Flight Dynamics - Realisim ?

[Guest Funky D]

>As you make small changes in pitch and roll on short final the >resulting movement just isn't fluidAll FS aircraft seem to be too sensitive during slow flight. At high angles of attack the ailerons should have little effectivness... you really need to "snap" the stick to get the plane to roll the way you want. Directional control at a high angles of attack is made with mostly the rudder. FS aircraft seem even MORE sensitive to roll when landing, especially during the flare. Then again, maybe this is just a result of not "feeling" the roll of the AC and being able to counter-act it soon enough.Paul

[lcseale53 0]

Amen Rudi,A little too much theory in the masses I think. I own and fly a Cessna 120 and a Cessna 206 (which pretty much covers the span of single engine GA aircraft - at least in terms of gross weight). And you are correct...there is no perception of rolling inertia in either airplane. Guys - consider also precision aerobatics performed by much heavier aircraft, where inertial 'overshoot' would be catastrophic. Microsoft has done a remarkable job in modeling flight, creating great visuals (which are better than multi-million dollar full-motion simulators), and leaving an open platform for third-party developers - all for the paltry sum of 50 bucks...remarkable.Leon

[michal 44]

>A little too much theory in the masses I think. I think too. Regardless if one calls it inertia or roll dumping or whatever my C172 behaves completely differently than its FS9's counterpart. Significantly different in roll but difference in pitch behavior is just mind boggling. Regardless how light my C172 is it does not bounce around as quikly and jerky as some demented yoyo. I am glad that we have talented air file specialists like Ron Freimuth (post above), Robert Young or Steve Small - all experienced aviators who recognized shortcomings in the MSFS implementation and could fix it. Yes, thanks to MS for giving us great world scenery, weather with airport database for mere $50. It's a steal.Michael J.http://www.reality-xp.com/community/nr/rsc/rxp-higher.jpg

[lcseale53 0]

Absolutely Michael,Many thanks to the talent given so abundantly by these folks. It's the reason we so greatly anticipate our daily stroll through the file libraries - sort of like leafing through the old Sears Christmas catalog as kids (you probably have to be in your 40's or so to remember that).Leon

[Guest Digital_Flight]

Ok, I see what you're saying now. It's a given that it's always a matter of balance between tail forces, CG moment, center of lift, total lift and weight. I just wanted to make clear that the aft postion of the yoke is a function of low speed, not because of any change in the CG moment.TonyDigital-Flight

[Guest Ron Freimuth]

>>>A little too much theory in the masses I think. >>I think too. Regardless if one calls it inertia or roll>dumping or whatever my C172 behaves completely differently>than its FS9's counterpart. Significantly different in roll>but difference in pitch behavior is just mind boggling.>Regardless how light my C172 is it does not bounce around as>quikly and jerky as some demented yoyo. I am glad that we have>talented air file specialists like Ron Freimuth (post above),>Robert Young or Steve Small - all experienced aviators who>recognized shortcomings in the MSFS implementation and could>fix it. Yes, thanks to MS for giving us great world scenery,>weather with airport database for mere $50. It's a steal.>Michael J. Several years ago I worked with a guy no longer posting here to develop a more realistic C172. He flew one in a club and also had othe's familier with the AC critique it. This was before we understood the details of the AIR file and flight modeling very well. So, we set Roll Damping, etc. by effects. Seems the values turned out to be pretty close to published values that could be used when the AIR file became better understood. I got a new PC recently and installed FS2K4 on it. It was hard to copy my custom AC to the new system so I flew FS9 with the default AC a bit. My initial impression was that the AC were way too stiff. They would roll into and out of a bank with no 'inertial delay'. The fact I had moved from a 467 MHz to a 2.6 GHz system was secondary. All that did was let me set a lot of clouds and get better frame rates when on a runway. I've flown same basic simulator since it was on a C-64. It wasn't until a few years ago that there was much of any way to get into the FD's and think about adjustments. And, it was only after I had to start thinking about more realistic FD's that I had much of any complaints about the defaults. ;) Even the old C-64 flight simulator was remarkable at times in how well it simulated flight. Especially with the plug in sound module and a color monitor. At night I could see lots of airport beacons and other lights. Nowadays any half decent flight simulator gives one a general impression of flight. It's only when he gets more critical and has some experience with real AC or, perhaps other simulators, that he may begin to see the faults. While I concentrate on details of light dynamics, one of the main problems I have flying any MSFS AC is that I can't move my head to glance out the window to see where the runway is. Or, just move my eyes to see an important gauge. When I am on final, I can't see the runway as I could in a real aircraft. There just isn't room for much of a panel and a realistic View. Can't blame MS for that, in fact multiple monitors can help a bit. Ron

[Guest Digital_Flight]

I really can't believe that the way many MSFS aircraft are responding matches what you see when you go flying in the real world. It certainly doesn't match my experience in sailplanes and I don't remember seeing it when I've been right seat in a 172. What I'm talking about here is most noticeable just before and during the landing flair and can be seen in both large and small aircraft. That is the tendency of the aircraft to move from point to point in pitch and roll in a way that just seems very unnatural. There seems to be no ramping up of the motion at the start of the attitude change or ramping down when it's neutralized. It's as if the rate of attitude change goes from zero to a given rate and back to zero again within a single simulation frame. If you plotted the motion it would look like a square wave with no rounding of the corners. I'm not talking about a huge inertial effect with the rates overshooting all over the place but rather just the natural way in which any object is expected to react when subjected to a force. A 172 might not have a huge roll or pitch moment but it's not zero and the effect is not limited to small aircraft. I see the same thing in the stock 737. I use the proper FOV for my viewing distance and screen size and my frame rates are locked at 30. However, in the tests I've done frame rate do not seem to be a factor.TonyDigital-Flight

[Guest Digital_Flight]

IMO another factor in this is the widespread use of incorrect FOVs. With so many people flying in the 3D cockpit and with such great scenery to look at the tendency seems to be to zoom out so you get a great looking, impressive view. The only problem with that is, it ruins your perception of rates and can really screw up your perception of where things actually are when you switch to other viewing angles. Flying at the default 1.0x zoom setting is going to be pretty close to correct for typical monitor sizes and viewing distances if you're treating the monitor as a realistic window to a simulated outside world. I've found that for doing things like flying the pattern and landing it makes a big difference in my ability to judge angles, rates and speeds. With so many high quality custom aircraft resetting the viewing angle to 0.75 or wider by default, this is something to think about.TonyDigital-Flight

[Guest A_Delta_Sierra]

Let me relate my experience with my grade/high school best friend who went and became an F4 driver while I pushed dirt. We recently got back together after 40 years and he came over last night and after a few glasses of wine I showed him the Tweet that I recently purchased. Ron Freimuth did the FD for it.The Maj (retired airforce)friend after his tour in Vietnam came back and was a IP in the Tweet for two years. After that he served at the Pentagon and one task was looking at training simulators. From this background I was kinda of scared to even show him the FS9 with the Tweet. He is the closest thing to an expert that I have seen. Having many hours AND simulator knowledge. Well I got brave and showed him the article on page 29 in the Jan issue of "FLYING" (real world aircraft monthly read by real world flyers and a few FS9 owners) which featured of all things the Tweet simulator for FS9. I had purcahsed it 2 weeks ago just to have the Maj tell me what he thought.Now keep in mind, the Major has never pretended with Microsoft simulator software before. I saved a flight starting at 4K and 200 knts all trimed and stable. I paused it, showed him the detailed defalut scenery of the area where we live in Central Illinois, reviewed the gauges in the tweet which are where they belong and appear correctly per my expert. I then attempted to fly the tweet and talk to him. Didn't work out that good. (I don't fly r/w.) I then explanined the location of the trim, flaps and gear buttons on my Saitek X45 to him and let him try it. Humble time is here.Would you believe that without ANY MS FS experience he was able to take off from our local pekin airport C15, get the gear, flaps, and manage the power right to 6000 feet and 200 knots and level just like he said he would prior to takeoff? He then did an aileron roll. Not perfect, but it was his first one. I then tuned in the PIA vor and turned and fly right over the top of it. He was SMOOTH and did it all by just looking straight ahead, managing power and climb rate and the attitude indicator. No need to look out side for him. Smooth smooth smooth is the name of his "game".My conclusion right then was:The tweet addon for FS9 must be real close to right on the money becasue the Maj had ZERO MS flight simulator experience but tons of Tweet experience. Great Job RonF on the flight dynamics/power/drag/roll rates. The only slight negative observation was adverse yaw when rolling the aircraft was not as pronounce as in the real Tweet. He said that the airforce would have paid millions for such a quality program had it been available in the 80s when he was in the Pentagon.You mileage may differ, but this is one happy camper with FS9 and the Tweet. Shucks, I may even have a real world experienced Tweet instructor to teach me how to fly the overhead approach and do the various aerobatics of a combat pilot. And I won't even have to barf in a bag. ;-)Regards,BobS

[Geofa 108]

I agree completely-and it puzzles me that MS is always called an "eye candy" sim-and the fm's dismissed as complete rubish .When it comes down to it-even with add on mesh, textures, and autogen-the fs view out the window doesn't really look much like reality (it does a pretty good simulation though)The weather-even with real weather downloads (when they work) still doesn't match the infinite variety of sky conditions and clouds (it simulates them pretty well though)The cockpits still are lacking much realistic instrumentation and instrument response is still lacking (though pretty good for simulation)The outside renditions of the aircraft are fairly realistic (though they look too pretty, new, and clean-but pretty fantastic for simulation).Atc isn't perfect-and it certainly doesn't get my aircraft type or call sign wrong like real world atc does much of the time :-)As far as the fm's-without motion to go along, and without the 3d immersion you mention-they will always not be "right".The list goes on and on-but I don't really find the fm's any more substandard than any other aspect of the "sim".The scenery isn't perfect either-that's why we have mesh and scenery add ons. The atc isn't perfect-that is why RC. The instruments need improvement-Reality -xp. The flight models-yes-Ron ,Steve, Rob etc. MSFS isn't quite a "reality" double yet in any aspect-but it sure simulates quite a bit extremely well-a lot better than other programs costing much more, or cardboard inserts the airforce might use (I reference an article in Flying this month that mentions the airforce using ms instead of cardboard inserts to suppliment enhance flight training).The mind can fill in all of these present holes very well-and at least mine does quite fine at this. Future improvements can be imagined and requested, and probably will happen. No matter what the improvements though-there will always be that difference between the "sim" and reality-Thank God-and we will always find these weaknesses and continue upward-Thank God-in making a better sim!http://mywebpages.comcast.net/geofa/pages/Geofdog2.jpg

[Guest Digital_Flight]

That's great Bob. I whish all the X Plane users who think MSFS is just a toy could read your post.I don't mean to give the wrong impression here. I think that when running the best flight models MSFS does a great job overall. It's just that one little area as described in my last post that really bothers me.TonyDigital-Flight