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Guest Oruvail

Making a gauge for better flight dynamics.

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I tried to create a reasonably realistic F-15 flight-dynamics model (changing the .air and aircraft.cfg files, not the 3d model) and I've found that it's not really possible with FSX. Obviously FSX is only a relatively basic simulator but there are certain levels of accuracy which should be easily achievable. The only solution to a realistic model I can think of is to make a gauge (a .dll), but I don't know how.I am referring to the fact that in FSX the rate-of-climb for any aircraft is always far too low. I have said this somewhere else once before but found no interest. If an FSX plane is made with realistic level-speed acceleration the climb-rate is always far too low (same with Fs9). It's not that important with an airliner but with fast jets the climb-rate can be out by ~30-50% over 30000 ft, which is a lot and makes FSX not very realistic at all. There are no air file tweaks which can change this because there are no air file tables that change with pitch. This dynamic seems hard-wired in the FSX engine. The problem is that as the pitch increases the plane slows down too much. The problem with the FSX engine might be:

  • i) drag increases with pitch in FSX when it shouldn't, or ii) there is a mistaken gravitational factor coming into play, or iii) perhaps induced drag (drag from lift) should decrease with pitch and this isn't accounted for in FSX. With increased pitch, lift from the wing decreases and instead 'lift' comes from the thrust, now pushing upwards, thereby reducing induced drag [just an idea].

Any way the cause is irrelevant.I've tried changing engine spool rates and all sorts. If the thrust is made to increase with altitude then the level speed at that altitude is too high. I think I'm familiar with the air file and there's no solution. What would be needed is a gauge which either decreases drag with pitch (preferable), or increases thrust with pitch (preferably without changing the throttle). It would probably only be needed for positive pitches. 1) Is it posible to make such a gauge? 2) How would it be done, what tools, (tutorial?) etc? 3) Could someone make a simple version for me?

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Interesting. This brings to question whether the ESP runtime would suffer from the same issues. Probably not because I imagine the ESP product will benefit from continued support and updates for a longer duration than FSX given the price tag. I get the impression that product updates for FSX to fix small to medium problems (such as this one you are highlighting) ended with service pack 2 and we will now have to wait for FS 11 for these to be addressed. As far as I'm concerned, any bugs, no matter the size of impact, brought to light by users of a product should be addressed and fixed until the release of another version.

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Interesting. This brings to question whether the ESP runtime would suffer from the same issues. Probably not because I imagine the ESP product will benefit from continued support and updates for a longer duration than FSX given the price tag..... version.
I take it you've posted in the wrong thread.Correct me if I'm wrong.

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I take it you don't know what ESP is. :(
No I don't. I havn't a clue... But please tell me, I'm interested.

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Microsoft never quite say what ESP stands for (Environment Simulation Package?) but effectively it's the 'professional' version of FSX for those who either have an MSDN subscription or live in the US/Canada and want to spend huge amounts of money to buy a license. Currently the only difference between it and FSX is that ESP provides the information on creating flight models (as long as you have some idea of how to use Assembler). I suspect that even if the support for the ESP SDK is somewhat better than the FSX SDK, any relevant fixes will leak down into the FS community anyway.-Dai

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Thanks DaiI think the developers just need to take a look at it. They need to re-calibrate the engine. They should get an extreme plane like an F-15 and not an average one like a Cessna. They then need to find it's rate of climb (can climb to 30000 ft in ~60s), and it's acceleration (probably does 200 kts to Mach 1 in about 30-40s). Then they need to recreate this with all their drag variables etc set to what they want a plane like the F-15 to have in their simulator, and change their engine until they get the correct result.But before this they need to make sure the plane glides properly, to set the simulator's drag. The more extreme the plane they calibrate it with the more accurate the engine will be.darrenecm said:

This brings to question whether the ESP runtime would suffer from the same issues. Probably not because I imagine the ESP product will benefit from continued support and updates for a longer duration than FSX given the price tag. I get the impression that product updates for FSX to fix small to medium problems (such as this one you are highlighting) ended with service pack 2 and we will now have to wait for FS 11 for these to be addressed
I don't think this is a bug as such, just something that could be made alot better. It cannot be fixed with a service pack because it would change all the aircraft in FSX. Also the problem has been around atleast since FS9 and probably before, and I think FS11 is unlikely to address it.It would be nice if someone would say they too have noticed the rate-of-climb problem; I might be wrong.Also, I'd still like an answer to my original question.

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Please could someone offer me an example of a gauge that increases turbine engine thrust with aircraft pitch. I've looked through the SDK and it's too hard to learn a whole new language without some sort of starter. It's the notation which is hardest.Could someone write me a gauge string which makes thrust 30% greater at 90 degrees pitch, 10% greater at 30 degrees and so on, but not affect thrust at minus pitches?

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There's no such thing.Why would you want turbine thrust to increase with pitch? That's very unrealistic.

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ESP is supposed not to be an acronym, although reading Enterprise Simulation Platform from ESP makes a lot of sense.

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