Unrealistic turbulence effects

[bluepilot76]

I was doing a mission, that I had edited by setting the weather to Dynamic. The mission editor showed fairly light winds in the vicinity of Batumi etc.

 

Batumi ATC reported something like winds 180 at 3m/s. By my reckoning 3m/s is about a 5knot wind, which is nothing, from any direction. No problem I think, but my takeoff is so crazy that I think I must be taking off with half of the plane missing. Minus one tyre I stagger into the air. HUGE turbulence below about 300feet.

 

Then I go a about my mission. Air to Air refueling in the nice and smooth conditions of the upper air. I decide to land at Sakumi (sorry if the spelling is wrong; going from memory). ATC reports wind 3m/s at a heading I cant remember but basically 90 degrees of the runway and from straight out to sea, Sakumi is sort of parrallel with the beach. Anyway 3m/s, I think "small crosswind, no problem".

 

First sign of trouble, to maintain the runway centreline on approach, I have a huge drift angle, I imagine 15 -20 degrees or so. From the default head position, the runway was hidden behind the forward window frame, the part where the compass is. I had to use the quarter window, if thats what its called, BTW I love Track IR... "Seems like more than 3m/s" I think. Then as I get lower the whole aircraft starts ballooning probably 50 -75 feet or so. Large pitch corrections having little effect on vertical speed. Probably pitching down 10 degrees below normal approach angle, the plane was still trying to climb, and then drop. I made it onto the runway burst my remaining tyres, was lifted off again and stalled into the grass. Massive fireball. I would have ejected but I was so amazed by these horrendous forces affecting the aircraft that I forgot all about it.

 

Now Im all for a bit of turbulence, but there must be something wrong here. The A-10C is a heavy aircraft, plenty of momentum. It is not a paper aeroplane or 1 seat glider. 3m/s crosswind should not cause this effect. It felt like being in the rotor behind the mountain, during a hurricane (not that Ive ever done that, but I have landed in 50knots of wind before and there was the odd bump but nothing too exceptional, although that maybe due to the excellent pilot I was flying with, in a King Air). Anyway, the wind was coming off the sea, across a few trees, but nothing too severe. But at 3m/s? I dont think so.

 

So, either ATC is wrong about the strength of the wind; quite likely considering his efforts at reading the pressure, or the low level turbulence effects in Dynamic weather are a "bit" strong. Possibly I misheard the tower, but like I said at the start, the wind arrows indicated light winds at Batumi, and Im sure they weren't much stronger at Sukumi.

 

I REALLY like the idea of Dynamic weather, but this doesnt seem right to me. Noone would have been flying on a day like that, not even the ducks.

[EtherealN]

Do you have a track file and the miz file?

[bluepilot76]

Hi EtherealN,

I am sorry to say I havent got to grips yet with recording or playing back tracks. It was something I am going to investigate today. Will it still be on my computer? However I have flown the same mission again since then, but hadnt saved the weather from the first flight and regenerated it again.

 

The mission was Aerial Refuelling Training by Aylward, currently on the missions and campaigns board. Thanks Aylward!

 

I had edited it by adding an F16, (just to see how it worked), changing to dynamic wather, putting in a couple of cyclones, pressing generate a couple of times untill the wind arrows looked reasoneable, added a fog layer with 1000m visibility up to 300m. In the mission briefing I had changed the weapons loadout and reduced to 25% fuel. I took on several thousands pounds from the tanker, but jettisonned my stores prior to landing.

 

I will try and generate a similar scenario tonight and see if I am still shocked by the turbulence, I will let you know either way how I get on. Hopefully I will figure out this recording tracks business this afternoon.

[EtherealN]

Saving tracks is easy: after flight, you'll find a button at the debrief screen named "Save Track". Click that and it'll save a trk file to C:\Users\XXXX\Saved Games\DCS Warthog\Tracks.

 

To attach it, just select "go advanced" below the reply box, select the paperclip icon in the toolbar, and locate and upload the file there.

 

Same procedure for the miz (mission) file, except it's saved in Missions rather than Tracks.

[Irregular programming]

Hi EtherealN,

I am sorry to say I havent got to grips yet with recording or playing back tracks. It was something I am going to investigate today. Will it still be on my computer? However I have flown the same mission again since then, but hadnt saved the weather from the first flight and regenerated it again.

 

The mission was Aerial Refuelling Training by Aylward, currently on the missions and campaigns board. Thanks Aylward!

 

I had edited it by adding an F16, (just to see how it worked), changing to dynamic wather, putting in a couple of cyclones, pressing generate a couple of times untill the wind arrows looked reasoneable, added a fog layer with 1000m visibility up to 300m. In the mission briefing I had changed the weapons loadout and reduced to 25% fuel. I took on several thousands pounds from the tanker, but jettisonned my stores prior to landing.

 

I will try and generate a similar scenario tonight and see if I am still shocked by the turbulence, I will let you know either way how I get on. Hopefully I will figure out this recording tracks business this afternoon.

 

Just click the save track button on the mission result screen after your mission. :)

 

edit: too late, and a better explanation provided by eternal.

[bluepilot76]

OK wilco. There is a track on the boards at the moment that I want to watch, so hopefully I will get an idea about what recording a track provides the watcher with.

[EtherealN]

Yes - to load and view a track previously recorded or downloaded, simply select the "replay" function in the single player menu and navigate to the Track file. You can also take control mid-flight through the Esc button, if you so desire.

 

(The track is basically a recording of every command that happens, player and AI, letting me run exactly the same flight on my computer. Very good for both performance benchmarking and for replicating bugs. And of course invaluable for checking if there is a simulation malfunction or user error involved, since we can very easily see what was and what wasn't done without having to ask about every single detail. :) )

[MasterZelgadis]

Turbulences are not only affected by wind and wind direction. Turbulences are airflows in the up or down direction. Mainly they are produced by clouds, especially cumulus clouds, where the air is flowing upwards. Outside the cloud the air is flowing downwards.

I think thermal effects also play a role.

 

Don't know how well this is modeled in the sim, but could explain your turbulences while having nearly no wind.

[159th_Viper]

EtherealN

 

Fly this mission in 1.1.0.7. quickly - you'll quickly see what blue is referring to down low - it's like a Rodeo-Ride :D

 

http://forums.eagle.ru/showpost.php?p=1168545&postcount=1

[EtherealN]

Rgr that. :)

[bluepilot76]

Affirm on the thermals argument, except that the effects would be realistic for a paraglider, or an A-10C in s supercell storm cloud. Besides I had the temp set at -5 or something because I was hoping for snow, and thermals would not be so strong in those conditions, and the clouds were just small ones up at 6000 feet or so.

 

Thanks for the info on the tracks playback!

[Preacher]

Now I'm wondering if windshears are emulated in this game. Anyone know?

[EtherealN]

Ahah, yeah, that was... interesting. :P

[bluepilot76]

Track please EtherealN... Dont be shy!

[congo]

Turbulences are not only affected by wind and wind direction. Turbulences are airflows in the up or down direction. Mainly they are produced by clouds, especially cumulus clouds, where the air is flowing upwards. Outside the cloud the air is flowing downwards.

I think thermal effects also play a role.

 

Don't know how well this is modeled in the sim, but could explain your turbulences while having nearly no wind.

 

The updrafts are not produced by the Cumulus cloud. The cloud is a result of the upflowing column of air carrying moisture and debris aloft. The upflow is produced by heating of the earth and subsequent heating of air. Downflow is produced by cooling of the column.

[bluepilot76]

Got the tracks working - Thats a great system!

[MasterZelgadis]

Ah, yes of course. That's what I wanted to say actually, but while writing, I turned it around ..

 

Got the tracks working - Thats a great system!

Yes it is :)

But note that the tracks are not a video or such a thing, they are more a record of your inputs, that will be re-done when replaying it. That's why some replays end in the airplane crashing into the ground, after a patch with edited flightmodel. Watch some of the Ka-50 trick flight replays in Black Shark 1.02, then you know what I mean ;)

Edited April 19, 2011 by MasterZelgadis

[EtherealN]

Track please EtherealN... Dont be shy!

 

The prettiest landing in history! :D

whopseedaisy.trk

[bluepilot76]

Hi EtherealN,

Well you know what they say, any landing you can walk away from is a good one! I was definately not able to walk after my landing!

 

But that looks very similar to the experience I had, if anything slightly less turbulent, but maybe you just handled it better. What I dont know from watching the track is what the wind was supposed to be. In RL, I would imagine that was a 35kt+ crosswind, and very gusty at that. Which I'm sure would be out of specs for most aircraft.

 

Looking forward to having a go myself!

Cheers

[EtherealN]

Hi EtherealN,

Well you know what they say, any landing you can walk away from is a good one!

 

Wise words given by all instructors. Mine did however also insist that I at least try to ensure the plane can fly again. :D

[bluepilot76]

Well yours could have, if you hadnt used the yellow and black door handle! Pity you cant get out another way....but thats a different thread...

 

So what was the wind supposed to be? Do you think there might be a little adjustment necassary?

[EtherealN]

Yes, that does look like it needs a bit of tweaking. I need to test it in the testing builds first though to see if it's already fixed. :)

[jeffyd123]

Ive created a mission with dynamic weather and a 4m/s turbulence setting. the landings at Sochi adler @ runway 24 were weird... every single landing, no matter how well done always resulted in 2 or 3 blown tires...

But, landing at 06 resulted in no blown tires.

 

Im sure it has something to do with wind direction but it seems to me that there is too much turbulence and crosswind activity in dynamic weather.

 

the .trk is 32 meg so i cant upload it... there were 6 MP pilots in the session and all had the same results.

[VF31_Subsonic]

Wise words given by all instructors. Mine did however also insist that I at least try to ensure the plane can fly again. :D

 

That is always a good thing...less paperwork

[EtherealN]

the .trk is 32 meg so i cant upload it... there were 6 MP pilots in the session and all had the same results.

 

Try zipping it using an aggressive compression setting.