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Guest wiwa

Creating a tool for realistic supersonic behaviour!?

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Guest wiwa

Hello,I like flying MSFS 2004 and fsx with the military add ons. But it seems those are the hardest to model realistic. MSFS, after all those years, still isn't ment to fly with military aircraft. One very obvious thing is that a lot of them are to powerfull. They accellerate way to fast and the thing that bothers me the most is their capability to fly max speed (mach 2) at sea level! I've even read reviews that state it is fun to fly trough valley's at mach 2! Well, it might be fun but incredible unrealistic! A lot of the fastest fighters in real life can't fly faster then mach 1.2 at sea level. It is above 35000 ft that they can fly mach 2+.So to fly such planes realistic in MSFS you have to fly with cutback throttle. An incredible immersion killer for me. I think it has something to do with the badly moddeled supersonic region in FS. Because the planes slides through the sound barrier and keeps accellerating untill...? Only the VRS F 18 E/F Superbug has done this brilliant. So it is possible (there goes the 'due to FS limitation' excuse)! All the others, even those who claim 'highly detailed flightmodel' have these unrealistic behaviour. And that's a shame because there are some nice planes out there (Cloud 9 f104/f4, captain sim, Alpha sim...) but suffer from this unrealistic aspect. Maybe it has to do with eye candy or with the fact that the majority of MSFS fans fly subsonic, civilian planes. Although the supersonic Concorde suffers from the same thing. But I couldn't believe the fact that something like that, so unrealistic, so obvious, has been neglected. I almost never see any topic concerning this unrealistic feature. Am I the only one?! That can't be. Maybe all the others are kept away because of this? Or the majority are used to this feature and accept this as a standard or worse.. realistic?Now my question? Is there any tool that can fix this? A tool that works for all existing planes. A tool that makes fly your plane mach 1.2 at 0 ft and fly mach 2 at 35000 ft. Maybe a tool where you can insert the values for max speed at sea level and max speed at 35000 ft. Then it keeps your plane within these limits. To make it easy, just a linear calculator. So when you put in the following values: Mach 1.2 at sea level (0 ft), Mach 2 at 35000 ft. It automatic calculates a speed of mach 1.6 at 17500 ft. If it is to hard to do this within the true design of the model (drag/engine/power), maybe it can be done with an automatic throttle feature. The throttle cuts back automatic (or the engine power) when the max attainable speed at the specific height is reached. Ofcourse not as realistic but an option that can work to make the speed ranges realistic.Besides this I wonder if something could be done at the spool up times of the engines. Some engines of some military fighters for MSFS spool up together with throttle movement (0,003 seconds!). In real life, engines take 2 to 13+ seconds to go from idle to full power. Maybe something to do about that?I wonder if there are any clever minds that bother to make something for this. Would take the military or the supersonic aspect of MSFS to a new level!Greetings,Wiwa

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Hi,understand what you are saying. Working myselfe on a F18 panel and know this behaviour of the model. I think a gauge should do it ( not a tool) what you are looking for. Let me have a look into it. Need it anyway for my stuff. RegardsDietmar

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WIWAhere are my findings regarding speed control on a supersonic aircraft. For my testing I used the F-18 E/F model from "Team FS KBT" (can be downloaded from AVSIM).First test : Speed control by using AP autothrottle up to 2.2 mach as the max..By adjusting the following parameter settings in the aircraft.cfg :[TurbineEngineData]fuel_flow_gain=0.006 //Gain on fuel flowstatic_thrust=17500.000000 //Lbs, max rated static thrust at Sea LevelThrustSpecificFuelConsumption =0.81 //Thrust specific fuel consumption (Jets)AfterBurnThrustSpecificFuelConsumption =1.5 //TSFC with afterburnerFuel flow and static_thrust are the most important parameter.As next the setting for :[jet_engine]thrust_scalar = 1.49Depending on your model, you need to adjust this settings accordingly. The setting above controlled the speed of my F18 model about 1.2 mach at sea level and and increased the speed step by step depending on the altitude up to 2.2 mach max at about 32,000 ft.This follows the specs of the aircraft.Again: Results are under control of the autothrottle !!!!!!Second test, but now under manual control , means , shift throttle lever up to max .Now you need a little gauge to in order to control the limits. The following logic controls the speed up to 2.2 mach max by using the fuel flow variable:(A:TURB ENG FUEL FLOW PPH:1,pph) 7000 > (A:TURB ENG FUEL FLOW PPH:2,pph) 7000 > (A:GEAR TOTAL PCT EXTENDED,percent) 1 < && && if{ (>K:THROTTLE_DECR_SMALL) }and this logic to control the speed also below 20,000 ft: (A:GENERAL ENG1 THROTTLE LEVER POSITION,percent) 65 > (A:INDICATED ALTITUDE,feet) 20000 < && if{ (>K:THROTTLE_DECR) }Finally, in order to stop acceleration above 2.2 mach I used this logic:(A:AIRSPEED MACH,mach) 2.1 == if{ (>K:THROTTLE_DECR_SMALL) }After this implementation the speed control works in both modes ( autothrottle or manual ) the way it should be.I do not believe on a general tool/gauge for all supersonic models. You need always adapt the parameter in your aircraft.cfg accordingly and on top possibly a gauge addon.Normally the developer of the model should take care of the flight characteristics of their model. However if not, the user must take care of it, or take the model as is.I hope, my findings where helpful for you.Dietmar

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