Su-27. Extreme G-loads... G=?

[Bushmanni]

Bending usually doesn't make any sound and even if some sound is created it's not loud or something you hear over wind and engine noise in a fighter. Usually when something breaks it's just a sudden bang.

 

[ame]

[/ame]

[Jinks]

Bending usually doesn't make any sound and even if some sound is created it's not loud or something you hear over wind and engine noise in a fighter. Usually when something breaks it's just a sudden bang.

 

 

That's a cool video. I'd be curious to know if they had a microphone anywhere near the wing itself while loading it.

 

Even if an audio cue doesn't makes sense, it's quite obvious that the the stress was visible. The flanker wings aren't nearly as long but it's hard to imagine there wouldn't be at least some flexing before they just snapped off.

 

And again - the point for many of us is not whether or not this should be modeled. It's how it's modeled now. The point isn't being made to use the over-ride and pull a 20G maneuver. That's quite obviously not realistic.

 

Is it really accurate that the computer (still engaged) cannot handle rolling and leading to the situation where the wings snap off very suddenly. If not rolling the issue isn't there. Yes that can be learned but is it accurate?

Edited April 10, 2016 by Jinks

[GGTharos]

There are two concurrent threads regarding the new damage model for flanker filling up now 13 pages and filled with a lot of discussion that's going all over the place. Reasonable questions are being lost by extraneous points in all directions. Effectively devolving the conversation to a F15 vs Su27 fanboy war. Using "real world" examples of why an F15 would never have it's wings come off then failing to provide examples of a Su-27 flying apart with a fully functional computer makes no sense. Complaining that the F15 is easy mode / "arcarde" is equally as pointless.

 

Quite right - one of the problems is that we don't have any data for the Su-27 - YoYo does, and his sources are very good. But there are also implementation choices as well, which may have been made without us knowing the reason for them.

 

No. You do not need to over-ride the ACS or AoA to have the wings rip off. This has been explained and is easily reproducable. Go over 800km/h roll inverted while pulling.

 

I would argue that you should not pull and roll at the same time. This is basic flight technique - manipulate one axis at a time. Blending is relatively advanced stuff.

Lateral g limits are typically even lower than longitudinal (but would they actually cause structural failure or would they just over-g pylons etc?) - however, there arises another question: What's the GW when you do this?

 

Wings ripping of without warning and without over-riding the computer is a valid concern. There have been many posts implying that this is hard to do. It is not difficult at all as pointed out and easily reproducible.

 

When aircraft break up, there's pretty much no warning. Regarding the computer - maybe at least the over-g warning should be better programmed. Having said that, I don't have any documentation on how it is actually programmed :(

Regarding the FCS: It's not necessarily aware of what's been strapped onto the plane. It might seem very logical and easy for us to say 'but it should know! You can feed all this data here and here and there!' but it doesn't mean it's that way in RL, for any number of reasons.

 

The other valid point made by a few people is that there is zero warning. It just happens instantly - which is likely not the best behavior.

 

It is the correct behavior.

 

If the simulation is monitoring flight data for a certain condition to be met... Perhaps there is a way to let the dumb pilots - sitting in his chair at 1g - know he's about to rip the wings off when approaching that condition. Or perhaps it makes sense to allow for an instant of being over that condition, some type of audio cue (creaking), or anything that helps reduce the confusion.

 

I don't really agree. This is a matter of planning and being aware of your aircraft. If it has no mechanism to warn you, one shouldn't be added. This is what makes the difference between generations of aircraft as well.

It just means you have to be that much better at planning your flight and flying your aircraft correctly.

 

With THAT said, perhaps ED could provide some guidelines and graphs to help you plan your flight and to be aware of your aircraft's g capability :)

[IASGATG]

The P-51, FW-190, Me-109, UH-1, MI-8, Ka-50 (To a large extent), A-10 all lose their wings through poor flying without any warning. This isn't something that is unique to the Su-27. As someone who started off in the Hog, you quickly get used to not pulling 6g's when your jet is fully loaded if you want to keep the wings attached. If you're in a Huey you don't start throwing negative g is you don't want to mast bump, etc. It's just one of those things you as a pilot have to get used to.

 

I'm surprised nobody has brought this up sooner.

[ФрогФут]

Regarding the FCS: It's not necessarily aware of what's been strapped onto the plane. It might seem very logical and easy for us to say 'but it should know! You can feed all this data here and here and there!' but it doesn't mean it's that way in RL, for any number of reasons.

Some Su-27 do have Limiting signals system, which knows about fuel load and payloads and sends the signals to the G/AoA limiter and will limit your actons accordingly. Some only have transonic drop programmed into limiter and they are working only for optimal GW - 21400 kg.

[GGTharos]

Frogfoot, by 'some' do you mean 'newer' like Su-27SM upgrade?

 

Another question for you: Is the basic empty flanker 16500kg or 17500kg? :)

[Jinks]

The issue for many of us has nothing to do with being able to learn the new behavior. It's whether or not it's completely accurate. As you've pointed out there are others with more complete data who may be paying attention and trying to interpret how to implement that data the best way possible. Discussion doesn't hurt. In my post I did shoot down a couple of comments - because they are easy to prove incorrect in the sim itself - and serve no constructive purpose. Many points/questions/opinions are also being shot down based on some seemingly esoteric understanding of "real world" behavior of very complicated and intricate issues.

 

I have a non-technical question to ask you. Have you flown the flanker with the new update and tried to reproduce the non override wing failure? Not the mach 1 post merge cobra which most people would agree needed to go away. The point for many of us was the wings ripping off unexpectedly while cranking/defending at medium ranges. Straight up it just feels very wrong. Not very scientific and maybe totally lost on you which is fine.

 

If it's to be left that way so be it. Enthusiasts will learn. However it's probably a good idea to make sure that is absolutely the intended behavior and is modeled correctly. Without resorting to a flanker / eagle flame war we can still call a spade a spade.

 

Under the current conditions you have a situation where one can fly it's wings off by going defensive and the other does not. Nothing to do with cobra button. What real world proof do we have that this is realistic? A bunch of textbook numbers being thrown around. An example of an eagle surviving sustained over g (it's better than it's textbook numbers) and zero example of a flanker flying it's wings off (so it obviously can't)... Using textbook numbers for one plane and not the other is just simply never going to make sense to many of us.

 

Regardless of what order the flight models are upgraded in - trying to make the sim balance them to be "fair" is the wrong approach. However a case can be made for balancing the logic used to come up with those upgrades. The end result most of us want is an accurate and fun simulation experience for everyone.

Edited April 10, 2016 by Jinks
clarity

[mvsgas]

Thanks for using my spanish translated manual mate. Really pleased.

Thank you

 

The P-51, FW-190, Me-109, UH-1, MI-8, Ka-50 (To a large extent), A-10 all lose their wings through poor flying without any warning. This isn't something that is unique to the Su-27.

Really good point, thanks.

[probad]

The end result most of us want is an accurate and fun simulation experience for everyone.

fun varies wildly based on the person, there are many people who only have fun if they are given a godplane to turkeyshoot everyone else with. as these people who consider "winning is fun" outnumber the people who find "flying is fun", making "fun" a criteria to build the game around represents a fundamental chance in the direction of dcs from a flying game into a yet another one of the social engineering games that are so ubiquitous these days.

 

zero example of a flanker flying it's wings off (so it obviously can't)

just because there are no published account of flanker wing failures that the failure point does not exist; real pilots do not fly like flaming cliffs pilots. they most certainly do not load the plane to 70 tons and then try to fly as fast as they can while throwing the stick around.

Edited April 10, 2016 by probad

[Jinks]

just because there are no published account of flanker wing failures that the failure point does not exist; real pilots do not like like flaming cliffs pilots. they most certainly do not load the plane to 70 tons and then try to fly as fast as they can while throwing the stick around.

 

You can rip the wings off with very little stick input very easily. Try it yourself perhaps. If your opinion is that's how it should behave then so be it. Saying that we're going mach and throwing the stick doesn't address anything of substance.

 

Arguing for or against anything based on lack of documented proof goes both ways, that was the point I was trying to make.

[Winston60]

Obfuscation:

intransitive verb

: to be evasive, unclear, or confusing

 

There are two concurrent threads regarding the new damage model for flanker filling up now 13 pages and filled with a lot of discussion that's going all over the place. Reasonable questions are being lost by extraneous points in all directions. Effectively devolving the conversation to a F15 vs Su27 fanboy war. Using "real world" examples of why an F15 would never have it's wings come off then failing to provide examples of a Su-27 flying apart with a fully functional computer makes no sense. Complaining that the F15 is easy mode / "arcarde" is equally as pointless.

 

That discussion has no bearing on whether or not this was implemented in the best way for the Su27. There should be an official thread for that somewhere else to be used as a cathartic. There is some bad information being argued and I'd like to point out a couple.

 

 

 

No. You do not need to over-ride the ACS or AoA to have the wings rip off. This has been explained and is easily reproducable. Go over 800km/h roll inverted while pulling.

 

 

 

It's already been established that you do not need to exceed 12g's to have the wings rip off. While a lot of the complaints about this update have been rather whiney - the true irony here is the many posts trying to have a constructive conversation on whether or not this has been implemented correctly or in the best way - not whether it should be there at all.

 

---

 

Many of us (flanker pilots) totally understand and agree that you shouldn't be able to manually over-ride the computer without penalty.

 

Wings ripping of without warning and without over-riding the computer is a valid concern. There have been many posts implying that this is hard to do. It is not difficult at all as pointed out and easily reproducible.

 

The question has been posed whether or not this was intended and if it is actually correct. To some degree it was answered.

 

 

 

If the first shot at the new model is an accurate representation of real limitations of the computer then so be it. There's nothing wrong with wanting to get that right.

 

The other valid point made by a few people is that there is zero warning. It just happens instantly - which is likely not the best behavior.

 

Telling someone real pilots don't pitch while rolling doesn't address that.

 

If the simulation is monitoring flight data for a certain condition to be met... Perhaps there is a way to let the dumb pilots - sitting in his chair at 1g - know he's about to rip the wings off when approaching that condition. Or perhaps it makes sense to allow for an instant of being over that condition, some type of audio cue (creaking), or anything that helps reduce the confusion.

 

Questioning how it works or making suggestions does not mean one disagrees with the existence of the new damage model.

+1 All good and valid points. If ED used your post only to investigate the proper implementation of this new feature, I'm sure they would tweak what we have now and make it right. :smilewink:

[Ironhand]

..one of the problems is that we don't have any data for the Su-27 - YoYo does, and his sources are very good.

Then, perhaps, the best way to handle this is to systematically document (with tracks, tacview, and writeups) what is being observed and ask Yo-Yo to check into them, rather than several different threads where, for the most part, it's a case of the blind leading the blind. As you noted, there is very little info available.

[GGTharos]

I have a non-technical question to ask you. Have you flown the flanker with the new update and tried to reproduce the non override wing failure? Not the mach 1 post merge cobra which most people would agree needed to go away. The point for many of us was the wings ripping off unexpectedly while cranking/defending at medium ranges. Straight up it just feels very wrong. Not very scientific and maybe totally lost on you which is fine.

 

What's not lost on me is that you're not reporting the GW and g-loading when this happens. As Frogfoot pointed out, your g-limit under certain GW's can be as low as 6g. If you're 'defending' with 9g you're already past the max safe g * 1.3.

Tacview can give you a history of your g in this case as well, so yu can check if you have weakened your airframe previously.

 

Without resorting to a flanker / eagle flame war we can still call a spade a spade.

 

Ok, and then you say ...

 

Under the current conditions you have a situation where one can fly it's wings off by going defensive and the other does not. Nothing to do with cobra button. What real world proof do we have that this is realistic? A bunch of textbook numbers being thrown around. An example of an eagle surviving sustained over g (it's better than it's textbook numbers) and zero example of a flanker flying it's wings off (so it obviously can't)... Using textbook numbers for one plane and not the other is just simply never going to make sense to many of us.

 

The eagle's BAL is 9g at all GWs up to 68000lbs. You're saying it doesn't make sense, but you're treating it as if it was the same airframe.

 

Regardless of what order the flight models are upgraded in - trying to make the sim balance them to be "fair" is the wrong approach. However a case can be made for balancing the logic used to come up with those upgrades. The end result most of us want is an accurate and fun simulation experience for everyone.

[probad]

Then, perhaps, the best way to handle this is to systematically document (with tracks, tacview, and writeups) what is being observed and ask Yo-Yo to check into them, rather than several different threads where, for the most part, it's a case of the blind leading the blind. As you noted, there is very little info available.

yoyo's got to have better things to do than sitting down and watching tracks of players being bad and hamfisting a 65t plane rated for 48t through random wild maneuvers.

 

i often watch the fpv of other pilots in tacview and it blows my mind what some of them consider maneuvering

yet the first thing they want to blame is the plane

Edited April 10, 2016 by probad

[mvsgas]

Jinks, Winston

Could you guys provide more details? what weapons, fuel, weather, etc. I would like to duplicate the conditions where it brakes without warning. I tried and flying within limits, I did not encounter the aircraft breaking without warning. I notice the blacking out, the stick shaker, the wing flexing telling me to watch my G limits. I think if we all work together, we could at least learn from each other and everyone could have a better experience.

[Esac_mirmidon]

We are doing one wrong thing every day in DCS and nobody complains about it but the day they fix it it could be a madness taking in count some reactions here.

 

Maximum Landing Gross Weight.

 

Everyone has made a full load take off and inmediatly landing with this big weight excess and the plane didnt broke apart and this is very wrong. Just an example of an operational limit that everybody is not considering at all.

 

The new G load limit feature is the same thing. But now it works. Thats the difference. When the plane starts to break at landing because excending maximum landing weight it´s gonna be another game changer.

 

The Operational Limits are in the first places of many Flight Manuals for a reason.

[Jinks]

Jinks, Winston

Could you guys provide more details? what weapons, fuel, weather, etc. I would like to duplicate the conditions where it brakes without warning. I tried and flying within limits, I did not encounter the aircraft breaking without warning. I notice the blacking out, the stick shaker, the wing flexing telling me to watch my G limits. I think if we all work together, we could at least learn from each other and everyone could have a better experience.

 

Heading out at the moment but will post later. From memory just take a full plane get up to about 5000 meters @ 800+IAS might be easier to reproduce @ 900. fly level at that speed. Roll inverted and pull as if you were defending. You won't need to pull much if you get it rolling fast. The wings will snap instantly when you hit the right input.

 

Again, it's not that hard to learn to avoid it ... that's not why I'm abdicating for more examination. It just seems like it's super easy when rolling - like a bad calculation or something.

 

Regarding other comments... I think I've made myself as clear as I can and there's no point discussing with anyone who's not interested in understanding the issue. Or hasn't even tried it themselves. Hopefully all of our comments get looked at and taken on merit by the right people.

[probad]

full plane is 70tons, and documentation says that's not a weight you want to be throwing around at.

 

i wonder where the problem lies!

Edited April 10, 2016 by probad

[Esac_mirmidon]

What is Full Plane?

 

100% internal fuel plus 10 missiles?

 

How many G you are pulling while rolling inverted?

[Svend_Dellepude]

Too much seems like.

[Ironhand]

yoyo's got to have better things to do than sitting down and watching tracks of players being bad and hamfisting a 65t plane rated for 48t through random wild maneuvers.

 

i often watch the fpv of other pilots in tacview and it blows my mind what some of them consider maneuvering

yet the first thing they want to blame is the plane

 

I understand what you're saying. I am often sent tracks to view and, almost always, the real problem is that the individual is throwing the stick around. I'm thinking more in terms of a few folks, with specific fuel and weapon loads set to specific gross weights, flying at specific airspeeds., etc, etc. That's why I said systematically document.

[Seaeagle]

What is Full Plane?

 

100% internal fuel plus 10 missiles?

 

Well I guess that would be max take-off weight, which is some 30500 kg.

 

Empty weight ~ 16500 kg, max fuel 9400 kg and max ext. payload ~ 4450 kg.

 

So even 100% fuel plus 10 missiles won't take it to MTO.....need a bomb load for that :)

[mvsgas]

Well I guess that would be max take-off weight, which is some 30500 kg.

 

Empty weight ~ 16500 kg, max fuel 9400 kg and max ext. payload ~ 4450 kg.

 

So even 100% fuel plus 10 missiles won't take it to MTO.....need a bomb load for that :)

 

With that configuration and the information available to us it give it a max g of 5.6 below mach .85, 4.5g between .85 and 1.25 and 4.9 above mach 1.25.

 

Thanks guys. I think is very cool we have to consider load now (weapons and fuel) on previous aircraft (A-10, P-51, etc.) I could wing it :D, now for the 27 we have to pay attention it seems.

Edited April 10, 2016 by mvsgas

[Seaeagle]

With that configuration and the information available to us it give it a max g of 5.6 below mach .85, 4.5g between .85 and 1.25 and 4.9 above mach 1.25.

 

Hehe yeah, but then max TO is also a rather unlikely situation - even with a full load of fuel and max air-to-air configuration(6x R-27ER + 4x R-73), you would still have a couple of tons to spare(although the weight of launcher racks must be considered too) :) .

 

Thanks guys. I think is very cool we have to consider load now (weapons and fuel) on previous aircraft (A-10, P-51, etc.) I could wing it :D, now for the 27 we have to pay attention it seems.

 

Fuel in particular - the Su-27 can carry an insane amount of internal fuel.....I guess there is a reason why the fuel dump switch has a prominent place on the front instrument panel :)

[mvsgas]

Where can we find the ammunition weight? Gun ammo, missiles etc.

 

Edit

I found some in the manual.

I did not realize how heavy this missiles are.

R-27= 253kg

R-27ER= 350kg

R-27T= 254kg

R-27ET= 343kg

R-73= 105kg

 

I need to find the KMGU weight, rockets, rocket pods and gun ammo. I am not sure if we need to find the missiles rail weight and bomb/rocket pylons. Some aircraft include this on their empty weight.

Edited April 10, 2016 by mvsgas