[FIXED 1.13.17.0] World Update 3 has broken flight dynamics, exhibit A

A thrust value that is too high either due to sim programming error or input error on the part of the user. It is certainly possible to see the behavior shown flying a very lightly loaded aircraft with a small amount of extra power. I used to do this demonstration regularly in a variety of aircraft for flight training purposes.

As I’ve said many times so far, I’d rather people step back and look at this objectively and do real testing instead of jumping to conclusions based on one attempt at something. If you practice using different speeds and techniques, it might become apparent that technique was the issue. I’ve not had the time yet to test thoroughly, so I’m not calling it either way. I don’t really want to continue this discussion until I’ve done that because it seems that nothing short of a video to the contrary will convince people.

My approach speed was 85 knots indicated. Flared at about 90 thanks to the dive down the hill at the end. A bit fast at the flare but would still have expected a slight nose up and idle power to bleed off enoug speed to let me settle on the runway at some point, not float the whole way down. My approach was mostly at idle. From what others are saying, the problems aren’t as pronounced in the 152/172.

A real pilot told me today that physics are changing in the real world too. He had to ask the passengers to jump and up and down to bring the plane to land.
Asobo is completely right about the flight model heresy will not be tolerated in this forum, how can you say an A320 can’t climb with idle trust at 60 knots if you see it climbing with your own eyes? Do you see the eye of London? Would you say that is not there too?
Accept the facts not what a bunch of formulas and physics books tell.

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Re the thrust thing…my thrust was at idle as you can see from the gauges the the few times I pan the camera down to it and I don’t think they made thrust changes in the latest update.

I only posted one video as I thought I was indicative of the problem but I did many landings in different planes at different locations before I posted, I just posted the one I thought highlighted the problem best.

I did another test where I flew the St Barts approach low and level until the dive down the hill. Crossed the hill at 69 knots, idle power, dove down, flared at 73 knots and it took a nose down attitude to get it to settle onto the runway. Even then, full brakes and full reverse didn’t stop it in time.

Be great if you could report back with some thoughts when you get the chance to test and even better if you could report back with a video.

As a real world pilot, it only takes ONE attempt sometimes to know something is seriously wrong.

In real life, when an A320 is at 60kts airspeed at idle, it will be firmly planted on the ground. In the sim, it will be floating along the runway like a feather after the update. I don’t need to bring this data to an engineer to know this is not correct.

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Side-slipping and performing a crosswind landing is in essence the exact same maneuver, namely flying cross-controlled. Over the ground the effect might look different, but aerodynamically it is the same thing. Depending on where you live you might use the term “forward slip”, I have been an instructor for 5 years (in EU) and never heard about a forward slip until running into a similar discussion before on this forum. Side-slipping is a nice maneuver to practice during flight training (if approved) but otherwise its not a technique to be used in normal operation, if you are hot and high its safer to go-around. Side-slipping is not completely without risks.

It would be awesome if you could do that. I so far have flown the C152, Da-62, Pa-44 and have not found obvious flaws in the landing physics, e.g. no excessive floating.

RE:A320: It has been seriously broken since launch. I don’t even consider flying it because of how bad it is. I wasn’t expecting magic bullets this patch either. I’d rather focus on the aircraft that were close to or very accurate prior to the patch for me, which is the C152, C172, and Baron. Personally I think there are serious turboprop/turbofan modelling issues or perhaps issues with the airfoil aerodynamics for jets. I generally stick to pistons and the CJ4 with the WT mod because they are the most accurate from what I’ve seen.

If we’re discussing turboprops/turbojets, I would agree that they generally seem incorrect compared to the published data, but that doesn’t necessarily imply the simulator aerodynamics is wrong. It may be something inherent to those aircraft (considering they share the same type of powerplant, I suspect that is related).

The point being that a change to the simulator aerodynamics in a patch isn’t going to necessarily fix something that was previously already broken. If anything, it might exacerbate underlying issues. It is not indicative of the change itself being positive or negative, but could instead indicate how poor the original flight model of that aircraft was from the start.

Maybe this answers the question:

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Indeed. I would suggest that the forward slip should only be performed in an emergency where a go-around is not possible (powerplant failure for instance) and excess energy must be bled without a turn because it is, by nature, an unstabilized approach. There are probably some random scenarios or emergencies I’m neglecting, but for normal operations I’ll stand by this statement.

So let’s pretend that the OP did have an emergency and had to land at St Bart’s. If a very slow approach with full flaps still doesn’t get him down, a creative pilot might try slipping and even raising flaps. If the plane is truly broken right now, that sounds like a fun challenge to me!

Have fun with the Kingair, I have flown that one in real life. Its easily the most hideous flight model in the whole simulator. There is just no propeller drag modeled on that thing, it doesn’t decelerate and floats like a Russian ekranoplan in ground effect :joy:. And then someone at Asobo thought it would be a good idea to come up with a landing challenge where you are tasked with landing the Kingair at Saba :neutral_face:. On a positive note they could extend the runway now over the big pile of Kingairs accumulated at the end of the runway…

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I wouldn’t raise the flaps, that is gonna work counterproductive. It might help to raise the flaps after touchdown to transfer more weight onto the wheels and increase brake efficiency but otherwise keep the flaps in landing position. Regarding steep approaches, apparently full flaps and gear down and power idle is insufficient in MSFS in the current state so there isn’t really anything left to do except slipping…

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Yeah, it seems that way to me too. The PT6’s flat plate drag when at flight idle is absolutely horrendous in both the C208 and King Air. I have used that to good and bad effect IRL. Getting a little too aggressive with a power reduction in the Caravan on short final nearly went very poorly for me for that exact reason. Luckily, the power comes on quick with turboprops. The sim doesn’t offer the same sensation of deceleration, but I’m somewhat confident the knots fall away much faster in real life.

I meant to fly the short final as slow as possible with full flaps and slipping, then do the equivalent of deploying spoilers by raising flaps a notch. That would cause a loss of lift in the sim, and since drag isn’t realistically modeled, it should cause you drop into contact with the runway without and undue increase in speed. That’s my theory.

Of course in real life, raising the flaps would decrease lift but would also decrease drag. It would probably equal out and not do you any good.

But you need the drag, landing flaps produce more drag than lift. I’m not sure if this would work, on the other hand, I guess anything is possible in MSFS at this point so go for it :joy:. In real life it is not gonna equal out, you lose a lot of drag and some lift, initially the aircraft will sink and pick-up speed, also stall speed goes up so in real life definitely not a good idea.

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Can someone built this thing for MSFS? It seems like the current flight model does support such a vehicle :joy: :joy: :joy:. Only need the visual model, for the flight dynamics just copy the TBM .cfg file :wink:.

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Regression & Integration testing it appears are very much non-existent since the beginning of this project. To me it feels like how I used to code in the 80’s and 90’: “Eh, it SHOULD be good, I only made a small change.”

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There is a say in Software Development: If you do something, do it right!

Saying the truth has nothing to do with a negative attitude. I can only speculate why these things happens @ASOBO. In my experience it has to do something with their DevOps model.

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Ground effect is gone by about 1 wingspan in altitude (50 feet for the C208)

Over the ocean, at an altitude of 200 feet, clear skies, 0 wing, with Flaps 2 and 38% throttle you can now fly the C208 straight and level at like 30 knots.

This is not right. It’s about half the stall speed. It’s well above where any ground effect would occur.

It seems like some aircraft are more impacted then others. The TBM930 also seems floaty. The DA62 does not, but this patch addressed a static thrust bug that was specific to the twin prop aircraft so maybe the DA62 received more attention in the patch as part of fixing that bug, and hence is now better retuned for the flight model changes.

I’ll reiterate again that having versions of the flight model and allowing aircraft to call whichever version they were tuned against is the only sensible solution to this issue for a sim that is supposed to last 10 years.

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