Su-27 problem with rudder.

[WildBillKelsoe]

Why trim when you can use autopilot attitude hold and altitude hold when near level?

[probad]

why even fly at all if all you do is autopilot

[Ironhand]

Why trim when you can use autopilot attitude hold and altitude hold when near level?

:) In my case, it's personal preference. I almost never us the AP for anything. And, then, I don't have to remember to knock the AP off before I start maneuvering, if something unexpected happens.

 

But we're verring off the original topic.

[DarkFire]

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

 

Understood. My apologies since you were voicing a genuine concern. That being said, I think the Flanker has been brought in line with reality rather than having been significantly downgraded. The days of doing magical 50G turns using direct control mode are gone, and in my opinion rightfully so. As I said, performance is now heavily dependant on configuration, weapons loaded and fuel load. A lightly loaded Flanker performs astonishingly well at WVR whereas a Flanker carrying a maximum bomb load plus full fuel will turn like an airborne T-72 :)

 

Something that is tangentially related: I wish the fuel dump system worked in the Flanker. This would be really useful in order to dump some excess weight for combat and also for landing purposes.

 

Edited to add: fuel dump does in fact work perfectly, and has a nice graphic to boot! I hadn't noticed that FD was fixed. Nice work ED!

Edited May 29, 2018 by DarkFire

[DarkFire]

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, all the time. Any change in speed will require re-trimming the aircraft. In practice this means that any change in speed, any significant change in pitch without suitable throttle adjustment and any significant change in altitude will require re-trimming. As Velik suggested the best method of approach I've found is to bind the trim controls to a spare hat switch. This makes thumbing the trim switch almost an unconscious muscle memory action when you've been flying enough. If you watch cockpit video from real Su-27's the pilots are constantly thumbing the trim hat on the stick.

 

For better or worse Sukhoi designed the ACS on the Flanker so that it would mimic older direct control aircraft: nose up as airspeed increases and nose down as airspeed decreases. Given the superb nose authority and amazing high-AOA capability of the Flanker I feel that this was a really bizarre decision on the part of the design team but I suppose it makes transitioning from a trainer aircraft that much easier. For what its worth modern Flanker variants such as the Su-30MKi, Su-35 etc all have more modern fully fly-by-wire systems in which manual trimming is not usually necessary.

 

Finally a personal plea. If anyone from ED reads this, could we please, for the love of all that is holy, PLEASE make the trim reset work on the roll channel? Please? The near-inability to zero out roll trim by manual trim inputs is the single most infuriating thing about flying the DCS Su-27.

 

 

FINAL NOTE ON RUDDER BREAKAGES:

To the OP: I tested this at all sorts of altitudes up to 10,000m and all speeds up to Vmax (2,700 Km/h TAS). At any speed and at any altitude the AOA/G limiter will save your rudders. If you disable the limiter system, exactly as Ironhand found, at speeds at or above roughly 700 Km/h your rudders will break on full deflection. There are plenty of reasons to disable the AOA/G limiter under certain conditions and in certain situations, but under all those conditions & situations you are very unlikely to need to use your rudders. At nearly any speed the DCS Su-27 will perform ~95% co-ordinated turns for you. The only time you need to manually adjust the rudders are for cross wind landings and maybe during some of the more exotic WVR manoeuvres. Under normal conditions, even high AOA, the ACS will deal with rudder inputs for you, even cross-coupling yaw & roll channels to provide better roll control at high AOA. Feet off the rudders!

Edited May 29, 2018 by DarkFire