Su-27 problem with rudder.

Hello. Recently I noticed that there is a problem with the rudder in Su-27. Flying at the speed of, for example, 700 km / h, kicking the rudder (even not too strong) causes the two rudders to be broken off. Earlier this situation did not occur. In general, I've found that recently the Su-27 fighting assets have deteriorated significantly. Is there any explanation for the changes introduced in the Su-27 flight model. Currently, it is the slowest and worst turning fighter.

Because every NATO plane has to be better.

This is the most probable theory that I think about. Especially at the time of the F-18 release.

This is the most probable theory that I think about. Especially at the time of the F-18 release.

Everything about russian fighters sucks in this simulator.

It is disturbing and annoying, because it soon turns out that on the red side no one will want to fly, because there will be nothing valuable there.

Sounds like the FBW protection for this was removed or something else changed - the rudders breaking under stress is realistic, but there should be some protection against it. Hopefully Yo-Yo can comment.

But importantly, because I don't have time to try and reproduce this right now:

What are the detailed conditions for this? 700kph is not enough information. What altitude? Mach number? Are you putting g's on the airframe? Are you kicking rudders back and forth? (Why is there rudder input at 700kph?)

The Su-27 is an excellent turning machine, tested multiple times. It's ability to turn is superior. You just have to respect the aircraft's limitations - meaning, per the actual, real, used by pilots flanker manual, you'll have better sustained turning than an F-15C at <0.6M when loaded with 2xR-27R, 2x-73, 30% fuel and the eagle is at 50% fuel, clean, and 4 missiles.

You always have better ITR in theory, but in practice ITR runs up to AoA and G limits, so you have to think about how you want to use it.

Hello. Recently I noticed that there is a problem with the rudder in Su-27. Flying at the speed of, for example, 700 km / h, kicking the rudder (even not too strong) causes the two rudders to be broken off. Earlier this situation did not occur. In general, I've found that recently the Su-27 fighting assets have deteriorated significantly. Is there any explanation for the changes introduced in the Su-27 flight model. Currently, it is the slowest and worst turning fighter.

I found this just after the start, at an altitude of 500-800 m, flying straight. Kicking to the right and left and rudders canceled. I note that it was not before (several patches backwards). And not only I noticed it.

Hello. Recently I noticed that there is a problem with the rudder in Su-27. Flying at the speed of, for example, 700 km / h, kicking the rudder (even not too strong) causes the two rudders to be broken off. Earlier this situation did not occur. In general, I've found that recently the Su-27 fighting assets have deteriorated significantly. Is there any explanation for the changes introduced in the Su-27 flight model. Currently, it is the slowest and worst turning fighter.

I wish people would have all the information before they start to freaking out about nothing.

You say you where at 700kph and lost your rudders.

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Here I am at well over 700kph with full rudder deflection and no problem, so before we get the pitch fork on how "evil" ED is and how poor the red aircraft, yata yata, I think we need more info. What altitude, speed in mach, was this online, single player, what map, what version ( the hole thing like 2.5.2.17559.377, which the current beta version) etc. The more information you provide the easier would be for people to duplicate and hopefully find the cause (if any) of the problem.

Yes, previously building up enough stress required a bunch of left-right rudder shifts. Not sure why it would change now.

I found this just after the start, at an altitude of 500-800 m, flying straight. Kicking to the right and left and rudders canceled. I note that it was not before (several patches backwards). And not only I noticed it.

so before we get the pitch fork on how "evil" ED is and how poor the red aircraft, yata yata.

Why are you shifting the problem on ED? Its a fact that red aircrafts suck in order to satisfy the blue aircraft pilots. It is not what ED wants.

I am not shifting the problem to nobody, I don't see any problems except people freaking about nothing.

Hello. Recently I noticed that there is a problem with the rudder in Su-27. Flying at the speed of, for example, 700 km / h, kicking the rudder (even not too strong) causes the two rudders to be broken off. Earlier this situation did not occur. In general, I've found that recently the Su-27 fighting assets have deteriorated significantly. Is there any explanation for the changes introduced in the Su-27 flight model. Currently, it is the slowest and worst turning fighter.

As per page 117, para. 3 of the DCS Su-27 flight manual, rudder travel should be limited to 50% above speeds of 600 Km/h.

This is slightly different in the real Su-27 in that rudder travel is limited at speeds over 600 km/h to no more than double the turn & slip ball diameter. Rudder movement is limited to 1/3 of total travel at a force of 17 kg on the relevant pedal.

To be fair the above refers to the Su-27SK not the -27S as we have, however I can't find anything to suggest that the rudder channel of the ACS differs in any way for the two variants.

As to the Su-27 being the slowest turning, I'd refer you to GG's comments above. It's entirely dependant on configuration but to say that it's the worst performing is factually false. IIRC under optimum conditions it is in fact the best performing, with the possible exception of the MiG-29S.

It is a fact that you are wrong.

Conspiracy theories like this aren't particularly welcome, and provably false.

Why are you shifting the problem on ED? Its a fact that red aircrafts suck in order to satisfy the blue aircraft pilots. It is not what ED wants.

It'll happen, if you're engaging the "Y" key while ruddering. Otherwise seems OK in very limited testing.

1 trial. Gulf map. On runway, rudders deflect fully. At 1000m and 700 IAS, rudders deflection is more limited. At same altitude and 1000 IAS, rudder motion even more limited and no issues. Engaged "Y" key at that point. Still at last altitude and airspeed, deflected rudders. Rudders deflected further than without "Y" key and immediately lost both vertical stabilizers.

Ok. Now I understand that Su-27 is worst modern aircraft @DCS World. True? It is slowest and very heavy. Is @DCS any other modern aircraft that performes worst then Su-27?

How is the SU-27 the worst aircraft in DCS? I need to quit coming to this forums.

How is the SU-27 the worst aircraft in DCS? I need to quit coming to this forums.

I mean dogfight. If your speed is lower then your foe, he is able to disengage, you are not. So if you at df at visual range with Mirage or F-15C you play on them rules. Tell me witch modern russian aircraft at DCS could engage and disengage at will?

Best,

=OPS= boski_qrdl_logos (SL)

Ok. Now I understand that Su-27 is worst modern aircraft @DCS World. True? It is slowest and very heavy. Is @DCS any other modern aircraft that performes worst then Su-27?

Serious question: are you trolling?

Let me assume for a moment that you're not. The Su-27 is not the slowest aircraft in DCS, it's actually the fastest (playable) at the moment, capable of Mach 2.53 at 12,500m altitude, which is significantly faster than it should be. It can be relatively heavy, depending on configuration, but WVR performance is heavily dependant on configuration. At under 35% fuel load, with 4 missiles loaded, the Su-27 will out-turn everything except the MiG-29. Added to this it has a very high off-boresight capability with the R-73 which is further boosted by the helmet mounted sight.

On the other hand if you have >90% fuel and a full missile load then turning performance will be significantly lower. The same applies though to any other aircraft. For example, an F-15C that has a full missile load and 3 x fuel tanks loaded will also have a significantly lower turning ability than at ideal conditions.

To address your later question, speed is not the characteristic that will decide who will win a WVR fight. Turning ability and the ability to successfully bring weapons within launch parameters are much more important in WVR combat. To use your example, if an enemy turns away to extend during a dogfight then they make themselves an excellent target for a follow-on R-27ET missile shot. If they maneuver to avoid the missile then they're back in WVR combat and have not escaped.

I can't think of any aircraft that actually exists that can enter and exit WVR combat at will with no consideration for the enemy aircraft involved in the fight.

I am not trolling, but I play Su-27 since Flanker 1.0... and feel that from about year ago Su-27 starts to perform worse, and worse comparing to F-15C or Mirage. We, I mena =OPS= plays one mision "Polonez" since many years exacly at the same area. I know, it sounds boring :-) but we can notice evry change to FM, DM etc. To be honest F-15C is slighty worse than used to be few years ago, but Su-27 is much worse... Now if you engaged at close dog with Mirage or F-15 you have to have luck to make advantage. But if you engaged at gunzo you have no chance to disengage. Downgarding Su-27 is kind of long proces and It is my strong belief.

Best,

qrdl

Su-27 has been made more realistic. It turns out it was never capable of magical dogfighting, but it definitely has a huge edge in certain types of dogfighting if you respect the necessary parameters for this. In fact, it can jam/fight most other aircraft all day long under the right circumstances.

If you believe it doesn't fly well, I suggest complaining to Sukhoi.

As for 'compared to other aircraft', irrelevant: It should only be compared to itself.

It is true that some DM effects are missing, especially from F-15 and F-5 ... but the effect of this is marginal, unlike say, abuse of 'S' key when there was no DM on the Su-27.

When overload DM is applied to the F-15 in particular, the fight will change a bit but not that much - those who suffer will be the ones who haul 2-3 FULL bags of fuel into a fight. There you could have an eagle break up from over-g, but once the bags are off, it won't be any different.

You'll break the rudders if you actively move them on speed above 600 kph. That has long been known. IRL su-27 has a spring limiter and it's not so easy to owerpower it and break the rudders. And of course it doesn't mean that if you do that your stabilizers will explode. But we have what we have. You can shake F-15 with rudders on 1.5mach doing barrel rolls with 20g. yeah boooy

The most annoying thing to me about Su-27 is trimming..

Do you guys trim a lot with Su-27?

Maybe I am doing something wrong.... but yeah F15C is much more enjoyable to fly.

The most annoying thing to me about Su-27 is trimming..

 

Do you guys trim a lot with Su-27?

 

Maybe I am doing something wrong.... but yeah F15C is much more enjoyable to fly.

It becomes much easier if you bind trimmers to the hat switch.

Flight control system on su-27 is not programmed for straight flight on purpose.

It's a bit old school vision I think.

The most annoying thing to me about Su-27 is trimming..

 

Do you guys trim a lot with Su-27?

 

Maybe I am doing something wrong.... but yeah F15C is much more enjoyable to fly.

Trim a lot? Yes and no. In the Su-27, with your gear up, the FBW system is designed to pitch your nose up as your speed increases and drop your nose as your speed decreases. If nothing else, this keeps you constantly aware of changes in your airspeed. As Velik noted, tying the trim to a hat switch makes trimming easier, though I never had much of a problem even before I did that. It just simplifies the process.

One thing to be aware of is that, once you have settled in, more-or-less, on an airspeed, the aircraft will ajust itself as long as the trim is close. During the process, you will slowly rise and fall several hundred meters. Your airspeed will slowly decrease as you rise until you start to descend. Then it will slowly increase but not quite to the airspeed at which the process started. The amplitude of these oscillations will slowly decrease until you are in level flight at a constant airspeed. But, like I said, it takes awhile and, if you have someone flying your wing, it'll drive him crazy.

I actually prefer the Su-27 to the F-15, partly because of this behavior. It's just more fun to fly. But, then again, a number of people think I'm a bit odd...