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Guest wiwa

Tool for realitsic supersonic behaviour at all altitudes?

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Guest wiwa

Hello (also posted at the 'add on developers forum'),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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Its not that hard, but needs some understanding, and lots of time of Flight Dynamics Editing.Remember, it CAN be done.Check here: http://perso.orange.fr/hsors/index.htmlThere are tables in the .air file what you can adjust, and really make it as you want it, with or without real world data. But its a bit of black art, I did it in the very past for PSS, and when you finally get into it, its getting easier.And today, a lot is more known about it then it was in the old days,Johan.

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Guest wiwa

Hi Johan,Thanks for your reply. I will get into that. I did a lot of tweaking with the cfg files some time ago for various planes. But it was not easy to get it to work on all altitudes. I adapted the drag scaler. But I ended with planes that flew mach 1.1 at sea level but couldn't get any faster at higher altitudes. I also changed roll rates etc with various succes.My knolledge about CFG editing was not sufficiant to get me the results I wanted. But maybe with the help from your post...I will have a closer look at this as soon as I have the time,thanks!Wiwa

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Guest napamule

Wiwa,You want auto speed WITHOUT auto throttle? That is what is sounds like. You want to 'floor' the accelerator, and leave it there (yet it not take 'effect' until 13 seconds later if stoped), yet be able to 'automatically' (somehow) limit max speed depending entirely on altitude (and not on throttle or power setting)? What Sim do you want to use this in? And the engines are Ion Emmiters, or what? Phased Lock Loop Hydrogen Compression Rockets?You are right in thinking it would take a 'gauge' (XML) to do this. Maybe possible, maybe not (ask RCB). I don't do XML gauges. I doubt any section of Air file is capable of being made to do this 'governor' type operations (yes, plural). One would think that with pilot input when using AP and Auto Throttle and/or Auto Speed, that that would be sufficient. Unless your panel did not have a throttle lever, speed (or Mach) gauge, or altitude gauges you could read.So no matter what aircraft you were flying today, they would all exibit the same speed, and rate of climb. The only difference would be the altitude they would be (able) to fly at (as per 'gauge' specs). Heck, then all you would have to do is slew up to your aircrafts cieling, and let go of slew (Y key) and you are DONE (releasing the Y kew puts throttle at Max for you). Then you can go play your Nientendo games, while your plane goes cross country. When you are there you slew down to runway and press Y key to exit slew and you are DONE (the throttle will be 'automatically' be put at '0' (as per 'gauge' specs)). Shut down Sim, and PC, turn out the lights and go to bed. Or just hit the 'Master' switch at the fuse/circuit breaker box (or get a 'controler/timer' for THAT too?). I think I need to go fly the J-3 Cub now.Chuck BNapamule

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Guest FengZ
Wiwa,You want auto speed WITHOUT auto throttle? That is what is sounds like. You want to 'floor' the accelerator, and leave it there (yet it not take 'effect' until 13 seconds later if stoped), yet be able to 'automatically' (somehow) limit max speed depending entirely on altitude (and not on throttle or power setting)? What Sim do you want to use this in? And the engines are Ion Emmiters, or what? Phased Lock Loop Hydrogen Compression Rockets?You are right in thinking it would take a 'gauge' (XML) to do this. Maybe possible, maybe not (ask RCB). I don't do XML gauges. I doubt any section of Air file is capable of being made to do this 'governor' type operations (yes, plural). One would think that with pilot input when using AP and Auto Throttle and/or Auto Speed, that that would be sufficient. Unless your panel did not have a throttle lever, speed (or Mach) gauge, or altitude gauges you could read.So no matter what aircraft you were flying today, they would all exibit the same speed, and rate of climb. The only difference would be the altitude they would be (able) to fly at (as per 'gauge' specs). Heck, then all you would have to do is slew up to your aircrafts cieling, and let go of slew (Y key) and you are DONE (releasing the Y kew puts throttle at Max for you). Then you can go play your Nientendo games, while your plane goes cross country. When you are there you slew down to runway and press Y key to exit slew and you are DONE (the throttle will be 'automatically' be put at '0' (as per 'gauge' specs)). Shut down Sim, and PC, turn out the lights and go to bed. Or just hit the 'Master' switch at the fuse/circuit breaker box (or get a 'controler/timer' for THAT too?). I think I need to go fly the J-3 Cub now.Chuck BNapamule
man, relax! Where the heck did you get this info?He is clearly stating aircraft performance. Most military planes' engines are designed for high-altitude flying where the oxygen is more thin, much colder and the density low. Thus, they can reach higher speeds. Closer to sea-level, their performance is not as good (or they need to burn a lot more fuel to get into high speeds). For example, the SR-71 and the U2 are most efficient and fast at 60,000 feet and up. Their performance gets pretty bad at sea-level...relatively speaking. Here's a quick chart for the SR-71 (what we civilians knows about anyways):At 30,000 feet: Max speed: 1.10 Mach (even if the pilot put the throttle at max at this altitude, the higher temperatures at this alt will overheat the engine. It's all in the science). At 50,000 feet: Max speed: 2.10 MachAt 80,000 feet: Max speed: 3.10 MachAll he is saying that most FS military planes don't "model" this and i agree 100%. I can reach insane speeds at ground level in most FS military planes. I don't have the F-18 but sounds like they were able to pull this off.He wants a gauge that can read a plane's altitude and adjust the maximum speed/fuel burn/efficiency in real time depending on altitude and outside temperature. He is NOT talking about auto-throttles. He is talking about Science and how fuel, air density and oxygen all mix and play together. And no, real planes don't have this gauge because the real-world is made of physics and science. FS can only emulate it. Man, what's going on at Avsim lately? So much hatred...-feng

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I didnt try it, but a quick fix could be record 430 in the airfile.. raise the needed drag and lower others?Also, there is 1502 and 1506 to play with, gives thrust with throttle setting versus speed. You can even set ramdrag etc.. it pays off to study this and play with it. Trail and error works very well, time consuming yes, but no need of deep knowledge.You can make it perform as you want.Good info on the site I posted above.Johan.

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Guest napamule

Wiwa,There is not 'hate' to factual, or scientific discussion. Some whiner, with nothing to add, comes in here to criticize only. Not a valid post. Go here:http://forums1.avsim.net/index.php?showforum=122 .(Of course it's BS site. Nothing there either-as usual-ha).The air file for any/all fighter jets: F-18, T-38 Talon and Mig Firefox, for example, are all different. There is a lot you can do with changes to the aircraft.cfg that YOU can change and be effective. Each is different, so specs are different. A 'gauge' for all? I don't think it's possible. The F-18 cruises at 380 Kts. The Talon cruises at 770 Kts. The Mig-31 cruises at 1800 Kts. This tells you the cfg entries HAVE to be different. The Mach speed for each is also different. So you take each one and tweak it to suit you. Then use the same cfg and air file for 'all' (these 3, so as to 'match' performance, etc'?) Haven't tried it. I see no need.So, if you want 'custom but identical' performance from different aircraft, from sea level to FS700, then you will have to learn how to do it yourself. No one (including me) will do it for you as you are just 'playing around' with an idea, that frankly isn't 'real'. You want someone 'clever' to bring FltSimming to a new level. Then maybe YOU should do it.Chuck BNapamule

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I'm sorry if you find a fellow Flight Simulator enthusiast called a "whiner". This is a completely valid post, and not a request for others to do the work.

"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!" -wiwa
I'm enjoying the discussion about the .air file's effect with military plans and the disscussion/brainstorming at little about what might be a solution. I really know little about editing and reading the .air file to manipulate the dynamics of the planes in Flight Simulator. But I find this to be a very interesting post.Thanks for posting your question wiwa. Let's continue thinking about a solution. I for one an curious about what could be a the changes needed to the .air file to find a solution to wiwa's concern.My thoughts:...I'm thinking about it and the air resistance at sea level is a big reason for the feasibility and/or inability for a military aircraft to go around Mach2+ at low altitudes. As the atmospheric resistance decreases the aircraft is able to achieve higher speeds.In real life if, for example, a F-18 pilot run full throttle near sea level does the aircraft computers limit the top speed to preserve structural stability? or is the speed limit enforced by the atmosphere makingthe aircraft physically unable to accelerate past a certin point?If it is the computer artificially limiting the aircraft to protect the structural stability, then it might be easier to create a solution.But if it's the latter, then I fear that a lot more effort will be involved in figuring out the right settings.You really have to know about how the plane works, lol.

Derek Rogers
PC Specs: Intel i7-4790K 4.6GHz : 16GB RAM : GTX 970 4GB

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Guest napamule

Get Real! You can't 'fix' anything with discussion alone.FengZ said:'Where the heck did you get this info?' (From the 'back of my mind' where the fantasies live-like his 'gauge'). 'I don't have the F-18 but sounds like they were able to pull this off.' (It sounds like you MIGHT have looked at the SDK, the cfg and air file. Or did you see a video on YouTube of it flying, and that is how you determined this. You also don't know anything about aeronautics, air files or gauges, or how any of it works (or DON'T work) now do you.)'Man, what's going on at Avsim lately? So much hatred...' (A straight answer or reply is not 'hatred'. It's 'hard' facts. Deal with it.)This same 'sort' thinks nothing of downloading torrents and then gripe if no one helps him 'fix' things when they don't work.To just drop an 'idea' and expect results ('..someone clever enough') is not what I call 'scientific' discussion. I put his 'request' for some 'gauge' to 'fix' the Sim's mil jets doing 'overspeed' at sea level in the same category as a request that '..someone clever enough' do a Superman paint for some aircraft.The air files CAN be manipulated. But I doubt that you can 'get lucky' with the hex edits. Or balance things so that it is controlable. You can spend 3 or 4 years learning air files. But I doubt if you can EVER tweak things enough to attain what you are asking for. Take my word for it, it isn't easy to even make a few 'minor' changes, because everything interacts. If it was 'easy' then everybody would be doing 'mods'. And heaven help you if you don't back up your 'good' air file before you start making changes. To me your 'idea' is nothing more than a pipe dream. Forget it. But yak it up all you want. I'm listening.Chuck BNapamule

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Guest FengZ

Napamule,Relax, the original poster never asked anybody to "make a gauge" for him. He is simply asking if it's possible to make a tool to do this; and isn't this what a public forum is all about? Everyone else is here to help and not trash his idea. And before you start judging people and making false statements, you might want to check out their background first. Anyways, back on topic.There also could be a way to solve this via the FSUIPC module. However, like Napamule said, you can't solve this with a single gauge file for every plane. But, a guage which can read a .ini or .cfg file can work. You'll just need to tweak each file per plane. This cfg will list the max speed at certain altitudes, and this gauge will use FSUIPC to control the maximum speed. This might be the simplest and less CPU intensive way to go about it. -feng

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... 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.
To get back on topic, another point of view - maybe it's not a question of acft capability, but rather of speed limitations? So flying throttled back would actually be realistic.I'm not into jets at all, less still into supersonic, so take this just as an open question.If I look at the speed limitations of the Mirage 1 for example, following is stated:MAXIMUM SPEEDIAS 700 kt between 0 and 20,000 ftIAS 750 kt above 20,000 ftMACH limit = 2.10http://www.dooley.co.za/flight_manual.htmComparing IAS/Mach at different altitudes, actually 750 KIAS is only equal to Mach 2.1 at about 32000 ft.At sea level, 700 KIAS is equivalent to Mach 1.05, in line with what you're stating.http://www.tscm.com/mach-as.pdfI've drawn the Speed limitations into the chart, see graph.This would mean that in this example up to about 32000 ft speed is limited by IAS (drag/force on acft? - Sometimes it is stated that IAS is limited by the strength of the tail/elevators - failure due to parts braking off).Above 32000 ft speed is limited by mach force (failure due to mach buffet?).This looks to me as if flying throttled back at low altitudes, and watching IAS is realistic.And making the sim more realistic, would be to generate an overspeed failure if the appropriate speed limitations are exceeded?Actually, there is a Vmo and a Mmo entry in the aircraft.cfg, so maybe these just have to be set to the appropriate values?[Reference Speeds]max_machmax_indicated_speedNot sure whether these really have an effect on the overspeed behaviour though.Gunter

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Guest napamule

FenZ said:'..the original poster never asked anybody to "make a gauge" for him.'(Perhaps English is not your primary language?)As in- 'what do you call this?':'..Now my question? Is there any tool that can fix this?' and'I wonder if there are any clever minds that bother to make something for this?' (ie: a tool like this (ie: a 'gauge' perhaps?). READ the post. It the MEANING that counts, not the words.Gunter,Man, even a 9 yr old simmer knows that the values in 'ReferenceSpeed' section in cfg doesn't CONTROL anything. And as for your graph being 'relevant'-well, never mind (cheesh)).MS doesn't ALLOW more than M 3.199 speed (ON PAPER, or in 'print', or 'legally'). But I have Mil jets that do M 4.299 in my Sim.In the Sim all different models exhibit different flying characteristics, and capabilities (limits). Speed, control, etc. And each model can only 'use' certain specs in the cfg and air file. The FDE's for the Mirage 1 will not 'fit' the F-18. So, you will need a 'gauge' for each and every different model. The only 'one size fits all' tool that will work with all 'models' would more likely be for a VIDEO GAME F-18. But not a Flight Simulator F-18. That's all I am saying.Chuck BNapamule

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I have nothing to add for the OP, sorry.But napamule, you are a complete a#$. If you've had a bad day, or just enjoy being nasty to others, go do it somewhere else. I don't think your 'advice' is very welcome in this post or is your attitude very welcome in this forum.Have a better day.


- Red

 

 

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blah blah blahChuck BNapamule
Wow...who peed in your Wheaties these past couple days? You're blood pressure must be through the roof if something as innocent as a person asking a question on a message board upsets you this much...

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Seriously napamule, I'm not the only one with these feelings, but what is going on with your uncalled for attitude. The poster put up a question that people are willing to discuss and work together to add their two cents. If you can not add anything more than a strong negative and aggressive post, please leave this thread alone. If this continues, please move on to another forum, because your attitude is not contributing to this forum.Back to the topic at hand:

To get back on topic, another point of view - maybe it's not a question of acft capability, but rather of speed limitations? So flying throttled back would actually be realistic.I'm not into jets at all, less still into supersonic, so take this just as an open question.If I look at the speed limitations of the Mirage 1 for example, following is stated:MAXIMUM SPEEDIAS 700 kt between 0 and 20,000 ftIAS 750 kt above 20,000 ftMACH limit = 2.10http://www.dooley.co.za/flight_manual.htmComparing IAS/Mach at different altitudes, actually 750 KIAS is only equal to Mach 2.1 at about 32000 ft.At sea level, 700 KIAS is equivalent to Mach 1.05, in line with what you're stating.http://www.tscm.com/mach-as.pdfI've drawn the Speed limitations into the chart, see graph.This would mean that in this example up to about 32000 ft speed is limited by IAS (drag/force on acft? - Sometimes it is stated that IAS is limited by the strength of the tail/elevators - failure due to parts braking off).Above 32000 ft speed is limited by mach force (failure due to mach buffet?).This looks to me as if flying throttled back at low altitudes, and watching IAS is realistic.And making the sim more realistic, would be to generate an overspeed failure if the appropriate speed limitations are exceeded?Actually, there is a Vmo and a Mmo entry in the aircraft.cfg, so maybe these just have to be set to the appropriate values?[Reference Speeds]max_machmax_indicated_speedNot sure whether these really have an effect on the overspeed behaviour though.Gunter
This is a good post. Looking at the picture I can see more of the relation of speed to altitude. It almost appears that the KIAS doesn't really change but the speed does. Interesting. So I wonder if this can be achieved by imposing speed restrictions in the structure of the aircraft and taking into account the relationship to Alt and KIAS in the IAS guage of the aircraft.Therefore you could edit the .air file of the aircraft to have more realistic structural failures to the speed of the craft. And also edit the gauge to display a true IAS in mach that matches the specifications of the aircraft.To use the Mirage as an example, you would impose via the .air file (I suppose) the over-speed restrictions of the actual aircraft's structure. This is seen in many aircraft already. Next you would just edit the math behind what MACH speed is shown at the correct altitude. For example, going 700kt IAS at 10000ft would give a reading of only MACH 1.05 (My numbers are not exact.). Apon increasing to FL300 and still maintaining an IAS of 700kt you would have an increase in the MACH value, but not IAS.This reminds me of what I've seen in flying some of the commercial airliners where Mach 0.83 is equivalent to a different IAS at different altitudes.I'm not sure how the gauges operate or .air file, but this looks more feasible now. This still will be a fix applied on an aircraft-by-aircraft basis.

Derek Rogers
PC Specs: Intel i7-4790K 4.6GHz : 16GB RAM : GTX 970 4GB

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