A-10 stall behaviour in DCS is incorrect

[David OC]

IRL Pilot,

 

"Interesting stuff. Thanks for the info. So, the next question: is the indicated ITT accurate or do we simply have a faulty pair of ITT gauges? On a standard day, with the power levers set to MAX, are we generating the expected fan speed and is the engine producing a realistic thrust output?

 

This situation isn't unique to DCS World. Back in the day I used to play a lot of Warbirds and there was constant bickering with the developers and players over flight modeling of various planes. Sometimes it would get pretty heated."

 

----

 

Beta tester,

 

"I'm not sure, but I think thrust is likely correct but ITT is incorrect. Those who have tested aircraft performance in DCS have, to my knowledge, said that it matches the E-M diagrams closely.

 

"I have taken single data points here and there, such as maximum level flight speed, and noted slightly deficient performance. But that could be caused by many things besides insufficient thrust."

 

Edit

We don't need to go back down this road do we, lol.

 

Anyway, just my 2 cents.

 

-

Edited May 24, 2017 by David OC

[Gliptal]

Then the ITT should indicate the correct value.

[David OC]

The power is still correct to hit all the flight parameters, this gauge is in range with the data available, as seen in the links below.

 

https://forums.eagle.ru/showpost.php?p=2868802&postcount=117

 

and the next post.

 

https://forums.eagle.ru/showpost.php?p=2868806&postcount=118

 

If you have better access to information about programing this, then please share it so it can be modeled.

[Dino Might]

Is the testing done under similar loadouts? I, personally, am an offender with the TERs and the LAU-88s running a**loads of boom boom, so I am never too surprised when the occasional tip stall or dutch roll occurs.

[mytai01]

I honestly think the stall behavior is a little too sensitive. This video seems like the A-10 is a little less sensitive than the DCS flight model:

 

[Kippy]

mytai01, I agree. Check out JasonXD's post towards the top-mid of page 8.

 

...when the real A-10C pilot had a Q&A (and I think another, or few other pilots), he/they mentioned that the real plane is definitely more forgiving in high AoA and also had more powerful engines than the one modeled in the sim.

 

 

However, I would much much rather have the aircraft be a little more unforgiving rather than being more forgiving than the real life counterpart. :)

[SCU]

However, I would much much rather have the aircraft be a little more unforgiving rather than being more forgiving than the real life counterpart. :)

 

Given a choice between limitation and a little extra, as compared to real life, I would chose the extra all the way (in a sim no less). Of course I would much, much, unimaginably much more that we get an accurate simulation, neither extra nor limited, but spot on, which by the way is the case with countless other systems & behaviours in the A-10C ;).

[mytai01]

The real A-10 has much snappier flight performance than in the game. quicker rolls, pitch ups, and higher alpha without rolling to one side. It would be nice to see the vapor over the wings...

[NineLine]

The real A-10 has much snappier flight performance than in the game. quicker rolls, pitch ups, and higher alpha without rolling to one side. It would be nice to see the vapor over the wings...

 

Based on??

 

Vapor over wings is on the Todo list.

[cichlidfan]

I honestly think the stall behavior is a little too sensitive. This video seems like the A-10 is a little less sensitive than the DCS flight model:

 

 

Let me give you an example of why watching a YouTube video is not a good reference. How much fuel is in that aircraft?

[mvsgas]

I do not know if the model is correct or not. But, If I may add to cichlidfan post:

mytai01,

In order to compare the RL aircraft to DCS, I think we would need more details that the video you have posted several times. For example weather conditions on the airport where the video was film. Wind speed, altitude, temp etc.

 

Then we need more details on the aircraft within the video. What is the Empty weight, drag factor, etc.

For the aircraft configuration (fuel, etc.) We can use the AFI 11-246 (direct PDF link http://static.e-publishing.af.mil/production/1/af_a3/publication/afi11-246v1/afi11-246v1.pdf) but we will ultimately need to know the specifics of the aircraft in the video.

 

We also would need a HUD video of that specific demo.

 

Finally, we need to see of we can match the numbers in DCS. If we can't get the same drag factor, we already could not compare it. If we can't get an Airfield at the same altitude or the same weather, we can't compare it. And we need to decide which version of DCS we are comparing.

[SCU]

In order to compare the RL aircraft to DCS, I think we would need more details that the video you have posted several times. For example weather conditions on the airport where the video was film. Wind speed, altitude, temp etc.

 

Here are some videos (including HUD tapes) I shared at the start of this thread that no one cared to watch and just jumped on the what-is-this-heresy bandwagon (jk lol.. well, kinda :smilewink:)

 

 

Try the maneuver between 0:29 & 0:41, which is a solid 12 seconds of chopped stall tone, in DCS. You can try it with the lightest weight possible, clean config & the most ideal conditions and you will lose.. you will lose control and your wings will keep droping.

 

Granted this A-10 has a decent amount of fuel (obviously so he can RTB after training) and carries 1 AIM 9 at least.

 

.

(Cockpit)

 

(External view of the same maneuver)

 

These videos are from airshows as you can see, the jet is obviously clean & probably on minimum fuel for top performance.

 

-

 

You can see how the plane is jerked with a buffeting behaviour and no wing drop or rolling which is how it's described in the manual (so shameless of me :lol:). This would probably work with the light weight setup in the sim, but only because it's a sudden move and doesn't give time for the wing dip coding in the flight model to set in or something, I'm not a coder I don't know, but trying to sustain it you will definitely lose control. If the plane IRL rolls on higher than critical AoA's I don't think the pilot would risk such a move at such low altitude close to watchers.

 

(HUD tape)

 

Brief hard pull up, but you can see if you look closely how as the chopped tone sets in there is buffeting of the airplane and only that.

 

Buffeting is more clear here:

 

I counted about 9 seconds of chopped tone in this one. I don't think that's possible in DCS with perfect conditions and lightest configuration. You even don't get any stall tones at the airspeeds in this specific video (above mach 0.7) with the same pull, you just spiral out of control until relaxing the stick.

 

(I'd lower the headphones volume before watching)

The first 12 seconds or so are mostly riding the chopped tone at slow speeds, again unlike in DCS, no wing stall or dropping. Also this is a combat operation recording, I don't know how that makes a difference but I thought I'd let you know. The fuel is really low (13:45, below bingo) as you'll find out as you watch the video later on (it's 20 mins long).

 

I'm not sure if weight should affect stall behaviour directly. Genrally (shameless plug i know) you should read the stall & departure sections clearly from the manual and pay attention to the details talking about sideslip and yaw-roll coupling.

 

There's still more videos where those came from, I haven't shared the dogfight ones yet

Edited August 9, 2017 by SCU

[SCU]

The real A-10 has much snappier flight performance than in the game. quicker rolls, pitch ups, and higher alpha without rolling to one side.

 

This is kinda shown here:

 

 

 

Try the maneuver between 0:29 & 0:41, which is a solid 12 seconds of chopped stall tone, in DCS. You can try it with the lightest weight possible, clean config & the most ideal conditions and you will lose.. you will lose control and your wings will keep droping.

 

Granted this A-10 has a decent amount of fuel (obviously so he can RTB after training) and carries 1 AIM 9 at least.

 

This video I believe, is the total package when it comes to showing the shortcomings, so to speak, of DCS's A-10C flight model, I implore everyone who wishes to discuss in this thread to watch this one first.

 

Sorry for double posting.

[David OC]

Have you tried to fly the A10 like that in the video, with 1500 fuel, no weapons or gun ammo on board?

 

Give it a try in game, she's quite maneuverable then.

 

Ok, perhaps it has the AIM-9 training missile under the wing.

 

EDIT. Will try and do a few tests on the weekend with the lightest weight possible in standard conditions.

 

.

Edited August 9, 2017 by David OC

[SCU]

Yes I have, hence the thread and my arguments. My computer isn't the strongest so recording a video isn't a good idea, and I have been away from DCS for quite a while, but I have definitely tried to do those maneuvers before on a clean jet and still getting the adverse effects.

 

I have shared videos which were of combat operations, the A-10s in said videos were heavier and with weapons and gun bullets loaded as opposed the clean A-10s I tried, they still ride the choppy tone like it was nothing..

 

Now I feel like a robot, repeating my self and answering the same questions over and over :P, you're so skeptical guys.

 

Edit: Im aware I can post a track, but as I said, I've been away from DCS for months, I would need to dust off my hotas and my rust to make a track, but I believe a better option would be a video, where anyone anywhere can see it (@David or anyone).

Edited August 9, 2017 by SCU

[David OC]

What controls do you use? Are you pulling to much G? We don't get the real G's on our body or proper feel from the IRL a10 controls, so watch the G meter very carefully when performing any aerobatics.

 

I will try and have a play on the weekend.

 

.

[SCU]

What controls do you use? Are you pulling to much G? We don't get the real G's on our body or proper feel from the IRL a10 controls, so watch the G meter very carefully when performing any aerobatics.

 

I will try and have a play on the weekend.

 

.

 

We had almost the same discussion about a year ago (the first & second pages of this thread), you can see that I replied to you with a link to a video of some guys (not pilots) trying out the A-10 simulator in an Airforce Base if I remember correctly, they were pulling crazy G's and going into the choppy warning tone without the adverse effects. Apart from that, I do watch my G's and I try to be careful as much as possible not to pull too much inside of the choppy tone, but whatever amount of care I put, to no avail..

 

And I use a thrustmaster warthog hotas.

[mvsgas]

SCU,

Same thing with all those videos. We need more details on each specific video. For example, using this link:

Creating a quick mission in DCS 1.5, I could not achieve the 270+ speed shown in the HUD at the 13000 altitude (max I got was 265), change the temperature and easily exceeded that speed. So just in that factor (speed) did I have the ambient temperature wrong or do we have a different drag or weight?

 

In DCS (with -15C temp, 3500 fuel, minimum chaff and flare, no gun ammo, One Cap-9 and one ALQ-131) I can do a 360 turn with chopped tone if I keep my nose down. But I have no way of telling the configuration of the aircraft in the video to compare it.

[SCU]

That's why I said to always try and match this video in the cleanest aircraft in the most optimum weather conditions possible (optimum means the least conditions that adversely affect high Alpha maneuvers, or better: even not at all).

By the way, note that the A-10 in said video only got above 270 speeds while sinking (descending) at a high rate.

 

Can you share a video of this 360 turn in chopped tone?

[SCU]

Also note that "all these videos" are most probably different A-10s in different locations with different conditions, it just can't be a series of coincidences that all of the videos had the perfect conditions to be able to ride the critical AoA, it is the very reason that I shared many videos not just one or two, to overcome the limitation of not knowing the conditions these A-10s were in.

 

The A-10C (and A) Dash one backs me up alongside the videos..

[mvsgas]

Can you share a video of this 360 turn in chopped tone?

 

Tell you what, give me a track showing the problem and I will make a track of the 360 degree turn with chopped tone.

[NineLine]

Tell you what, give me a track showing the problem and I will make a track of the 360 degree turn with chopped tone.

 

 

We do need to see a track of the issue to test internally. Just saying it's not right doesnt really do anything for ED.

[mvsgas]

 

LOL, Am I the Good, The bad, the ugly or the...what is the other name for cats?

[SCU]

Sorry man, I can't currently. Haven't played DCS for months now, I'm rusty, my hotas are dusty and DCS isn't updated even. I intend to come back again at the end of this month so if you're still interested by then maybe we can share tracks but for now you can try what the A-10 driver did in the video and see if you can reproduce what he did without having a wing drop, and post a track or video. Maybe I can update DCS to look at the track but I won't be sharing any from my side at this time, sorry ;).

[SCU]

I did post a track by the way, at the start of the thread in the first page or second, one minute and I'll link all ya's to it.

 

Edit: bear in mind that was me trying the airshow stuff not the dogfighting err.. stuff.

Complete with split S at low altitude & crash in the end. It did show some uncommanded roll before the crash.

 

Note all the uncommanded rolls throughout the track. Like I said, some of the sudden jerks will not go out of control due to their fast and brief nature.

 

http://forums.eagle.ru/attachment.php?attachmentid=146945&stc=1&d=1472063835

 

Conditions:

http://forums.eagle.ru/attachment.php?attachmentid=146946&stc=1&d=1472064169

Edited August 9, 2017 by SCU