Realistic fly?

(…)it's just that i would not call that turbulence at all. i'd call that gusts. if you make them super strong, i'd still call them gusts, not turbulence. but maybe that's a language issue

I think I know what you're after, but remember gusts on the ground are turbulence in the air...

turbulence.

.

 

[ˈtəːbjʊl(ə)ns]

 

 

NOUN

.

 

violent or unsteady movement of air or water, or of some other fluid.

 

"the plane shuddered as it entered some turbulence"

 

synonyms:

 

rough air currents · irregular atmospheric motion · uneven air movement ·(…)

Turbulence is just where airflow is non-laminar - some parts of the air are moving in a different direction, and with a different velocity, to the average flow.

If a body of air with nonlaminar flow occurring moves past you - you'll feel gusts (puffs, zephyrs, whatever).

Gusts = turbulence like tomayto = tomahto.

The general approach of using gusts to model turbulence is common and has specifications set by the USDoD & the FAA. (& I just discovered MATLAB provide specs to replicate the most common approaches : Dryden model & Von Karman model).

This is roughly the approach we have now. Turbulence as a distribution of changes in air velocity.

The movement of the air is uneven, and the unevenness causes perturbations of the aircraft's flight - which is turbulence.

I assume DCS doesn't explicitly use either of the models mentioned above, as both provide fields that vary spatially, but don't vary with time - which wouldn't give the gusts in the video.

My guess is that there's a sampled temporal distribution of variance imposed across all space (so gusts vary with time, but not across space), but I've never tested for that.

What you appear to be asking for is 'white noise' movement. Flaming Cliffs and earlier used to model turbulence like I think you're asking for. Essentially it just added random shaking to the aircraft that was altitude dependant, and you could dial up or down the magnitude of the shaking.

With respect to flying the aircraft that white noise was essentially irrelevant. because it was randomised if you just held the stick in one place rigidly, the aircraft would move around a course by some amount, but on average take the course.

If you got set up for landing, you could feel it, but you could ignore it.

I'm not a pilot, but I have flown a light plane over the mountains of the Southern Alps on a day with light winds & felt that turbulence, I've flown a glider a few times over ridges and thermals, and I live in windy Wellington (& for comparison, Chicago - 'the windy city' has an average windspeed of 18km/h, Wellington's average is 29 km/h. Wellington has recorded 233 days of gale in a single year). I fly as a passenger in a Cessna Caravan reasonably regularly & larger planes quite frequently, so I get to experience turbulent landings & take-offs fairly frequently.

I think DCS does a reasonable job using the gust approach - it's definitely an improvement on the white noise they had.

Perhaps they could up the amount of short time period gusts to get a bit of 'rattling', but it's all CPU cycles, and what we have now gives you something you have to take account of - which is the more useful part for all of us that don't have but-kickers...

Fly the attached (land at Batumi), and as you go watch the triangle under the IAS on the HUD flicking between left (decelerate), middle (constant speed), and right (gaining speed).

You can't feel it, but that would be a bumpy ride.

Turbulence.miz

I think I know what you're after, but remember gusts on the ground are turbulence in the air...

Yes, i didn't want to imply that you're wrong. It's all turbulence, but "phenomenologically" they can be quite different. There is just a lack of words to describe it...both in german and english it seems.

I've got also some experience flying in smaller aircrafts, but i think what DCS lacks is more obvious when having a "bad" or bumpy flight in a jetliner. This heavy buffeting, like when driving fast over a very bumpy road.

It's either not modelled in DCS, or if it's modelled it does not convey it to the player audiovisually. I still suspect it's the first...

Interesting to read about original Flaming Cliffs "noise". I think such a solution could be useful in addition to the "gust" turbulence. And of course it would need to be localized - placed where it made sense by the atmospheric model.

I can't play your mission right now, but i will later.

Since you write, you can't really feel the bumpiness though it's there, maybe the model we have is already "fast" (bumpy) enough, but the modules(aircrafts) would need to give some audiovisual feedback to the player: That'd be mainly sound, camera shake (for non-vr) and physical interaction of loose cockpit parts, to show the buffeting.

To be honest, i think that the devs are aware (especially with that new GA sim showcasing all the nice weather and weather physics) and that we will get some higher fidelity buffeting (effects) and localized weather physics at some point in the future.

I will do some reading on the simulation models, you've mentioned. Sounds interesting.

i want to add, that i'm aware that flying in jetliners might emphasize those fast buffeting turbulence, because there is so much loose equipment "flying" around in the cabin: cutlery, baggage, fellow passengers without seatbelt on...

however, even in a military plane there are plenty of things that could rattle and rumble when shaken. i think some DCS modules already do show buffeting before stalling, which should be phenomenologically similar to "atmospheric turbulence buffeting". however i don't own one of those modules (f-14, f-18 f.e. if i'm not mistaken) yet.

how do those modules do the buffeting effect? i assume sound and camera shake?

how do those modules do the buffeting effect? i assume sound and camera shake?

Yes, both. Most turbulence is felt IRL however, not seen or heard.

Hello everyone. You do not believe that the behavior of airplanes in flight could be improved?. I think it is not realistic. I have piloted single-engine pistons and I do not say that the behavior must be the same, logically, but it does not seem to me that a fighter plane is immune to turbulence. I think that part is badly simulated. What is your opinion?

Given that the typical single engine prop A/C weighs around 2000 lbs (~900kg) while a typical fighter aircraft weighs anywhere from 25,000 to 45,000 lbs basic weight (~10,000 to 20,000 Kg) and flies 3-5x faster - you are not going to feel (see) the turbulence effects the same as in your light piston plane.

Given that the typical single engine prop A/C weighs around 2000 lbs (~900kg) while a typical fighter aircraft weighs anywhere from 25,000 to 45,000 lbs basic weight (~10,000 to 20,000 Kg) and flies 3-5x faster - you are not going to feel (see) the turbulence effects the same as in your light piston plane.

this is most certanly not correct. jetliners show very strong buffeting in "turbulence" and they are heavy and fast. i would assume that higher speeds even emphasize the tubulence, as the body of the aircraft is hitting harder against the turbulent airflow.

i could imagine that fighter aircraft show relatively less buffeting because of the higher wing load, but this is just an educated guess.

this is most certanly not correct. jetliners show very strong buffeting in "turbulence" and they are heavy and fast. i would assume that higher speeds even emphasize the tubulence, as the body of the aircraft is hitting harder against the turbulent airflow.

 

i could imagine that fighter aircraft show relatively less buffeting because of the higher wing load, but this is just an educated guess.

Wing loading certainly plays a part. But you are talking apples and oranges. I think if you took a Cessna 172 to 39,000 ft in a 100kt Jetstream + turbulence - it might feel a bit more "severe" than it would on an A380 in the same air mass. Just a guess.

All this talk about turbulence is interesting but the “turbulence” we used to have seems to be MIA. I set up a mission this morning with max winds and turbulence and barely felt anything. This was with the Su-27 that used to give me quite a ride in the past.

this is most certanly not correct. jetliners show very strong buffeting in "turbulence" and they are heavy and fast. i would assume that higher speeds even emphasize the tubulence, as the body of the aircraft is hitting harder against the turbulent airflow.

 

i could imagine that fighter aircraft show relatively less buffeting because of the higher wing load, but this is just an educated guess.

The Wing loading is the critical factor although speed does make a difference. In the 777 below 25K we fly at 270 kts, lower than our normal climb speed of about 320 to mitigate some of the turbulence effects. We still get thrown around occasionally if it's really bad.

In the Tornado we could actually change the wing loading by sweeping the wings back and this would make a significant difference to the felt turbulence, if you wanted to cruise smoothly at low level on a thermally day in the summer you could just put the wings back to 45 or 35.

Neither of these aircraft get thrown around like a 172 though which I remember could get thrown all over the place by relatively mild turbulence.

I still maintain that DCS does a pretty good job of representing this but then I fly with a jetseat and I know the F410 spent some time trying getting the feel right so maybe that colours my opinion somewhat.

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All this talk about turbulence is interesting but the “turbulence” we used to have seems to be MIA. I set up a mission this morning with max winds and turbulence and barely felt anything. This was with the Su-27 that used to give me quite a ride in the past.

When I was flying the mission I left above, I did think that while the aircraft was definitely getting thrown around & needed correcting, it was less violent than I remembered, but the gauges shoed the aircraft being knocked around....

When I was flying the mission I left above, I did think that while the aircraft was definitely getting thrown around & needed correcting, it was less violent than I remembered, but the gauges shoed the aircraft being knocked around....

Yeah, I tried your mission yesterday and have the same feelings.

I remember something like this:

Imagine to have in DCS

-Thermals

-Shear winds

-Up and Down winds in Mountains

-Weather based turbulences at any Altitude

etc.

Amazing :) Once that would be implemented its would be time to get a Pzl 104 as Tug a ground based winch and some Sailplanes as module released as well.

When I was flying the mission I left above, I did think that while the aircraft was definitely getting thrown around & needed correcting, it was less violent than I remembered, but the gauges shoed the aircraft being knocked around....

Just flew it for a few minutes this morning with the most recent OB. Nada. No turbulence felt and none evident on the instruments. Is there a certain altitude the turbulence begins?

Edit: I just re-read the post with this mission. I wonder if I didn’t wait long enough. I’ll have to try it again when I have more than just a few minutes to fly.

So I reflew Weta43's mission this morning with enough time to do it justice. There is indeed "turbulence", though it doesn't occur until about 300m AGL. Tried climbing to a higher altitutude first. Nothing. Not a hint. Headed in for the landing and, at around 300m AGL--maybe a bit higher--the aircraft started getting pushed around all the way down to the ground.

The interesting thing, however, is that there is no wind in the mission at those lower levels. The only wind in the mission--5 mps--occurs at 2000m and above. So the turbulance now seems to be tied to altitude, rather than wind speed as it always had been.

Imagine to have in DCS

-Thermals

-Shear winds

-Up and Down winds in Mountains

-Weather based turbulences at any Altitude

etc.

 

Amazing :) Once that would be implemented its would be time to get a Pzl 104 as Tug a ground based winch and some Sailplanes as module released as well.

Sent from my GM1915 using Tapatalk

Fwiw we have shear wind built in by default. If you load a 10 kt crosswind on the ground it will give you almost 20kts at 1600ft with a shear which you can't adjust unfortunately. It makes it somewhat unrealistic if you chuck in a 30kt crosswind as you get shear that would only occur maybe 5% of the time IRL.

 

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I remember testing this drastic wind change at 1600ft a while back. I set the surface wind to 25kts which almost doubled the value at 1600ft then I flew at 90 deg. to it descending from 3000ft to 500ft watching the VV on my HUD. It was close to the left side of HUD and when I descended through 1600ft there was no change whatsoever. No bump, no wobble and VV stayed put in the same spot. I think that change at 1600 is bogus.

@Ironhand: currently you can set tubulence without the winds up to the value 197 (used in the WindyTX's miz) and throwing around occur below 800m AGL.

@Gripes323: Last time I checked in F-14, which show me the wind speed right in the cockpit, the change between altitudes is gradual - not sudden.

So I reflew Weta43's mission this morning with enough time to do it justice. There is indeed "turbulence", though it doesn't occur until about 300m AGL. Tried climbing to a higher altitutude first. Nothing. Not a hint. Headed in for the landing and, at around 300m AGL--maybe a bit higher--the aircraft started getting pushed around all the way down to the ground.

 

The interesting thing, however, is that there is no wind in the mission at those lower levels. The only wind in the mission--5 mps--occurs at 2000m and above. So the turbulance now seems to be tied to altitude, rather than wind speed as it always had been.

Yes, I think the turbulence is calculated independent from - but cumulatively with - the wind - which I'd set to zero at all altitudes because I wanted to isolate it from the effect of wind / wind shear.

If I have time tonight I'll add 5.6m/s wind at altitudes and see if turbulence appears at higher altitudes.

Yes, I think the turbulence is calculated independent from - but cumulatively with - the wind - which I'd set to zero at all altitudes because I wanted to isolate it from the effect of wind / wind shear.

 

If I have time tonight I'll add 5.6m/s wind at altitudes and see if turbulence appears at higher altitudes.

You already had 5 mps at 2000 & 8000 m. I noticed no effect while climbing. The only turbulence I noticed was close to the ground.

@ Draconus: I was about to say that the highest turbulence I could set was 60 but then I realized I'm using metric and you're using imperial. :)

60 * .1 = 6 m/s = 21 km/h

Still not massive

60 * .1 = 6 m/s = 21 km/h

 

Still not massive

True. Roughly 6 m/s which is noticeable but easily managable. Of course, in the mission you posted with 5 m/s winds at 2000 & 8000, that becomes 30 m/s up there, yet you feel nothing. Nor do the instruments give any indication of turbulence.

Yes, both. Most turbulence is felt IRL however, not seen or heard.

This about says it, IP says take no action you fly into it and you'll fly out of it. It is more a seat of the pants experience. in my limited experience.

Now for motion feedback simpit. :helpsmilie:

This about says it, IP says take no action you fly into it and you'll fly out of it. It is more a seat of the pants experience. in my limited experience.

 

Now for motion feedback simpit. :helpsmilie:

yes, but it's quite usual for games and simualtors to substitute motion or haptic feedback with audiovisual feedback.

did you ever wonder, why you hear the switches in the cockpit "click". it's not that they are that loud in reality, are they?

or the camera shake in a racing game, when you are hitting bumps?

it works.

Agree, I have it so the helis really shake in and out of ETL even though it's not at that level IRL it's a good cue.

As for the switches you can't really hear them unless it's like the battery switch. :)

It would depend how it might be implemented hence motion feedback. :thumbup:

Curse this hobby $$$ (in a nice way)