MSFS flight model

[fogboundturtle 2,708]

2 minutes ago, Flic1 said:

I have noticed this much more lately since I have been mostly flying the C-310 and the C-414 (instead of airliners).  I am not sure if it is exactly what you are describing but with live WX, when you do turns the nose does not move smoothly.  It moves a few degrees, stops, and then moves a few degrees, stops...etc. I use rudder pedals but have also tested with auto rudder to eliminate an adverse yaw issue. Something is still very messed up with the flight physics at least with the lighter GA aircraft although I have noticed it with the PMDG 737 as well.  On a similar topic, with very light winds and on approach to a runway with trees on the approach, the sim is creating very unrealistic turbulence, almost making the plane incontrollable on short final.  Once over the fence this effect stops leading me to believe this is the sim trying to create turbulence from the ground objects (trees, etc). If it was a 20 kt+ wind I could understand but not light winds.  There is still a lot of work to do in this sim regarding flight models and turbulence effects IMO.  

it's not 100% asobo's fault though. Some of it is on the dev.  Floatiness of the Twotter per example is entirely on Aerosoft and has nothing to do with MSFS FM. 

[Roy Warren 434]

15 minutes ago, Bobsk8 said:

I don't get it, I have hundreds and hundreds of landings in the Fenix A 320, and have never even come close to running off the runway, or even straying far from the centerline. I have spent time adjusting the rudder parameters in MSFS, and I don't use any tiller steering, just rudder pedals. On takeoff, I concentrate on holding the centerline, and that is where I stay until rotation. 

Then maybe it has something to do with the size and weight of the airplane.  I fly GA planes, Bonanza, Cessna, Diamond. Maybe the smaller planes are just harder to steer

Roy.

[Jeeeno 314]

Ground physics is word not allowed in MSFS. Totally unrealistic behaviour, especially noticeable when there's even a small amount of crosswind.

There are some planes in which this effect is worse than the others: the CJ4 is the worst of them all, totally impossible to keep the aircraft on the centerline when there's a crosswind component of 10 knots or above. The PMDG 737 is decent, the wrong ground physics is also there, but much more manageable.

I've made tons of complaints on the MSFS forums, but there are some alleged real world pilots claiming this is the correct behaviour, so it's extremely difficult to show Asobo that they are wrong.

Asobo recently recognised that there's something wrong, but in SU10 nothing has changed despite claims. 

[lwt1971 7,456]

1 hour ago, MrBitstFlyer said:

Clearly XP12 is not going to compete with MSFS in several areas, but I am hoping the flight model is one area it may best MSFS. If so it would be good to go into XP12 for some flights where one has to really fight with the weather.

As MSFS continues to develop, hopefully the atmosphere becomes more alive.

From all what I've experienced in current sims and what I've seen in upcoming sims, MSFS continues to have the most alive/dynamic atmosphere and hopefully gets even better with the coming advancements around atmospheric airflow and weather in SU11.

Not saying you're doing this, but a lot of the talking points from the usual suspects attempt to push the narrative that MSFS is all about visuals and other sim(s) are about flight dynamics. I'm very comfortable in saying that MSFS is about *both*... visuals, flight dynamics, weather, etc 🙂 ... Asobo has already started to fix the core ground handling in SU10 and will continue after that, and that along with the advancements coming in atmospheric airflow, helis, etc is only going to make the overall aerodynamics platform that much better.

There is no single overall "flight model" in a sim but more so a flight model per aircraft.. at the end of the day much of it depends on how each particular aircraft is implemented/tweaked by the aircraft developer and how it uses and takes advantage of the core aerodynamics engine (obviously the default aircrafts are not good examples of this). Always good to go back to Matt Nischan's detailed post about flight models here: https://www.avsim.com/forums/topic/601526-msfs-has-the-most-advanced-flight-model/page/12/?tab=comments#comment-4549236 ... and when experienced developers like iniBuilds who've worked on multiple sim platforms say things like "Just to be fully clear, our flight model in MSFS is on par to XP. So those still wanting to negate MSFS as a viable sim solution based on those reasons - don’t speak too soon." then that's something noteable.

 

Edited September 2, 2022 by lwt1971

[Bobsk8 12,853]

3 minutes ago, lwt1971 said:

From all what I've experienced in current sims and what I've seen in upcoming sims, MSFS continues to have the most alive/dynamic atmosphere and hopefully gets even better with the coming advancements around atmospheric airflow and weather in SU11.

Not saying you're doing this, but a lot of the talking points from the usual suspects attempt to push the narrative that MSFS is all about visuals and other sim(s) are about flight dynamics. I'm very comfortable in saying that MSFS is about *both*, visuals, flight dynamics, weather, etc 🙂 ... Asobo has already started to fix the core ground handling in SU10 and will continue after that, and that along with the advancements coming in atmospheric airflow, helis, etc is only going to make the overall aerodynamics platform that much better.

There is no single overall "flight model" in a sim, at the end of the day much of it depends on how each particular aircraft is implemented and takes advantage of the core aerodynamics engine. Always good to go back to Matt Nischan's detailed post about how flight models here: https://www.avsim.com/forums/topic/601526-msfs-has-the-most-advanced-flight-model/page/12/?tab=comments#comment-4549236 ... and when experienced developers like iniBuilds who've worked on multiple sim platforms say things like "Just to be fully clear, our flight model in MSFS is on par to XP. So those still wanting to negate MSFS as a viable sim solution based on those reasons - don’t speak too soon." then that's something noteable.

 

I was never impressed with the FM in XP 11. I felt like a 5 year old could land an aircraft in that sim, always felt dead to me on landing. 

[sd_flyer 6,087]

22 minutes ago, tweekz said:

What did he do? Just tweak the plane correctly? So many planes in MSFS suffer from this, it feels like there's something wrong fundamentally. Maybe Milviz is working around it.

I believe Milviz is more like "they". LOL Yes I have no idea how they did but yes it's possible.

I want you to open your mind and look at a bigger picture! I have been flying for while and to me personally there are two types airframe those  that floats and ones that drop (as soon as you chop power). So  we teach in each airframe accordingly!

 Real life comes with all kind things. For example how airplane rigged will affect sensitivity of controls of exact the same type and model. Yes even among simple 172 rigging may significantly affect pilot perception especially low hours ones. In fact as, majority CFIs would have airplanes on their list they prefer to teach in over others. Some airplanes even have nicknames based on they characteristics.

This just one aspect of many which may include worn out engine with low cylinder compression, modified  long range fuel tanks that will affect performance and reduce useful load. Or even simple fixed pitch propeller that  tweaked for cruise , climb or both. No to mention effect of variable pitch prop three bladed vs two bladed. I'm not aware of any sim that  model all of that. Perhaps some developer can model particular airframe, but them again simmer will look at POH and will complain that numbers are off LOL

So  I approach all sims as approach real life airplane. I adjust to whatever is offerred given realism is reasonable enough for me to accept!

Why, for example, pilot float in real life? Because excess speed! Right? So you probably need to lower your approach speed. Some people say it's not realistic! I say yes it is.

Believe it or not I just flew 172N that got modified with 180hp mod (IRL of course). I have no idea where engine was modified  Penn Yan Aero or somewere else. I had instructional flight first time after this airframe went back on line. Guess what it ? It flew nothing like no other 172 no even familiar to me S model that already comes with 180 by factory default!

We got airborne, but none of familiar to me power setting seem worked. So now what? We took her out and did some airwork stalls, slow flight, steep turns. I made rough sketch of power settings. When time came to head home, we couldn't descent at 85kts using 1700-1400 rpm. We keep getting 100-95 kts (Note Vfe for N model is 85 kts.) Gotta slow down right? My student got frustrated so I took over. We should we do? I can't call owner and ask him to patch it because it doesn't behave realistic! LOL Right? So I set power to idle, pitch up, and bled  airspeed to 85kts. We practically glided on idle until we dropped first 10 degrees of flaps than 20..After that things went butter. We added power get to 65kts over the fence cut power and glided like regular 172 to touch down. Happy ending except my student don't want to flight that particular 172 anymore LOL

So my approach to take any sim with grain of slot. Adjust to wat it get offer. Hope for the best. MSFS even in this state has a lot of to offer. It constantly evolving in changing. Nothing is perfect in this world after all. However, while MSFS has potential of improving flight physics to compete with X-plane 12. I believe X-plane 12 will unlikely in foreseeable future can compete with MSFS in visual department.

[lwt1971 7,456]

4 minutes ago, Jeeeno said:

Asobo recently recognised that there's something wrong, but in SU10 nothing has changed despite claims. 

Not quite, see below.. Aircrafts will have to start using these new parameters and capabilities introduced in SU10, and hopefully updates for our favorite 3rd party birds will come soon after SU10. I'm not in the beta, but per what Seb says below, the default aircraft Extra 330 might've been updated to use these?
 

From a recent Q&A: https://forums.flightsimulator.com/t/live-dev-q-a-may-25th-2022/521293/2
Chat question – What are some improvements that are coming for ground friction and handling? - Timestamp 3

Seb – Four new parameters are coming in Sim Update 10. Two of them are going to give the possibility to eliminate or at least tune, but we decided to cancel it out on our plane where we tested it. Basically, an old feature that we kept from FSX. FSX was canceling out all crosswind below a certain speed. At 50 knots, you had 100% crosswind, and then it was fading out to 10 knots and then it was 0. The problem is, while you take off or land, the crosswind keeps changing. And it’s very unnatural. So this is something where, in the parameters for the plane you can say at what speeds you want this to happen. So on the Cessna 172, we’re testing this, so we basically canceled the effect completely. So you have a 100% crosswind even if you are parked, or if you go very slow. If there is a lot of wind, it can actually spin your plane around, at first. So that’s one of the new parameters.

Seb – And the other one, two parameters are there to allow you to control how sticky your wheels are when they are rolling fast. So when you are already going pretty fast in the takeoff, the sim was considering the wheels to be pretty much on rails as if there were slick tires from a Formula 1 car. Very sticky. And only the weight…so if you pull on the yoke, your plane gets a bit lighter. And the weight goes down, which reduces friction a little bit. But it’s still static. So it means that as long as you don’t push to the side strong enough, you’re still on rails. And so, there’s two parameters that allow you to make it so that the plane drifts off. The wheels are spinning so if you push to the side, it’s going to drift off a little bit, especially with plane tires that are not anything but racing tires. So we tested that with taildraggers. Taildraggers will always be hard to land and takeoff. But it’s a lot more natural and easy with that. So this is something we implemented on the Extra 330 for Sim Update 10. Also, plane makers have examples of how this works, so they can use it, too. We will deploy on more based on feedback. These four parameters are a first step on improving the ground handling. So more stuff will come afterwards. But Sim Update 10 is going to be these four.

[Rocky 128]

I made some additional tests with the C172 (propeller for torque effect) and CJ4 (no torque effect), only standard planes, no 3rd party.
What I did is customize the weather to remove ALL winds, no wind at all, no crosswind.

With the C172, I had to apply some right rudder on take off because of the torque effect, this is OK, and I could land perfectly without experiencing any drift when landing, not in the air and not on ground.
Same with the CJ4, and even better because it has no propeller: when taking off the plane remained on the runway center line, and again I could land without any problem and kept the aircraft on the runway center during rollout.

My conclusion: this test confirms the whole problem comes from the way the crosswind is managed in the sim, with a possible relation with the ground physics. But I must say I couldn't notice any ground physics issue when wind was cancelled.

I hope Asobo will fix this soon because at it was said, take off and landing are the actions you always do, whatever flight you do.

 

[Snuffleupagus 328]

I’ve noticed this also. Another thing I’ve been somewhat disappointed in is the overall flight model/physics. Planes react in a ‘twitchy’ kind of way when airborne. 

[Jeeeno 314]

16 minutes ago, lwt1971 said:

Not quite, see below.. Aircrafts will have to start using these new parameters and capabilities introduced in SU10, and hopefully updates for our favorite 3rd party birds will come soon after SU10. I'm not in the beta, but per what Seb says below, the default aircraft Extra 330 might've been updated to use these?
 

 

According to people who downloaded the SU10 Beta on the forum, there just two parameters, not 4 in the current build and I'm not expecting that to change.

Furthermore, their solution to the problem is basically deleting the effect instead of correctly simulate it. Quite appaling. 

[sd_flyer 6,087]

8 minutes ago, Hatch76 said:

I’ve noticed this also. Another thing I’ve been somewhat disappointed in is the overall flight model/physics. Planes react in a ‘twitchy’ kind of way when airborne. 

One of the "holy duties" of each simmer is to tweak sensitivity control to their liking/believe! LOL Without it there will be a lot of problems.  I did tweaked my TM Airbus stick and Logitech rudders. Power, pitch, trim and my airplanes never twitch! 🙂

[fogboundturtle 2,708]

Just now, Jeeeno said:

 

According to people who downloaded the SU10 Beta on the forum, there just two parameters, not 4 in the current build and I'm not expecting that to change.

Furthermore, their solution to the problem is basically deleting the effect instead of correctly simulate it. Quite appaling. 

Did you even listen to the Q&A or you are just rambling nonsense ? They said the issue was ground handling was FSX legacy code and they were just patching it for now as it needs to be re-written from scratch. they will do that at a later date. they think this will help for now. But they are aware of this issue. 

[Bobsk8 12,853]

2 minutes ago, sd_flyer said:

One of the "holy duties" of each simmer is to tweak sensitivity control to their liking/believe! LOL Without it there will be a lot of problems.  I did tweaked my TM Airbus stick and Logitech rudders. Power, pitch, trim and my airplanes never twitch! 🙂

I can remember during the days of FSK, going over to a friends house that was complaining  that the sim was "unrealistic", and trying to fly their sim with their control setup, finding it impossible to control. After I spent about 10 minutes tweaking their controls, I told  them to "try it now" and they were amazed at the difference. I have around 10 payware aircraft for MSFS, and find none of them to be "twitchy." 

I can remember on my first cross country dual when getting ready for my PPL, the instructor asking me to look up something on the sectional. While I did this, he would take over the controls. When he did this, all of a sudden, the turbulence I had been experiencing when I was flying, seemed to disappear. When he handed the controls back to me, the turbulence returned. I finally said to him. "how come when you take over the controls, the turbulence disappears?".  He said, " You are making your own turbulence, a wing drops a bit and you try and "yank it back up"  Just relax and let the aircraft fly over the bumps, it will come back to level on it's own. "  Once I realized that, all my flights were much smoother. 

[Flic1 999]

38 minutes ago, Jeeeno said:

There are some planes in which this effect is worse than the others: the CJ4 is the worst of them all, totally impossible to keep the aircraft on the centerline when there's a crosswind component of 10 knots or above. The PMDG 737 is decent, the wrong ground physics is also there, but much more manageable.

I've made tons of complaints on the MSFS forums, but there are some alleged real world pilots claiming this is the correct behaviour, so it's extremely difficult to show Asobo that they are wrong.

It is not proper behavior (RW pilot here).  What I do in some of these aircraft is turn on 'Auto Rudder', especially in the CJ4. It will give you more stability on takeoffs/landings. Although not "realistic".... it is better than being thrown around like a balsa wood airplane with a 6kt crosswind.

[enright 496]

3 hours ago, sd_flyer said:

This is actually correct behavior with cross winds. Nose point into the wind and airplane drift . Take a look

Sorry, I wasn't very clear - I'm not referring to the need to crab into the wind, and I agree that is totally normal and accurate. I'm referring to the rapid uncommanded variations in yaw - usually in live weather with windy or gusty conditions - as if a rubber band were attached to the nose of the airplane and pulling it side to side. It's more noticeable in smaller planes, but the effect is exaggerated in all aircraft.