big error here. AL-31F 12,500 Kgf thrust (that is bench thrust as everybody knows) won’t be the same with the engine installed in the fighter, not even at zero speed. There will be thrust losses caused by the air intakes ducts, and these are considerable. Let’s suppose that air intakes-caused thrust losses for Su-27 are similar (as fraction of bench thrust) with the air intakes of MiG-25 :) Watch in the MiG-25RB practical aerodynamics manual, page 79 – it’s the air intakes-caused thrust losses. You can see, even at zero speed the thrust losses are as high as 26%! Watch at low speeds the lower curve – this shows how because the lower lip of the air intake is down (compared to “lip up” curve above) it decreses the thrust losses (by inhibiting turbulence forming that will lead to pressure losses in the intake ducts, and finally thrust losses). The lip will decrease thrust losses with more than 8%. Air intakes-caused thrust losses is a big deal indeed, somewhere in the manual it is said that if the plane is heavy (or is flying with only one engine) during landing approach and the pilot for whatever reason has to abort landing, and will power up but will have little excess thrust, to not forget that when will retract landing gear the lip will also go up and will decrease a bit the thrust, so is better to retract gear when higher-faster-safer. Also in the graph you can see how the bench thrust is almost reached at high subsonic speeds, and the way inlets starts producing thrust at high Mach. In the same book, page 63, R-15B-300 thrust, military 7,500, max AB 11,200. So we have 15,000 and 22,400. On page 267, in the text – takeoff thrust military 12,200, max AB 17,600. So the average takeoff thrust is 81% of bench thrust in military and 78% in max AB. In LockOn takeoff performance for supersonic a/c is already outstanding, no need to increase thrust here. The thrust is low only at high altitude. In MiG-29 manual it says AB takeoff will take 7-8 seconds. I think you can do that easily in LockOn. MiG-23ML/UB practical aerodynamics manual, page 345. Takeoff forces distribution. It is in that manual, R-35-300 engine is 13,000 Kgf thrust. All you can count in the graph at zero speed is 10,500. That is 80% of bench thrust. Coincidence? No. It is SAFE to assume that in takeoff condition supersonic fighter a/c have about 80% of the bench thrust. So the Su-27 will have about 20 tons takeoff thrust. There are also ejector nozzle flaps losses (airframe-mounted on MiG-23). Anybody not convinced yet is invited to have a more in-depth lecture of those two books, air intakes chapters.

First hello to everybody, this is my first intervention here. From the beginning I want to say judging by the released screenshots and videos that I really appreciate what ED team is doing and the way Black Shark promises to be. There’s no doubt that it will be by far the most advanced and realistic flight sim available to the public in every respect, flight dynamics, avionics, everything and I’m really looking forward to fly it, just as everybody. But I’m more like a fixed-wing aircraft enthusiast, and no doubt MiG-29 and Su-27 enthusiasts aren’t a minority. So we will have Ka-50 with ultra advanced flight dynamics and all the gadgets in the cockpit, but will be left with this caricature Fulcrum and Flanker nav system? Many improvements were done to the weapons systems and I appreciate that, Russian radars starts to look more like the real ones. Sure, there’s a lot still to be done. But I find quite incredible that the nav system is almost the same as in Flanker 2 – 2.5. In MiG-29 the Horizontal Situation Indicator doesn’t work like the real one in ROUTE (MARSh) regime even today, after so many years! On the HSI the wide needle (not the yellow one) should point out to the next PPM. Now there are flight manuals available, there’s also that Su-27SK flight manual, everything can be easily checked by anybody. In real Su-27 the HSI instrument is not PNP-72-12 (was in some early serial Su-27 with early-type “sting” with only 24 chaff/flare ), it is a PNP-72-16 with an additional index and the way is interpreted in nav regime is different from the MiG-29. I’m convinced ED team know very well all of this, but please, will we have to wait until we’re old to have not-so-sophisticated things like that implemented? Please, give us avionics improvements for Su-25,-27 and MiG-29 while we’re still young :) Even to this day in RETURN (VOZV) regime the correct nav indication isn’t implemented. It should show the path to enter in the point of tangency at the 5 Km radius circle, etc like in the picture below. Also the director indication in the vertical plane in RETURN regime isn’t correct. Probably the developers will say this is not a priority, they don’t have the time to fix it. Yes, and building tanks and all kinds of ground nonsense is a priority! I don’t like flying Su-25T. Maybe its flight model is very realistic, don’t know, don’t have the flight manual, but the standard Su-25 is vastly superior in performance and I really enjoy it. Sure, there are some issues, like the huge efficiency of the drag chute, I mean the speed drops from 200 to 100 in under 4 seconds, does anyone on earth think this is realistic? But is nothing that can’t be fixed. The Su-25T without any stores flies like a Su-25 with 6 FAB-500, so I prefer to fly the standard Frogfoot. But on the RSBN-6S nav system there isn’t any functional light-button, to be able to know what waypoint is selected, what airfield. Is that really so hard to implement? The Su-25T already has variometer on the HUD. It will be really so difficult to have that also on Su-27 in all nav regimes? Forget about angle of attack on real Su-27 HUD for take off and landing, but please could we at least have the variometer? Also in landing regime when instrument approach is done and variometer indeed appears, the pitch angle shouldn’t disappear! I have noticed work is being done to new Su-25, -27 and MiG-29 exterior models, and they all look just beautiful, those planes will get what they deserve. But if the avionics and flight models will remain the same, this will have almost no value. My question to ED developers. I understood that in BS the flight models for existing a/c will remain the same. What about avionics? Any improvements? Are there any plans for future implementation of AFM for MiG-29 or Su-27? Probably some questions were already answered in the past so I appologise for asking again. Please don’t get me wrong. I respect ED team. I just want better fixed-wing a/c, like many other enthusiasts. I appologise for the length. Thank you for reading