Unrealistic low speed aerodynamics on / near ground

As a real world pilot, I feel that low speed aerodynamics, especially on the ground with high thrust, are wrong.

  1. A C152/C172 does not lift its nose with basically zero airspeed
  2. The TBM 930 lifts its nose at ca. 40kts with full elevator. Having flown the PC-12, which is a comparable aircraft, I can tell you that this is simply not the case.
  3. I guess this behavior is mostly wrong for all aircraft models, as even the airliners lift their noses at ca. 80kts!
  4. Aircraft lift off the ground under the stall speed. In real life, they do not do that. It is part of the idea of drawing the airspeed arcs on the speedometers. Ground effect does not have a large effect on speed, but more so on drag.
  5. Right after lift-off and out of ground effect, aircraft struggle to accelerate (even at low density altitudes) which is simply wrong, especially for powerful aircraft such as the TBM 930.
  6. In landing flares, stall at low airspeeds is too soft / delayed. In real life, there is a point at which the wing stalls.

It would be great to get some more realistic aerodynamics.

Bonus point: Nose wheel steering is also not aggressive enough. In real life, the nose wheel is much more responsive, even in Cessnas, and has much more grip. Usually, it is not necessary to apply brakes to steer.

PS: I consider FS to currently be in ā€œpublic betaā€ (thatā€™s the best I can describe it). As this, it it our responsibility to report bugs and short-comings of the program. This is in our own best interest and in the interest of the community. Only issues that get reported have a chance to get fixed / improved.

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I disagree. For me the nose-wheel steering feels spot-on. Including the need for differential breaking. When Iā€™ve flown the 172 IRL and start the sim directly after, it feels almost the same.

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I agree that there are some low speed aerodynamic issues. The C152/C172 in real life are definitely not as forgiving at very low speed as they currently are in the sim. Having said that, overall very impressed with the simulation of stall etc and possibility for spinning are much improved over previous sims. Only a small amount of work to get it spot on.

There are also potential issues with the cockpit airspeed indications in some of these situations. For example aircraft such as the C152/C172 in real life may have significant variation in the calibrated vs indicated airspeed at low speeds/high angles of attack, potentially up to 10 knot difference etc. (I suspect that the sim does not currently make any correction for that and that if allowance was made for that, it would actually make the simulation appear worse!)

The one thing that people need to be cautious about though, is that it is possible for pilots in the sim to completely mishandle the aircraft. Many situations in real life may have only been explored in test flight programs or possibly not at all.

For example, applying and holding full up elevator at lowish speeds early on the takeoff roll in an airliner is absolutely not normal procedure. However in the sim, essentially any and all inputs (appropriate or otherwise) are possible. Some things the sim may do may seem unrealistic at first glance, simply because it would never be done deliberately in the real world. Possibly in some of these situations, the sim may not be too far offā€¦

I know that the C172 nose wheel is slaved, but not by that much. Pay attention to turn radii without power.

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In light aircraft (and even in some SET), itā€™s completely normal for soft-field take-offs to apply full back elevator during the begin of the take-off roll to reduce load on the front wheel asap. I agree that airliners are operated differently and this would never apply in real life. I tested it just to see if this is consistently ā€œwrongā€ :slight_smile:

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Big fan of the other small Sim, it was positively surprised about the reactivity or the Cessna, being myself PPL.
I appreciate that:

  1. The aircraft often needs some small corrections (pitch or bank), and in real life, even trimmed, an aircraft does not stay steady a very long time.

  2. The overall behaviour when landing

What could be improved:

  1. Ground starting: usually 1500 rpm.briefly.(then back to.1000), this enough engine power to start to roll up. Here I need 2000 rpm to start rolling, and there are too much inertia for the movement to start.

  2. The IAS seems to decrease too rapidly compared with real life when decreasing or shutting down the throttles. (In my opinion, in XP11, thatā€™s more realistic)

  3. Ground rotations (backtrack). Take.a.too big diameter to achieve those types of movements wirh high rpm, for brakes and rudder

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Hello all,

I think this will be different from user to user. Reason? No one from us has proper yoke with some strength feelings as real Cessna has, maybe my yoke is made myself from iron and has some very real feeling. I must not agree with close time to touch ground with not at some point stall comming, with phase of holding time. It feels to me very accurate and try with my yoke with itā€™s weight make some corrections to be stay sometimes still in air. In case of holding it at straight alt/direction, tried hold that altitude before stall, at some time it can hold altitude fine and then after some time stall own, need also correction do but i feel very good C172. I had C182 at my hands so can compare, my luck but again, all is with set your controls iniside sim and I spent about 1 day to be satisfied +/- due my yoke of course. That means other controls can feel different.

Update: sry but I just feel to say that talking about not correct dynamics is here very speculated, due my mentioned things, I hope you all understand now that this can be simply different from one user to other. This can be never solved and if we say that in other sim was all very good and close to reality, I donā€™t agree. I must set everytime control sensitivities very hard and also dead zones, therefore I feel this MS system very good about sensitivity and dead zones cfg.

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All with complaints of low level speed ā€˜lightnessā€™ from the aircraft, are you adding proper weight in the setup? Iā€™ve seen a lot of streamers ā€˜mentionā€™ about float but also see that they fly the aircraft very empty of fuel and passengers and luggage (on the larger jets).

Try loading all 4ā€¦6ā€¦10ā€¦200 seats with passengers and luggage and have enough extra fuel at landing as you should and then see how floaty they are? If itā€™s still an issue then ok you are probably on to something and should raise it but at least give it a try :slight_smile:

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@DaintierOcean3 I could,'t have said better, that is exactly what I discover, I can even lift the noise of the C152 at 35kts under the VSO???

An engine weather that is totally broken + wrong aerodynomics = NO REALSIM
So easy to do the empirical maths as a matter of fact.

I asked myself where is the simulation here therefore where is the realism annonced? Where is the flight simulator if such important basic features that make the realism are absent?
I donā€™t see a sim but a beautiful game which wasnā€™t planned when I opened my wallet at the released dateā€¦ Now hopefully I will see a flight simulator as planned when I did bought MFS2020 if an update lands quickly on our wayā€¦ by waiting I lead myself back to Xplane to avoid such frustrationā€¦

Thank you for your precise statement

Cheers

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I donā€™t know what you want. I tell you that from my own experience the sim (or at least the rudder) feels very realistic and you donā€™t agree? :smiley: Let that sink in for a bitā€¦

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I have indeed not. I can tell you however that the small Cessnas donā€™t even behave like this when they are empty. But I shall try loading them up, thanks for the input.

I undertstand that modelling aerodynamics is complex and it will take tweaking to get it right. I understand we are in ā€œpublic betaā€ right now, and it is our job to let the devs know what needs improvement, so we will get a great sim soon.

Hi,

do you better return so to XP as also with CTDs and TBM900? :wink:

Actually the flight models of GA aircrafts I know of seems to be 5 to 10% off of reality. I flew the C150/152/172, PA28, BE36, BE55 and B737, I can only speak of my current experience and feeling.

The C152 for instance is a little bit sluggish on take off, struggling to accelerate to Vy speed with flaps 10, again just by 10%. Same when I reduce RPMs to 2200 with carb heat. It doesnā€™t slow down in the white arc as I remember, just missing a few more knots. And while Flaps 20 looks like quite correct regarding lift/drag, as soon as you bring full flaps, it falls like a brick even with a decent amount of power. I found the aircraft to be extremely difficult to get out from the back of the power curve and lending itself to easily stay stuck in it.

As of the BE36, All the Pitch/Power settings Iā€™ve been applying back in the days of my IFR training are quite close, just off by 5/10%, againā€¦ Except with Full flaps on final, 14ā€™ MP / 2300 RPM should give something close to 90kts with a ~600/800 fpm descent. Instead, it goes down heavily, struggling to maintain speed ^^. Same behavior, once itā€™s down at 75kts on short final, you need a hell of a lot of power to keep a 500fpm descent.

I think the flight model just need a few tweaks here and there, especially with the drag curves at different configurations. Itā€™s just my few cents, I do agree with the initial post and while everything is down to personal taste and memory of past experience IRL, I still think the FM doesnā€™t need much to be spot on (For GA aircrafts at leastā€¦ Anything past the TBM is another storyā€¦)

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I suspect what I was describing might have to do with the ground effect model. Maybe that needs some tweaking too.

My take on it is just the opposite. I have always felt that nosewheel steering via rudder pedals in sims like FSX and P3D is far too easy and too responsive, especially when making sharp turns at low taxi speeds.

In a real 172, you have to step hard on the pedal and push it almost all the way to the floor to execute a ninety degree turn, and the pedal does offer some physical resistance. It is much easier to add a bit of differential braking in the real aircraft to help it around a sharp turn.

Large aircraft (airliners) use hydraulic-powered nose wheel steering controlled by a tiller, and I donā€™t think MSFS currently emulates that, so even the 747 has to be steered by rudder pedals at the moment, which is not particularly realistic.

Buddy no matter what payload you set, the flight model/aerodynamism and the interaction of the airplane with the elements of outside as the Alti-pressure/temperature are totally wrong, it doesnā€™t interact at all with your bird which is the minimum required if we dare talking about realism even a modest one!

Concerning the VR Speed in general i canā€™t understand why it was released this way, really I canā€™t figure it out, itā€™s so so buggy that it is a mysterious especially when I watch back the advertisings through Youtube videos, it feels like a ā€œbad jokeā€! Not even need to be a real pilot to notice that you canā€™t make a rotation at 35kts with a C152 at 38Ā°c at DAAT with 6kt of wind in your back (just for testing) ! How come?! itā€™s definitely unrealistic, we canā€™t be blind here, itā€™s in front of our eyes if we do care about the airspeed information (we should hhh) ā€¦ same for the wrong behavior of the TBM, you canā€™t even use 25% of the POH, just impossible, numbers donā€™t match at all with the base of realism requiredā€¦ The DR400 feels like ā€œrealisticā€ somehow in terms of flight model and the Cub as well (I wonā€™t talk about tubes which are unfinished products, you can even set the correct values in the FMC just to pratice your IFR procedures, how come for a Simulator? Please how is it possible in a first released, itā€™s like I buy a brand new car and the seller tells me everything is ok but you have to wait to have the brakes?)ā€¦ We are not talking about small bugs here but about huge basic major issues!

Anyway the alterity between the birds and outside do not match in a realistic wayā€¦ The DR400 has some good points in terms of flight model but still we just canā€™t talk about realism here as the DR400 is a way under power as it should be, however the behavior gives to some GA birds some kind of good illusion thatā€™s right but again thereā€™s no realism in terms of pure aviationā€¦The DR400 itā€™s one of the birds that I flew for a while when I was a student pilot, it doesnā€™t make me an expert in front of everybody of course but I do know what I meanā€¦

Anyway, even a single pilot with 50lbs of bagage on board at 75% of fuel wonā€™t never rotate at 35kts or fly a TBM like we do in MFS2020, just because of the laws of physics of Mother Nature that MFS2020 was supposed to reproduce as much as it is technically possible but they didnā€™t! They said they did but they didnā€™t, why? I have no idea and itā€™s a good subject for polemics we can avoid thatā€¦

Anyway even a stock bird of Xplane canā€™t allow to let you taking off your plane with such ā€œcrazyā€ VR speed values! ā€¦ Trust me, the aerodynamics are very wrong, itā€™s far from realism matter, very far like it is in an arcade-game as a matter of fact. I donā€™t really care about my opinion, itā€™s factual here, itā€™s wrong, itā€™s totally far away from what Microsoft claimed in terms of realismā€¦ I didnā€™t expect that of course based on such advertisings very promising (maybe too much) I mean it :wink:

After once the DR400 or the C152 or the Cub are in the air even if you can fly through TS/CB without any effect or damage (???) how weird does it sound if we talk about realism??? You should avoid CB if you fly a Cub for the sake of safety (or for the sake of realism in a sim)ā€¦ Well letā€™s say that both of the birds behave in a certain coherent way, itā€™s just a good and comfrotable illusion so that I do understand that people have good feelings, same here but if we talk about realism itā€™s another story trust me on that if possibleā€¦ and again there is no interaction with outside-elements as it should be, you should manage your engine at different FL during climbing after 3000 ft (in general) especially if you fly piston-aircraft, you have to deal with your mixture by leaning it based on Alti-pressure as published in the Book and check your EGT, CHT that should be drastically affected if you do nothing (which is the base of flying piston) etc also the OAT is a factor that will affect your perfs for T/O and Climb phase etcā€¦ those are some elements that will directly affect your engine and your imputs to manage the heart of your bird etcā€¦ Those are elements that Xplane cares in a very realistic way, they did work years on flight dynamism/physics and it does the job, its factual not opinion but sure there is no rainbow, no elephants which should come because I really enjoyed flying around the fauna, I even disturbed an elephant family (sorry for that) but it was very immersive in this way to land the Cub between trees in Africa, so well done as never seen, good job MFS2020 for that!

To conclude, based on the test I made modestly with MFS2020 and the Book on my knee, itā€™s impossible to fly by numbers in anyways like we can easily do on Xplane for instanceā€¦

Sure we have beauty panorama outside and gorgeous visual aspects as never seen in a sim before no doubt but is it a Flight Simulator because of eye-candy stuff that provide such a pleasure for our eyes and our senses if the essential base of realism is absent?

Without any sort sterile polemic here of course itā€™s easy to say for now that it is a great game but not a Flight Simulator as it was announced so loudly, I believed in it, I even talked to real pilotsā€™ friends on Xplane and simmers to say ā€œgo for itā€ ! ā€¦ all of them except one (Iā€™m sorry for him because we now share the same feelings about MFS2020 even without talking about it previously, I owe him a bunch of beers or a good bottle of French wine) ā€¦ all of them said to me you should wait before buying this sim in order to calm my enthousiasm down but no regret I did enjoy some beautiful things in MFS2020 and itā€™s not the end of MFS2020 (updates, patches) but for the starting it really makes me worried by the fact that the minimum realism required is definitely not there which was replaced by a genius illusion, nice for the senses and because of beauty that this game brings in our virtual skies and all other visual aspectsā€¦ but I definitely go back to Xplane waiting for MFS2020 updates if it becomes a simulator, even if Xplane is not the real life of course we canā€™t get to there but itā€™s the most realistic sim on the market so farā€¦ at least there are some reliable stuff that lead to some realism as a matter of fact. Sure I will miss my rainbow, my elephants, the amazing lights and the beautiful panoramaā€¦ Now Xplane feels empty after my first flight on it this morning that is true since the August 18th but I aldready miss some realism by flying MFS2020ā€¦ Iā€™m not bashing the game of course, Iā€™m talking about empirical facts. Iā€™ll wait with patience if it becomes a Flight Simulator or not!

Whish you Happy Landings anyways, thereā€™s always a place to enjoy no matter the sim we use ! :wink:

Cheers

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In real life, light Cessna nose wheel steering is spring loaded and not directly linked. Which means there is some delay for the wheel to respond. But not as slow as in the FS and it is certainly possible to perform tighter turns without using brake pedals. As a matter of fact, we always taught out students to avoid using brake pedals for steering, even though it is easier and the ā€œlazyā€ method, but obviously uses up brakes and tires.

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Thnx for opinionā€¦

Youā€™re welcome Captain! :wink:

Regarding aerodynamics and aircraft handling, MSFS2020 is unrealistic and certainly NOT safe to be used for actual flight training, especially for takeoff and landing. Itā€™s a fantastic procedural trainer with superb graphics, but thatā€™s it. Aerodynamics are a notoriously difficult thing to accurately simulate, and MSFS2020 comes nowhere close. IMO, it has also been simplified to make it easier to fly. This is great for getting newbies into aviation. Hopefully, it will get better with time.

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