Aircraft stability

[ahinterl 1]

During my last two real world trips in an A320 I paid much attention to the stability of the plane in the air, and I cannot help myself: in any phase of the flight - except in turbulences - even in those which I assume were performed manually (landing for instance; it was excellent VFR conditions both times), I had the impression that the plane glides through the air very stable and banks are done very smoothly.In FS2004, when I look close at what I do there with all the airliners I have, it's quite a difficult situation (I assume the plane is hand flown in the following): banking needs constant pitch correction, straight flights are almost undoable without permanent trim changes, and the landing is a fight against pitch changes and a chase for the centerline.If I image a passenger in "my plane", I doubt it would feel the same as in a real world airplane. Surely he/she could feel my efforts to keep the plane stable, and I don't quite know how my landings might feel for him/her...So, I have the overall impression that the FS airliners lack some "stability factor" which makes them more stable throughout all flight phases. I know there are parameters in the .air and .cfg files, but of course have no clue what they mean, and changing them without knowledge would probaply ruin the FDE.So, am I wrong in general, or is there a way to improve plane stability somehow?Andreas

[onurksn 1]

Andreas, I absolutely thought about the same thing sitting there as a passenger, paying attention to how the aircraft reacts on final approach and on other phases of the flight. I'm not a real world pilot but if level flight is what it's like in FS then it's a tough job!! As you've said it requires constant trim adjustments. Airbus has a notorious fly-by-wire system which of course is not yet simulated in FS, so I'm not able to compare it with an FS experience.There is one thing that I think is contrary to what you are saying though and that's how stable the aircraft is on final. Even in fair weather in real life on final Boeing, Airbus and CRJ alike are not rock solid in terms of roll as in FS. For instance look at the wingtip of the aircraft on final in any video and then observe the same thing in FS you will see the difference. In real life there are always constant corrections, it's not 100% stable, in FS this only happens when the airplane is bouncing around in turbulent weather.As to your question about improving things via the air file, I'm seeking the same answer...best regards

[ailchim 206]

I am NOT an expert or a pilot but I think you are mistaken in assuming there is much manual flying going on even in good weather conditions, apart from very short periods after take-off and before landing.Also, do remember that in the Airbus, the fly-by-wire controls are flying the aircraft at all times - so in effect, the pilot is merely giving instructions where he wants to go and the aircraft is executing the instructions via the same mechanisms that the autopilot would use. So the pilot could violently move the control stick but fly-by-wire would execute the instruction much more smoothly, subject to never exceeding the safe flight envelope.However, I know exactly what you mean! Many FS aircraft seem particularly unstable in pitch and it's especially hard to get a smooth transition between autopilot and manual flight without pitching up or down.Presumably this is largely to do with the flight model and I'm not expert enough to tell you how to modify these. I can say that the Level D B767 feels about the "heaviest" airliner I have and therefore the most realistic. I don't have the PMDG B747 which is highly rated by other people.Thereafter, you might like to think about your joystick or whatever. Many people prefer a yoke to a joystick - presumably it's then easier to make movements in one axis at a time - with a joystick, it's quite easy to make an unwanted pitch input when in fact you only want to roll.Also, look at your joystick settings and play with the null zones & sensitivity, which may tune out unwanted inputs.Lastly, have a look at your pitch controls on the FS Assignments menu. There is a repeat setting, which presumably means for every button press you get more than one input to the flight model. I think this needs to be set at the bottom of the range, otherwise there is a tendency to over-correct trim adjustments.

[pschlute 37]

Ditch the joystick and get a yoke,program it through FSUIPC and you will get much smoother control reactions from the aircraft.

[Mike_CFII_MEL 788]

Hello,I have to agree in regards to using a "good quality" Flight Yoke. I have the Jetliner Flight Yoke by Precision Flight Controls and the response from yoke movements are very smooth.The only thing missing on PFC Yokes that I would like to see as an option, would be to replace the potentiometers with optical encoders.If I had the parts and ability I would change to optical encoders myself.

[Orlaam 306]

My only real complaint in FS is the difficultly maintaining level flight while turning, or maintaining a certain pitch while turning without too many problems. FWIW, some planes in FS are much better about pitch and stability while being hand flown. I think that is one reason I gravitate so much to the Piper Cheyenne from Digital Aviation. You can really make clean turns and control all aspects of flight without moving all over the place. Some of the Dreamfleet planes are pretty good about not going pitch crazy in turns as well. I don't have the 727 of theirs so I can't say if it better that way. I don't remember how easy or difficult the PMDG 737, 747 or LDS 767 are to handle manually. I just haven't had time to fly them for months.

[ailchim 206]

Do agree with you about the Cheyenne, I'm afraid I can't fly anything else, nothing else is as good!If only there were more repaints.

[Orlaam 306]

Yeah, not many repaints, but since I spend all my time in the cockpit I don't worry too much. If only all add-on plays flew this good!

[AlaskanFlyboy 7]

I would agree with your perceptions and there are many reasons for this. In flight simulator, you lack the inertial referencing you get in real flying. You have to constantly watch gauges to keep level, while you have a good idea in a real plane just by the sensation in your vestibular system and pressure of the seat on your butt to alert you of changes.The other issue is in control systems. As some have said, many of us prefer yokes as most aircraft have them (yes, some have sticks also). Unfortunately, there are few computer joysticks or yokes with the range of movement. My CH yoke only turns about 45 degrees either direction, while the yokes in the Piper Warrior IIIs I trained in turned 90 either direction. So I'm getting two degrees worth of movement on a yoke in the real plane when I fly my Piper Warrior III for FS9 for ever one degree I get on my computer yoke. I'm not even sure the comparison for pitching, I only know my yoke has less travel on pitch as on the Warrior III's. I have fixed this through some tweaking of my joystick sensitivities within FS9 however.Also keep in mind that airline captains have a minimum of 1,500 hours of flight time under their belts (that's the requirement to get your ATP certificate in the US). Once you have 1,500 hours of flight time on flight simulator, you may be as well versed in hand-flying as they are. Think of it like seeing the work of a master carpenter and then wondering what's wrong with your tools when you go to replicate it.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satellite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004, MIDCON P-401"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

[mnmon 0]

With all due respect to many of those who produce these planes we fly, I have found about 85% of the payware, and about 95% of the freeware planes have FDE's in need of serious modification. FS can do a very good job of simulating flight, if the air file and the cfg file are set up properly. Usually this is not the case. In terms of general stability, fully 99% of all the planes out there do not have the correct moments of inertia which greatly affects how the plane reacts to control inputs. Setting the MOI's properly along with the geometry parameters can greatly aid the flight characteristics. Granted, this is a time consuming effort requiring good 3-view drawings, and doing some calculations. I find it a great addition to the hobby, but I'm sure the majority of people flying FS do not want to be bothered. However, if you want to open up a very satisfying aspect of the hobby, go search the aircraft design forum here for Ron Freimuth and Tom Goodrick. Their posts are a fantastic way to learn about FDE. Frankly, it's quite fun to get a great looking model that has a great paint job flying properly also. Mike

[AlaskanFlyboy 7]

>> With all due respect to many of those who produce these>planes we fly, I have found about 85% of the payware, and>about 95% of the freeware planes have FDE's in need of serious>modification.>> FS can do a very good job of simulating flight, if the air>file and the cfg file are set up properly. Usually this is not>the case. In terms of general stability, fully 99% of all the>planes out there do not have the correct moments of inertia>which greatly affects how the plane reacts to control inputs. >Setting the MOI's properly along with the geometry parameters>can greatly aid the flight characteristics.>> Granted, this is a time consuming effort requiring good>3-view drawings, and doing some calculations. I find it a>great addition to the hobby, but I'm sure the majority of>people flying FS do not want to be bothered. However, if you>want to open up a very satisfying aspect of the hobby, go>search the aircraft design forum here for Ron Freimuth and Tom>Goodrick. Their posts are a fantastic way to learn about>FDE.>> Frankly, it's quite fun to get a great looking model that>has a great paint job flying properly also.>> Mike>I agree to a point. The point I would contend with comes back to the issue of the end-user's control set up. Nearly all available joysticks have far less movement than a real stick, as do the yokes. This tends to cause realistic FDEs to be incredibly touchy on the controls unless you dumb down your flight control settings. I know several payware companies have a policy of trying to design the FDEs to allow the aircraft to be controllable with default joystick sensitivities.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satellite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004, MIDCON P-401"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

[rpjkw11 0]

I've downloaded a number of aircraft that pitch like a teeter-totter, even with a proper COG. What I've successfully done is adjust the [flight tuning] section in the aircraft's config. Increasing the number for the pitch_stability= item eliminate such unrealistic pitch-ups. The other items can also help where needed. I rarely leave the original as is; I always tweak.Make sure you back up the flight tuning section before making any changes, and then experiment with small increments.BobBTW: I use a joystick and no pedals as that's my preference.