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Philipscdrw
03-07-2005, 09:00 AM
Hi all

I started flying about in gliders a few months ago, and one of the really noticable differences between Il-2 and real-life gliders is that, to turn in a glider, you need to use a lot of rudder to start and maintain the turn. To make a turn, (in the PZL Bocian, renown for its woefully underpowered rudder), you need to practically floor the rudder pedal, apply about 1/2 inch of stick movement and some back pressure, then (IIRC) centre the stick and unload most of the rudder. Using the stick by itself results in the upwards-bound wing slowing down, because it's producing more lift, which results in adverse yaw.

I know powered aircraft fly differently, what with the engine and propwash etc, but in Il-2 the aircraft will remain co-ordinated without any rudder input at all. Effectively all the rudder is used for is to slew the nose to aim the guns, in my experience of PF. This is actually giving me a really bad habit of using stick without rudder, which is bad news in a glider - the ailerons must always be used in conjunction with rudder for co-ordinated flight (i.e. if you don't want to fly at 20 degrees to the airflow with the ASI reading 30mph because of the indirect airstream, and the instructor swearing in the back seat, and the aircraft stalling and spinning into a hillside...)

Does anyone with experience of propellor-powered flight want to comment on the rudder in Il-2?

Plebanos
03-07-2005, 09:22 AM
hi!
forget everything what you have learnt in gliders. this sims rudder pedals do not work the way real rudders work at all. movements of the airplane around its vertical axis are pretty much off base in this sim.
i tried to use pedals in the game but because they work 100000% differently from RL, i have given up. i am yet to see a simulator where rudder actually works the way it should....

ruxtmp
03-07-2005, 09:55 AM
100% agreement rudders are completely unrealistic in this game when compared to gliders or power aircraft. My brother plays quite well without any rudder at all he uses the keyboard to rudder inputs for ground steering and spin recovery. As a matter of fact I have been limiting my game time as I have started to pick up some dangerous habits. Using ailerons to correct a dropping wing during stall onset works great in game but in real life this would just aggrevate the stall condition and can get you killed.

VW-IceFire
03-07-2005, 05:09 PM
I use my rudder all the time. Mind you, its on a twist axis. Not quite like the real thing eh?

BaldieJr
03-07-2005, 06:20 PM
Realism matters only when making a point. If you are trying to counter point, the best thing to do is remind everyone that this is just a game.

http://forums.ubi.com/images/smilies/53.gif

3.JG51_BigBear
03-07-2005, 06:52 PM
I've never had the opporunity to fly the real thing, but even my scale R/C planes need a considerable amount of rudder to do scale looking turns. In game the rudder does seem to speed up turning and roll.

Philipscdrw
03-08-2005, 06:20 AM
Has anyone here with real-world flight experience played X-Plane?

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>ruxtmp
As a matter of fact I have been limiting my game time as I have started to pick up some dangerous habits. Using ailerons to correct a dropping wing during stall onset works great in game but in real life this would just aggrevate the stall condition and can get you killed. <HR></BLOCKQUOTE>

I'm also worried for the same reason. Recent flights in gliders, the instructor tells me off for not using the rudder enough, and making uncoordinated inputs by using ailerons alone - and I realise that's the way I fly in PF... I love the sim, but I don't want to risk my spine by flying real aircraft to PF style...

LEXX_Luthor
03-08-2005, 07:42 AM
One thing you could do is try FB/PF aircraft with engine off. Pick a "glider" type...Ki~43 maybe. Fish around for something. I started doing some glide tests long ago but never finished.

I use my racing pedals mostly just for gunnery, ground handling and takeoff, and sometimes on landing approach. Even manuevering around I don't need it much in the sim except at high AoA/ low speed situations to help get nose down.

Alot of Oleg's testers are real life pilots, and they seem to stay alive. http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif On the other hand if you are still learning then yes this could be a Problem if you spend ALOT of time over the PF.

This is air combat simulation not Peace Time Civil simulation or Test Pilot Sim (X~Plane) with only one (1) plane in the sky. The funny thing is we all know this, or we wouldn't even be here. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Philipscdrw
03-08-2005, 03:15 PM
I'm still learning, I have a grand total of *searches for logbook* - excuse me a minute - *hires Sherpa guide and ascends Mount Clutter* - um, I can't find my logbook. I have approximately 2 hours gliding experience, over 15 flights (because we don't get thermals in winter, or an aerotow while the tug is awaiting CoA) so yes, you could say I'm still learning...

I know that PF has a lot to think about other than the control pressure on the rudder pedals, but it's easy to take everything else for granted!

I will now investigate a way to reduce the centre-point detent on the CHPro pedals - that's quite unrealistic for the aircraft I fly, and makes small rudder input quite counter-intuitive...

WB_Outlaw
03-08-2005, 08:39 PM
Adverse yaw is not due to the outboard wing slowing down, it's caused b/c the outboard wing goes faster. Remember, V=wr where V=velocity(ft/sec), w=angular velocity (rad/sec), and r=radius(feet). The outboard wing is farther away (larger r) from the center of the turn and thus goes faster.

If you watch the ball, most aircraft in the game will slip unless rudder input is applied in a turn.

-Outlaw.

Philipscdrw
03-09-2005, 04:32 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by WB_Outlaw:
Adverse yaw is not due to the outboard wing slowing down, it's caused b/c the outboard wing goes faster. Remember, V=wr where V=velocity(ft/sec), w=angular velocity (rad/sec), and r=radius(feet). The outboard wing is farther away (larger r) from the center of the turn and thus goes faster.

If you watch the ball, most aircraft in the game will slip unless rudder input is applied in a turn.

-Outlaw. <HR></BLOCKQUOTE>

Not sure if I follow you here. In a glider, if you roll to the right, the nose moves to the left if you don't apply rudder. This is because raising a wing involves increasing lift on that wing with the aileron, which increases the drag on that wing and swings the glider round.

Redwulf 32 - Nis
03-09-2005, 05:34 AM
Hi Philipscdrw

Having flown gliders for almost 40 years now, it's always nice to see somebody taking up this great hobby - welcome aboard buddy!

To answer your first question regarding the obvious difference in required rudder input you have to consider that, in your standard WWII fighter, the ratio between the cruising speed and your min. flying speed is much higher than in the Bocian. Control authority of your tail surfaces increases with the SQUARE of the increase in speed - this means you're getting tremendous authority out of you vert. stab. at normal cruising speed - which means no, or at least very little rudder input is needed to execute a 'clean' turn at speed. The vert. stab. takes care of that for you (incidently, it's the reason it's there ;-) ) Try slowing down for an approach to approx. 180 km/hr in a Bf-109 (flaps, gear down 30-40% power, nose high) and now try turning - you'll notice that a fair amount of rudder is indeed needed now! Another aspect of the glider is that the high aspect ratio wings results in a high moment of inertia around the yaw axis which, of course, requires a heavy foot on the pedals when entering/leaving a turn. You'll discover, when you get to the high speed exercises in the Bocian that when you fly faster, you won't be using as much rudder for turns as you're used to at lower speeds. You are of course also right in the adverse yaw contributed by the ailerons.

Regarding the CH-pedals. I bought a set about half a year ago and the foolish mid-position detent drove me absolutly nuts - who the **** would devise such a thing? Certainly not a pilot. If my (real-life) plane had a detent like that it would be off the ramp and in the shop in seconds flat!

I decided to remedy it myself (and void the 3 year garantee at the same time) and took the thing apart and removed the two protrusions from the bottom cover that give you the detent (you'll see what I mean when/if you decide to modify it).

Word of caution required!!!
Carefull now, it looks great on the outside - inside it's flimsy and clumsily made. Sort of like opening a box full of springs - if you don't watch it, you'll have parts going in all directions - you have been warned.

After re-assembling it it's great without the detent (maybe tactile feedback is a tad weak, I was considering putting in stronger springs but I've gotten used to it now)

Hope this helps - cya around

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Redwulf__32
(ADanishGliderPilot + CFIG)

DGC763
03-09-2005, 02:18 PM
Redwulf 32 is correct. The following is a description of adverse yaw.

Adverse Yaw: The downgoing wing will experiencea a new realtive wind and an increase in angle of attack. The inclination of the lift vector produces a component force foward on the the downgoing wing. The upgoing wing has its lift inclined with a component force aft. The result is a yawing moment opposite the to the direction of roll. The will be most prevelant at high coefficents of lift.

As to the people who don't use rudder like they have to do in a real airplane. solution: Find an airplane that has a yaw damper or FBW, like me. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

stef51
03-09-2005, 02:31 PM
Any tip for the input values for a joystick with rudder twist handle?

I find that the rudder in game does not move at the same speed that you can twist the joystick. Maybe to simulate pressure but it sure is hard to aim with all that left-right turning trying to aim...

Stephen

jeanba2
03-10-2005, 12:06 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Redwulf 32 - Nis:
Hi Philipscdrw

Having flown gliders for almost 40 years now, it's always nice to see somebody taking up this great hobby - welcome aboard buddy!

To answer your first question regarding the obvious difference in required rudder input you have to consider that, in your standard WWII fighter, the ratio between the cruising speed and your min. flying speed is much higher than in the Bocian. Control authority of your tail surfaces increases with the SQUARE of the increase in speed - this means you're getting tremendous authority out of you vert. stab. at normal cruising speed - which means no, or at least very little rudder input is needed to execute a 'clean' turn at speed. The vert. stab. takes care of that for you (incidently, it's the reason it's there ;-) ) Try slowing down for an approach to approx. 180 km/hr in a Bf-109 (flaps, gear down 30-40% power, nose high) and now try turning - you'll notice that a fair amount of rudder is indeed needed now! Another aspect of the glider is that the high aspect ratio wings results in a high moment of inertia around the yaw axis which, of course, requires a heavy foot on the pedals when entering/leaving a turn. You'll discover, when you get to the high speed exercises in the Bocian that when you fly faster, you won't be using as much rudder for turns as you're used to at lower speeds. You are of course also right in the adverse yaw contributed by the ailerons.



Hope this helps - cya around

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Redwulf__32
(ADanishGliderPilot + CFIG) <HR></BLOCKQUOTE>

This is exactly my opinion, though your superior experience makes you tell it much better than I can.
And as you say, it is always nice to see glider pilots http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif
But also, if the rudder is on the joystick (for il2 obviously), it is much more difficult to make a good coordination between stick and rudder.
I often surprise myself desperatly pushing on the floor with my foot, especially on takeoff

Philipscdrw
03-10-2005, 08:03 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Redwulf 32 - Nis:
Hi Philipscdrw

Having flown gliders for almost 40 years now, it's always nice to see somebody taking up this great hobby - welcome aboard buddy!

To answer your first question regarding the obvious difference in required rudder input you have to consider that, in your standard WWII fighter, the ratio between the cruising speed and your min. flying speed is much higher than in the Bocian. Control authority of your tail surfaces increases with the SQUARE of the increase in speed - this means you're getting tremendous authority out of you vert. stab. at normal cruising speed - which means no, or at least very little rudder input is needed to execute a 'clean' turn at speed. The vert. stab. takes care of that for you (incidently, it's the reason it's there ;-) ) Try slowing down for an approach to approx. 180 km/hr in a Bf-109 (flaps, gear down 30-40% power, nose high) and now try turning - you'll notice that a fair amount of rudder is indeed needed now! Another aspect of the glider is that the high aspect ratio wings results in a high moment of inertia around the yaw axis which, of course, requires a heavy foot on the pedals when entering/leaving a turn. You'll discover, when you get to the high speed exercises in the Bocian that when you fly faster, you won't be using as much rudder for turns as you're used to at lower speeds. You are of course also right in the adverse yaw contributed by the ailerons.

Regarding the CH-pedals. I bought a set about half a year ago and the foolish mid-position detent drove me absolutly nuts - who the **** would devise such a thing? Certainly not a pilot. If my (real-life) plane had a detent like that it would be off the ramp and in the shop in seconds flat!

I decided to remedy it myself (and void the 3 year garantee at the same time) and took the thing apart and removed the two protrusions from the bottom cover that give you the detent (you'll see what I mean when/if you decide to modify it).

Word of caution required!!!
Carefull now, it looks great on the outside - inside it's flimsy and clumsily made. Sort of like opening a box full of springs - if you don't watch it, you'll have parts going in all directions - you have been warned.

After re-assembling it it's great without the detent (maybe tactile feedback is a tad weak, I was considering putting in stronger springs but I've gotten used to it now)

Hope this helps - cya around

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Redwulf__32
(ADanishGliderPilot + CFIG) <HR></BLOCKQUOTE>

Thanks! I did take the pedals apart once, in an attempt to work out why the toe-brakes were spiking, and it did take me all evening to put it back together again... not much fun!

Unfortunately I'll not be gliding for the next 6/7 weeks as I'm home for Easter. But at least I'll be able to play SH3 at that time!

(By the way, the 'AnotherBritGliderPilot' in my sig is a reference to a chap on the LO-MAC forums called BritGliderPilot...)

JG77_Roland
03-10-2005, 11:10 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Redwulf 32 - Nis:
Hi Philipscdrw

Having flown gliders for almost 40 years now, it's always nice to see somebody taking up this great hobby - welcome aboard buddy!

To answer your first question regarding the obvious difference in required rudder input you have to consider that, in your standard WWII fighter, the ratio between the cruising speed and your min. flying speed is much higher than in the Bocian. Control authority of your tail surfaces increases with the SQUARE of the increase in speed - this means you're getting tremendous authority out of you vert. stab. at normal cruising speed - which means no, or at least very little rudder input is needed to execute a 'clean' turn at speed. The vert. stab. takes care of that for you (incidently, it's the reason it's there ;-) ) Try slowing down for an approach to approx. 180 km/hr in a Bf-109 (flaps, gear down 30-40% power, nose high) and now try turning - you'll notice that a fair amount of rudder is indeed needed now! Another aspect of the glider is that the high aspect ratio wings results in a high moment of inertia around the yaw axis which, of course, requires a heavy foot on the pedals when entering/leaving a turn. You'll discover, when you get to the high speed exercises in the Bocian that when you fly faster, you won't be using as much rudder for turns as you're used to at lower speeds. You are of course also right in the adverse yaw contributed by the ailerons.

Regarding the CH-pedals. I bought a set about half a year ago and the foolish mid-position detent drove me absolutly nuts - who the **** would devise such a thing? Certainly not a pilot. If my (real-life) plane had a detent like that it would be off the ramp and in the shop in seconds flat!

I decided to remedy it myself (and void the 3 year garantee at the same time) and took the thing apart and removed the two protrusions from the bottom cover that give you the detent (you'll see what I mean when/if you decide to modify it).

Word of caution required!!!
Carefull now, it looks great on the outside - inside it's flimsy and clumsily made. Sort of like opening a box full of springs - if you don't watch it, you'll have parts going in all directions - you have been warned.

After re-assembling it it's great without the detent (maybe tactile feedback is a tad weak, I was considering putting in stronger springs but I've gotten used to it now)

Hope this helps - cya around

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Redwulf__32
(ADanishGliderPilot + CFIG) <HR></BLOCKQUOTE>

Hello Redwulf32

Basicly you are correct, but using Rudder in FB is still way off.
Auhtority of the vertical stab increase with airspeed, but the amount of correction to fly straight or clean if you dont trimm at all have to increase also. Especialy for Planes without vertical stab trimm like the BF109. You should need much more rudder input (up to the full right so far i know) to fly straight in a dive or at high Speed. In PF You dont need any input at all in the BF109 if you are using 70 to 75% Power settings, there is no difference if you are cruising at 350Km/h or into a dive at 700+ Km/h.
In a WWII fighter you still have to perform a lot of footwork to fly properly in Air Combat Manovers because of the big speed rage where it take place.

Brechstange
03-10-2005, 04:29 PM
Same experience that i have ..

the rudders don't work RL at all....
But as well as the physics are not real life ..
a ..
what the **** http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif
Brechstange

Cragger
03-12-2005, 10:00 AM
I would suspect this has more to do with a 'play' issue than a lack of understanding of how it works. Think of it this way.

Would you like in a game to have to constantly provide a rudder input to even fly in a decent straight line or turn? Now for those that have rudder pedals take those away, how much less 'fun' would it be to do that all the time while trying to do other things with a toggle or twist stick? Ok, now take away a toggle and twist stick, would you enjoy doing this all the time with keyboard inputs?

Sometimes.. even in a sim reality becomes a negative, IL2 is not about teaching one how to fly, that is left to actual flight instructors and flight training. It is about simulating the 'experience' of flight and aerial combat of the era.

I can tell you that if I HAD to give constant rudder input to even fly say a 109 decently since it has no rudder trim I'd never fly it, it wouldn't be fun, it would be a tiresome chore.

TX-EcoDragon
03-14-2005, 01:19 PM
I agree that at speed the amount of control surface travel needed goes way down across the board, however there is still PLENTY of need for quad busting leg work when rolling, or in particular in roll reversals in these WWII fighers even at speed.

As far as what casues adverse yaw, the most commonly accepted "cause" has been mentioned by Philipscdrw but like amny ofther aspects of the physics of glight people will have different ideas that make a certain amount of sense, and the truth is most probably a combination of multiple factors. . . in any case the aircraft will yaw to teh outside of the turn and this effect is mroe and more pronounced with greater aileron surface travel. . . and really noticable when doing something like scissors.

As far as how the sim models it, just like the initial post suggested the rudder work required in this sim, and really any sim out there, is not all that realistic, and in this case, we have what feels a lot like Microsoft's "Auto-Coordination" on all the time. Piston fighters wont require quite as much as a glider will, at elast at normal flying speeds, but they are by no means feet on the floor affairs as they are in the sims!



<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Redwulf 32 - Nis:
Hi Philipscdrw

Having flown gliders for almost 40 years now, it's always nice to see somebody taking up this great hobby - welcome aboard buddy!

To answer your first question regarding the obvious difference in required rudder input you have to consider that, in your standard WWII fighter, the ratio between the cruising speed and your min. flying speed is much higher than in the Bocian. Control authority of your tail surfaces increases with the SQUARE of the increase in speed - this means you're getting tremendous authority out of you vert. stab. at normal cruising speed - which means no, or at least very little rudder input is needed to execute a 'clean' turn at speed. The vert. stab. takes care of that for you (incidently, it's the reason it's there ;-) ) Try slowing down for an approach to approx. 180 km/hr in a Bf-109 (flaps, gear down 30-40% power, nose high) and now try turning - you'll notice that a fair amount of rudder is indeed needed now! Another aspect of the glider is that the high aspect ratio wings results in a high moment of inertia around the yaw axis which, of course, requires a heavy foot on the pedals when entering/leaving a turn. You'll discover, when you get to the high speed exercises in the Bocian that when you fly faster, you won't be using as much rudder for turns as you're used to at lower speeds. You are of course also right in the adverse yaw contributed by the ailerons.

Regarding the CH-pedals. I bought a set about half a year ago and the foolish mid-position detent drove me absolutly nuts - who the **** would devise such a thing? Certainly not a pilot. If my (real-life) plane had a detent like that it would be off the ramp and in the shop in seconds flat!

I decided to remedy it myself (and void the 3 year garantee at the same time) and took the thing apart and removed the two protrusions from the bottom cover that give you the detent (you'll see what I mean when/if you decide to modify it).

Word of caution required!!!
Carefull now, it looks great on the outside - inside it's flimsy and clumsily made. Sort of like opening a box full of springs - if you don't watch it, you'll have parts going in all directions - you have been warned.

After re-assembling it it's great without the detent (maybe tactile feedback is a tad weak, I was considering putting in stronger springs but I've gotten used to it now)

Hope this helps - cya around

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Redwulf__32
(ADanishGliderPilot + CFIG) <HR></BLOCKQUOTE>