Jump to content

Wings snap at low g's


BlackPixxel

Recommended Posts

Hi,

 

when flying fast (in the following case 1.4 mach) the wings of the Su-33 appear to become very brittle. They will just brake off at rather gentle g loadings.

 

Here they snap at 5.2 g's:

 

Is this intentional? It seems more like a wrong config, and it only happens hat higher speed. At low speed the plane can handle the g's at you would expect.

 

When accelerating and reaching a certain speed, the plane starts to do a sudden pitch change and the trim is off. Maybe this is the speed at wich the wing snap mode is initiated?

Link to comment
Share on other sites

I wouldn't call 5G turns gentle. Was the Automatic Control System off? How heavy you were?

There is the speed region where it's not possible to control pitch by trim alone but it shouldn't be relevant.


Edited by draconus

🖥️ Win10 i7-10700KF 32GB RTX3060   🥽 Rift S   🕹️ T16000M HOTAS   ✈️ FC3, F-14A/B, F-15E   ⚙️ CA   🚢 SC   🌐 NTTR, PG, Syria

Link to comment
Share on other sites

I wouldn't call 5G turns gentle. Was the Automatic Control System off? How heavy you were?

There is the speed region that is not possible to control pitch by trim alone but it shouldn't be relevant.

 

What would you call a gentle turn in combat situation ?

 

As we know @Mach 1.3 we still within the aircraft G factor limitations of 6.5G.

[sigpic][/sigpic]

 

I7 7700K@5.2GHZ+ NZXT X62 AIO Water cooling MSI Z270 Gaming M7 + CORSAIRE VENGEANCE PRO 16GB @3200MHZ DDR4 + MSI GTX1080ti gaming edition+ SSD SAMSUNG 850EVO PRO 128 Go + SSD SAMSUNG 850EVO PRO 240 Go + HDD SAMSUNG 1 To+ HDD SEAGATE 3 To

Asus ROG Swift PG348Q / Oculus rift

Case Coolermaster Mastercase 6 + CORSAIRE RM750W

Thrustmaster Hotas Warthog +Logitech G rudder pedals

Link to comment
Share on other sites

Hi,

 

when flying fast (in the following case 1.4 mach) the wings of the Su-33 appear to become very brittle. They will just brake off at rather gentle g loadings.

 

Here they snap at 5.2 g's:

 

Is this intentional? It seems more like a wrong config, and it only happens hat higher speed. At low speed the plane can handle the g's at you would expect.

 

When accelerating and reaching a certain speed, the plane starts to do a sudden pitch change and the trim is off. Maybe this is the speed at wich the wing snap mode is initiated?

Out of curiosity, had you already been pulling high Gs numerous times in that aircraft (assuming you were online and not taking a fresh aircraft each time). I ask because aircraft fatigue is modeled and, so, if the airframe was already severely stressed, it's possible to break something at lower Gs.

 

Also, when this issue had appeared in the Su-27 many moons ago, people were posting Tacview files/videos and it turned out that the in-cockpit G-meter was showing roughly 8 Gs when Tacview report was only showing 5 or 6. Just saying. Did you notice them coming off with a 5G reading in the cockpit or was it only later that you saw 5 Gs and thought WTF, there's a problem?


Edited by Ironhand

YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg

 

_____

Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0.

Link to comment
Share on other sites

A fresh aircraft is taken everytime its not the same aircraft, You only have to pull slight and the wings fall off, Maybe because they fold lol, But maybe tacview thing?

OK. Can somebody provide a short track? I just spent some quality time in the -33's pit boring holes through the sky. I was only able to take the wings off once and that was by exceeding the G limits for gross weight/Mach>1.25. Well, actually, those were for the Su-27 but I don't have the real-world manual for the -33. Hopefully those numbers are close enough.

YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg

 

_____

Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0.

Link to comment
Share on other sites

MIROO would be best to ask, Ill ask and post here.

 

OK Thanks.

 

...

 

As we know @Mach 1.3 we still within the aircraft G factor limitations of 6.5G.

 

Ummm. Where are you getting that G number from? Based on BlackPixxel's description of the situation, it'd be closer to 5.4, wouldn't it? But, again, that's based on the Su-27 manual as I don't have the manual for the Su-33. If you have it, would you mind sharing?

YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg

 

_____

Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0.

Link to comment
Share on other sites

It does indeed seem to be a fatigue thing. In the example I showed in the video at an earlier point 10g where pulled.

 

But it is still very fragile: In this tacview with a fresh plane with 4xER, 2xET, 2x73 and 2xECM with 50% fuel the maximum g loading was 7.7 for a short time. Then after releasing and pulling again it snapped at just 5.7g.

 

One other thing: In the Su-27 it is impossible to snap wings by pulling hard, because the g limiter is working everytime at any speed.

In the 33, the g limiter fails to work at high speeds. The plane is pulling as if override was enabled and just breaks appart as a result.

 

I am thinking whether the code behind the g limiter of the DCS Su-33 may just be a copy of the limiter of the 27, without taking the changed flight model into account (for example the 33 follows inputs on pitch much more aggressive than the 27 in DCS)

Tacview-20190318-191649-DCS_.zip.zip

Link to comment
Share on other sites

...

But it is still very fragile: In this tacview with a fresh plane with 4xER, 2xET, 2x73 and 2xECM with 50% fuel the maximum g loading was 7.7 for a short time. Then after releasing and pulling again it snapped at just 5.7g...

 

That 7.7 would be about 1.5 times the max allowable for your gross weight (roughly 28,000 kg) for M>1.25. If that was the case...but I don't know if your airspeed was up there.

 

...

In the 33, the g limiter fails to work at high speeds. The plane is pulling as if override was enabled and just breaks appart as a result...

The limiter was working just fine for me this morning from M1.0-1.35. Keep in mind that, if you jerk the stick, you can exceed the limits before the limiter can kick in. This is true in the Su-27 as well.

 

I am thinking whether the code behind the g limiter of the DCS Su-33 may just be a copy of the limiter of the 27, without taking the changed flight model into account (for example the 33 follows inputs on pitch much more aggressive than the 27 in DCS)

I doubt anything was done with a simple copy/paste. Not saying that there might not be issues. But I haven't observed them myself in admittedly limited testing.

 

I'll check your Tacview when I can. Might not be today, though. Do you by any chance have the TRK file, too?

YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg

 

_____

Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0.

Link to comment
Share on other sites

The speed was at M1.4

 

Even when pulling very slow at high speed the g indicator will go to the limit and the plane falls appart.

 

The 7.7g peak may have been over the limit, but will it cause the plane to fall apart at the next 5.7g pull or will it just mean that the lifespan is shortened a bit?

 

 

(I am aware that the F-15 is a completely different plane, I just found it interesting: With full tanks, 3 fuel tanks + AIM120's on the remaining stations I do one 11.5g pull after another with 12.5g peaks in between until the tank is empty. No damage, even though I pull over the 9g's with such a heavy load over extended periods)

Link to comment
Share on other sites

The F-15C doesn't have a g-based damage model.

 

While it can survive more g, that kind of loadout should break the aircraft at 7-9g, I don't recall the exact number.

 

 

Edit:. I thought you had 3 full tanks. Empty tanks aren't that heavy.

[sIGPIC][/sIGPIC]

Reminder: SAM = Speed Bump :D

I used to play flight sims like you, but then I took a slammer to the knee - Yoda

Link to comment
Share on other sites

The tanks where selected in the editor, so they where full (I assume, I have no experience with the F-15).

 

What I meant is that I can fly and keep doing crazy stuff with full afterburner until no more fuel is left.

 

I am no longer suprised that my ER's have such a low hit ratio after seeing how this plane can be thrown around.

Link to comment
Share on other sites

I was going to say that the F-15 has its own issues with Gs but GG got there first. The thing can be a real flying saucer. :)

 

Do you by any chance have a track you can share?

YouTube Channel: https://www.youtube.com/channel/UCU1...CR6IZ7crfdZxDg

 

_____

Win 10 Pro x64, ASUS Z97 Pro MoBo, Intel i7-4790K, EVGA GTX 970 4GB, HyperX Savage 32GB, Samsung 850 EVO 250 GB SSD, 2x Seagate Hybrid Drive 2TB Raid 0.

Link to comment
Share on other sites

  • 7 months later...
  • ED Team

If anyone can get a short track replay showing this we will be happy to take a look.

 

thanks

smallCATPILOT.PNG.04bbece1b27ff1b2c193b174ec410fc0.PNG

Forum rules - DCS Crashing? Try this first - Cleanup and Repair - Discord BIGNEWY#8703 - Youtube - Patch Status

Windows 11, NVIDIA MSI RTX 3090, Intel® i9-10900K 3.70GHz, 5.30GHz Turbo, Corsair Hydro Series H150i Pro, 64GB DDR @3200, ASUS ROG Strix Z490-F Gaming, HP Reverb G2

Link to comment
Share on other sites

Thank you for taking a look at the issue!

 

I uploaded two trackfiles that provoke the wing snap by going very fast and pulling without overwriting the g limiter. Still the Su-33 pulls more g than it can handle and loses its "paperwings".

 

I see two issues here:

The limiter should not allow the Su-33 to pull more g than the airframe can handle, and the stress damage seems overdone. Especially compared to other ED DCS modules that are able to pull 12.5g with full weapon loadout and full external tanks forever.

Su-33.trk

Su-33_2.trk

Link to comment
Share on other sites

  • 3 weeks later...

Is this issue being investigated?

 

I uploaded the requested tracks in a previous post:

https://forums.eagle.ru/showpost.php?p=4087461&postcount=18

 

The G-limiter does not limit the G-load properly when flying with some speed, especially when the plane is equipped with a few missiles. There is no point in having a G-limiter in the real Flanker when it does not do its job.

 

I would really appreciate if the G-limiter in the Su-33 would be fixed.

Link to comment
Share on other sites

Well, I have the same issue, but who cares.

Just stop flying on 20 y.o module and pay for f-16.

I didn't notice your irony marks or are you serious about proposing F-16 as an alternative to flying the Su-33?

🖥️ Win10 i7-10700KF 32GB RTX3060   🥽 Rift S   🕹️ T16000M HOTAS   ✈️ FC3, F-14A/B, F-15E   ⚙️ CA   🚢 SC   🌐 NTTR, PG, Syria

Link to comment
Share on other sites

BlackPixel, you are aware the limiter is calibrated for four missiles and 50% fuel right? And that holding full stick overrides the G limit/alpha limiter? Don’t think I had seen those mentioned before on this thread

Black Shark Den Squadron Member: We are open to new recruits, click here to check us out or apply to join! https://blacksharkden.com

E3FFFC01-584A-411C-8AFB-B02A23157EB6.jpeg

Link to comment
Share on other sites

Holding full stick in DCS is activated by pushing the g limiter overwrite button, so without pushing the button the limiter should work.

 

In the Su-27 the limiter always does its job, only in the Su-33 it fails when flying fast.

 

Is the calibration that you mentioned for the Flankers in the game or from the real ones?

 

You can snap the wings in the DCS Su-33 with 2xER, 2xET and 2 ECM pods and 25% fuel.

Link to comment
Share on other sites

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...