Understanding the Flanker

[Mrtanqueray]

I know the Su-27 has a lot to offer, and I have been trying to unlock that "sweet spot" where I am enjoying the Flankers special characteristics to my advantage in a dogfight without getting too bogged down by its dangerous quirks.

 

A couple questions for anyone who has found said sweet spot and can give some insight

 

Problem 1

The flanker is defined by, and vaunted for it's high AoA capability and instantaneous turn rate (NOT talking about "that" switch), but in my experience it is almost never worth using because:

 

a. the aircraft loses so much speed if you make use of the outrageous turn rate that it puts you at a big disadvantage

b. the nose bogs down after such a maneuver ruining any gunnery for the following moments and putting you off pace in your pursuit

 

My question, when do you experienced Flanker pilots actually go ahead and use the flankers instantaneous high AoA capability? Give me a common scenario where you really pull back on the stick.

 

Problem 2 (assume sea level, opponent is f15, both aircraft 30% fuel, 2 dogfight missiles, clean otherwise)

Whenever the fight goes vertical I feel like I'm playing with fire...

The nasty stall characteristics and lack of power of the Su27 means that if I decide to follow my target up I need to break off the chase and put my nose down around 450kph so I don't stall out. Not only is this almost always before my target has to drop his nose, but it happens extremely quickly (10,000 feet? if that?). Essentially forcing me to expose my tail as I drop off prematurely if I haven't nailed him with my cannon (which I usually do, but still).

 

My question. Given the above assumptions what do you all do when the target goes vertical? Set yourself up to catch him on the way down? gain altitude on a different heading and at a less aggressive climb rate?

 

Really hoping I can enjoy everything this plane has to offer, thanks! :pilotfly:

[rrohde]

Good observations (which I share). Curious what others have to say about that as well.

[Falcon_S]

Totaly agree with OP. I experienced same problems.

 

I think main problem is trim mechanism in DCS Su27 wich give us very bad results in listed situations and main reason for extreme losing speed (to fast) at high AoA.

 

My conclusion: We are bad trimed always in our flights because trim system is very bad in Su27.

 

I can`t believe that trim is in RL Su27 very bad as in DCS. I saw many cockpit videos about Su27 and never see pilot that triming plane constantly. In DCS after every move we lose a bit speed and must trim, again and again... If not change trim we have results from OP observations.

[Mrtanqueray]

Glad to see it's not only me.

 

I typically trim to about 600kph before the dog-fight and leave the trimmer as is so I will have a more compliant nose when I go guns (usually 500-600kph range). You think the loss of energy in vertical is coming from trim? That's interesting but I can't see why, can you explain more?

 

Also all you Flanker pros out there, help us out. Some answers to the original post would help us all.

[GGTharos]

Problem 1

The flanker is defined by, and vaunted for it's high AoA capability and instantaneous turn rate (NOT talking about "that" switch), but in my experience it is almost never worth using because:

 

My question, when do you experienced Flanker pilots actually go ahead and use the flankers instantaneous high AoA capability? Give me a common scenario where you really pull back on the stick.

 

It depends.

 

You have the opportunity to make an un-matched turn in the merge, which gives you the advantage right away. Do you need to pull until you're out of energy? How much is enough?

What's your bandit doing? Are you slow, he's fast, and you're still blowing all your energy? Why not a sustained turn instead? Do you really have to stick him in your HuD right away and try to gun him? Why?

 

In other words: Learn BFM, and the first rule of BFM is that the answer to your question is 'it depends' ... on a lot of things.

 

Problem 2 (assume sea level, opponent is f15, both aircraft 30% fuel, 2 dogfight missiles, clean otherwise)

 

My question. Given the above assumptions what do you all do when the target goes vertical? Set yourself up to catch him on the way down? gain altitude on a different heading and at a less aggressive climb rate?

 

So, you know ... it depends.

 

If your opponent is at 800kph, and you're at 450 ... why are you even trying to follow him up? Maybe you have a good reason - your dogfight missile might be able to catch up with him so it's worth a shot. Maybe you don't have a good reason, but you really like sticking him in your HuD (ie. you are a hud-fighter).

There are plenty of other variations.

 

And here's the real rub: All of this has absolutely nothing to do with what aircraft you're flying, your questions are basic BFM questions with the guise of applying to a specific aircraft.

[escaner]

My question, when do you experienced Flanker pilots actually go ahead and use the flankers instantaneous high AoA capability? Give me a common scenario where you really pull back on the stick.

 

Hi AOA is nice to have available when you are stuck in pure of lag pursuit to pull your nose ahead of the target for a shot. Usually it also allows you to fly very slow, which is also useful in a scissors or rolling scissors manoeuvre.

OTOH, high AOA = lots of drag, so you can lose a lot of energy when played wrong.

 

My question. Given the above assumptions what do you all do when the target goes vertical? Set yourself up to catch him on the way down? gain altitude on a different heading and at a less aggressive climb rate?

 

As GGTharos said, this is BFM.

 

When your target goes vertical, of course you should follow him. If you can't it probably is because he has more energy than you, so you better end the fight quick on the way up or he will be in your 6 on the way down.

 

If you don't (or cannot) follow, you are giving away to him all that turning room. He will be able to come down on you easily.

 

When you don't have the energy to follow him, you can unload your aircraft (level wings, 1G), accelerate and follow him when you can. But the longer you wait, the more turning room you are giving to him.

 

You say that you are pretty low, so you could also accelerate going down and seek for cover in the terrain to deny him a shot.

 

Remember that the Su-27 has a big advantage in close combat: use your helmet/AA-11 off boresight capability.

[Mrtanqueray]

Thanks for the feedback guys!

 

Escaner's advice about gaining velocity for a second before going vertical is something I'm going to pay attention to next time (will try today). In the meantime GGtharos I want to drill down a little deeper and try and get more specific knowledge out of you about when you use high AoA menuevers in the 27, read below.

 

Do you really have to stick him in your HuD right away and try to gun him? Why? -GGTharos

 

Quite the opposite. I have found I do not really ever find it worth it to use the 27's high aoa turning capability because of the consequences (loss of energy\altitude, sluggish nose) are too great. Which, to answer your question more specifically means rather than stick the enmy in my hud I tend to play the Su-27 as a very lag pursuit kind of jet because I fall out of the sky otherwise.

 

My question to you GGTharos, with all due respect of course and if this is actually possible, is how can I use my high AoA/instant turn, in whole or in part in a way that does not rely on making an instant kill and will put me in a good position should the dogfight continue? EG: sustainable use of super maneuverability.

 

Can't wait to hear more!

[Ironhand]

...

Problem 1

The flanker is defined by, and vaunted for it's high AoA capability and instantaneous turn rate (NOT talking about "that" switch), but in my experience it is almost never worth using because:

 

a. the aircraft loses so much speed if you make use of the outrageous turn rate that it puts you at a big disadvantage

b. the nose bogs down after such a maneuver ruining any gunnery for the following moments and putting you off pace in your pursuit

 

My question, when do you experienced Flanker pilots actually go ahead and use the flankers instantaneous high AoA capability? Give me a common scenario where you really pull back on the stick.

Boy. We all show up at once, don't we? :) And I am far from an expert, when it comes to dogfighting. But the thing about that high instantaneous turn rate is that it's, well..., gone in an instant. You can't hold onto it, and once you've used it, you have to work to get it back. It's kind of like a paycheck. Cash it, spend it, and you're done until you earn more. So use it only when you know it'll pay big dividends. Otherwise, try to fly at a high enough airspeed, if your opponent will let you, that your maximum instantaneous turn rate is always available for when the right moment comes.

 

 

Problem 2 (assume sea level, opponent is f15, both aircraft 30% fuel, 2 dogfight missiles, clean otherwise)

Whenever the fight goes vertical I feel like I'm playing with fire...

....

I think your underlying premise is that, with each aircraft configured similarly and carrying 30% fuel, they are more or less equal in weight. They aren't. That setup leaves the Flanker weighing roughly 1/2 again as much as the the Eagle. So, in that scenario, the Eagle is much lighter to begin with. So, perhaps, what's happening isn't all that exceptional.

[Nedum]

It depends.

 

You have the opportunity to make an un-matched turn in the merge, which gives you the advantage right away. Do you need to pull until you're out of energy? How much is enough?

What's your bandit doing? Are you slow, he's fast, and you're still blowing all your energy? Why not a sustained turn instead? Do you really have to stick him in your HuD right away and try to gun him? Why?

 

In other words: Learn BFM, and the first rule of BFM is that the answer to your question is 'it depends' ... on a lot of things.

 

 

 

So, you know ... it depends.

 

If your opponent is at 800kph, and you're at 450 ... why are you even trying to follow him up? Maybe you have a good reason - your dogfight missile might be able to catch up with him so it's worth a shot. Maybe you don't have a good reason, but you really like sticking him in your HuD (ie. you are a hud-fighter).

There are plenty of other variations.

 

And here's the real rub: All of this has absolutely nothing to do with what aircraft you're flying, your questions are basic BFM questions with the guise of applying to a specific aircraft.

 

He never wrote this things down your are talking about, so where do you get this stuff in your answer?

Where do you get this 800 kph versus 450 kph thingie?

Sometimes you talk to the people like they are all toddles... that's not fair.... not gentleman like!

Do you really think all that people fly the first time?

There is NO other DCS AC what people talking that much about a strange FM like the DCS Su27, and that's not because they are all "noobs". The DCS Su27 FM behaves strange, even for or just because this AC is one of the most agil ACs in DCS.

If "agil is meaning "should stall all the time", than I think the FM of the DCS Su27 is perfect, but otherwise there is work to do!

 

If you want us to proof wrong, show us please your skill track, so we can learn from you.

[GGTharos]

Quite the opposite. I have found I do not really ever find it worth it to use the 27's high aoa turning capability because of the consequences (loss of energy\altitude, sluggish nose) are too great. Which, to answer your question more specifically means rather than stick the enmy in my hud I tend to play the Su-27 as a very lag pursuit kind of jet because I fall out of the sky otherwise.

 

Then I'd say you didn't have enough energy to do what you wanted to do to begin with, but that's a very simplistic answer. Your high turn rate is used to gain angles. You can then continue to increase this initial advantage. But note there's a difference between a screeching break-turn right onto high six and a max performance turn to gain 30 degrees of angles. That difference is counted in lost airspeed. :)

 

My question to you GGTharos, with all due respect of course and if this is actually possible, is how can I use my high AoA/instant turn, in whole or in part in a way that does not rely on making an instant kill and will put me in a good position should the dogfight continue? EG: sustainable use of super maneuverability.

 

You have no super maneuverability. Forget that idea right now, it's not available to you. The flanker flies like any other aircraft: It gets sluggish t slow speeds, and loses speed in high AoA turns. It isn't magical and doesn't have thrust vectoring.

 

The flanker can't recover it's corner quite as fast as an eagle if you get it slow (but again ... it depends). On the other hand if you get the eagle slow too, the flanker will generally out-perform it if they're at the same altitude.

 

This is all about knowing the best maneuvering speeds for your plane, and not falling out of them unless you have a good reason to. So again, use a hard turn to gain some angles but don't do it in such a way that you're left wallowing around. If you find yourself stuck in lag now it's because you used up too much of that energy and/or you're not using your offensive or neutral position to build it back up.

 

All that is generalities because frankly, all this depends on the specific of your fight. There are far better resources than me on the subject, but the most important thing is that you need to put real brains into it. Yep, you have to crunch numbers, look at graphs, crunch more numbers ... that is the real answer.

[21stCenturyPilot]

In ACM energy management is very important. Speed is life. Finding yourself low and slow is bad, pilots try to avoid this.

Be gentle with the stick and don't use too much alpha (AOA) or bleed off too much speed, afterburner helps and a dogfight will use a lot of fuel. You can use high alpha to get a kill but be aware it will bleed off a lot of speed and with full burner it will take time to recover the energy you lose and if you find yourself low and slow you will be an easy target.

 

The Su-27 seems a bit weird I think, the Mig-29 seems to fly a lot nicer and smoother.

[Trailer]

I've noticed the endless trimming as well, even just flying straight and level. I just turn on altitude hold when I'm between waypoints and look around.

 

The Su-27 is practically steam-powered in comparison to jets like the Su-30 or 35. I think we should manage our expectations.

 

I'd love to see a flyable Su-30 with that glass cockpit and thrust vectoring.

[Exorcet]

You seem to be focused on gunnery. I'd only use the gun as a last resort. I also fly the F-15 mostly, but I'll still add some things in.

 

a. the aircraft loses so much speed if you make use of the outrageous turn rate that it puts you at a big disadvantage

b. the nose bogs down after such a maneuver ruining any gunnery for the following moments and putting you off pace in your pursuit

 

My question, when do you experienced Flanker pilots actually go ahead and use the flankers instantaneous high AoA capability? Give me a common scenario where you really pull back on the stick.

 

There are actually times when you want to lose speed. Again, my experience in the F-15 is much more, but this should apply to anything. There are times when I intentionally enter turns above corner speed and then pull my speed down with max instantaneous turns. This can give me a better turn rate overall, or allow me to keep my energy before I enter the turn.

 

Another use for this would be forcing an overshoot.

 

 

Here I am being terrible at Lock On (and recording because the sound is totally messed up) 5 years ago, but I think the video can show the basic point I'm trying to make. At 0:45 and 2:45 I get the AI to overshoot by using my instantaneous turning to slow down. They could have been better executed, but luckily the AI is dumb. With better timing and situational awareness than I had you could use a maneuver like that (basically a form of scissors) to force an overshoot. In a guns fight it would be a problem that your opponent would now probably outspeed you (unless he makes the mistake of slowing) but with missiles this isn't necessarily a bad thing.

 

 

Speaking of missiles, high AoA ability combined with the Su-27's helmet sight is a good thing.

 

Problem 2

(assume sea level, opponent is f15, both aircraft 30% fuel, 2 dogfight missiles, clean otherwise)

Whenever the fight goes vertical I feel like I'm playing with fire...

The nasty stall characteristics and lack of power of the Su27 means that if I decide to follow my target up I need to break off the chase and put my nose down around 450kph so I don't stall out. Not only is this almost always before my target has to drop his nose, but it happens extremely quickly (10,000 feet? if that?). Essentially forcing me to expose my tail as I drop off prematurely if I haven't nailed him with my cannon (which I usually do, but still).

 

My question. Given the above assumptions what do you all do when the target goes vertical? Set yourself up to catch him on the way down? gain altitude on a different heading and at a less aggressive climb rate?

 

Really hoping I can enjoy everything this plane has to offer, thanks! :pilotfly:

The Eagle generally climbs better. In this case my goal would ignore the gun completely. I'd let the F-15 climb while I just maintain my speed and get him with HMS if possible.

 

If this is vs a human opponent, don't forget that you can try flying in an unexpected direction and hide. Doesn't work against the AI though.

[Gargoil]

Whats the optimal sustainable turning speed for Su-27? ~650 km/h?

And what's the best for F-15C in knots/h?

[GGTharos]

At what altitude? At what gross weight? For what purpose?

[esb77]

Whats the optimal sustainable turning speed for Su-27? ~650 km/h?

And what's the best for F-15C in knots/h?

 

There are charts for both, and it depends on load and altitude a bit.

http://forums.eagle.ru/showthread.php?t=133922&highlight=Su+27+turn+chart&page=2

 

 

That's a sample.

 

For sure numbers you either need to know what algorithms the sim uses to calculate for specific conditions, or you need to run a flight test program to figure out exact values. It's a lot of test flights and demands very precise piloting, but that will get you the best numbers for what's actually in the sim.

 

For ballpark figures with a moderately loaded plane the charts around the forums are probably o.k.

Edited February 28, 2015 by esb77

[Gargoil]

Thanks :thumbup:

[Mrtanqueray]

Thanks for your input (was meaning to reply but work the weekend)

 

I think the bottom line is when I treat the flanker like a normal plane I do alright. On the other hand it's got so many quirks (trimming, stall tendencies, and TWR) that I find it hard to justify flying it unless I'm really looking to challenge myself.

 

I'm sure there hasn't been enough tech info released to the public for ED to make us a Su30/35 but I think, at this point, just for the sake of being competitive that's at top of my wishlist.

[amazingme]

@ Mrtanqueray

After flying the Flanker for a while I find it very enjoyable, especially in dogfights (guns only). I usually fly it with 40% (unlimited) fuel and I use the "S" key in almost any situation.. even at very slow speed ~250Km/h it CAN outmanoeuvre any jets out there. I know that the implementation of the S key (FBW, AoA off), without the damage model being updated, allows you to pull some immense Gs without the plane breaking apart or the pilot dying.. but still.. it's very stable with direct control as long as you keep you stick pulled (@ slow speed).

I can easily win any 'guns only' dogfights by turning and having direct control of the bird.

So, my personal advice (as GGTharos brilliantly suggested) is to first learn BFM and AFM and then fly a few hundreds hours with the Flanker to get an idea of what this magnificent aircraft can really do.

I also prefer to drop all weapons and get into a guns dogfight as I can easily dodge any missiles (don't ask how;) ) that you can throw at me WVR. We can meat online if you join AMAZING's server..my (fun) server. I got TS if you need further in-game details..

HF!

Edited March 3, 2015 by amazingme

[ALI-G]

Step 1 I'd recommend practising figuring out the slowest speed you can take the flanker vertical I don't know what it is off hand probably around 300kts. figuring out the slowest speed to go vertical is key in bfm rarely do you want to get below this speed. If you do it should be to get the nose on for a shot otherwise you'll need to unload <1 G to get this speed back otherwise you'll be sitting waiting for the eagle or big mouth viper to climb above you and club you like a baby seal. Just to touch on the one problem of the eagle being above you remember if you both go vertical the objective isn't to out climb each other it's a one circle fight or nose to nose fight so you want to max perform to get your nose on him first this. The bandit will have to react and you may get a brief archer lar or try a snap.

[Stuge]

Here's my thoughts:

 

High instant turn rate is useful in many cases, even if it costs you energy:

-one circle fight(tight radius)

-rolling scissors(limiter off for maximum tightness and braking!!)

-pulling down from the top of a loop(limiter off again, lets you swivel the nose down faster)

-any moment you see that "instant kill" possible, be it with a missile shot or gun shot. With limiter off you can turn your nose over 90 degrees from an airspeed of 400 kmh. And if you're light, recovery can be fairly quick even from a full cobra maneuver.