To Microsoft : Please Give Us A Realistic Rudder!

[Guest]

Correct me if I'm wrong, but in a forward slip, your wings are not level, but rather banked in the opposite direction of your rudder application. The banking cancels out the rudder, therefore your direction of flight is not changed. That is why it snapped back to the original heading.Also, please see my post #29 at the end.Russ

[Guest Smiley]

I just tried the C172 in MSFS2002 to check the rudder action/reaction. The simulation is very close to realistic IMHO. I have flown the C172SP in real life and have tested the rudders effects while in flight. During my flight training my instructor had me fly the pattern with rudders only in a C152. Once at pattern altitude I set the throttle to 2200 RPM for level flight and trimmed the ac. While on downwind I was controlling my direction with rudders only. By setting the throttle and trim for maintaining altitude. Once I crossed the numbers I reset the throttle to 1500 and 10 degrees of flaps with 1 rotation of trim (gripping the trim wheel from the top and rotating down once for each 10 kt of speed reduced/increased). Once my speed was set at 70kts I used enough right rudder to induce the yaw/roll that initiated the turn to base. This was not a coordinated turn but if my aileron cable were to snap I feel I could bring the ac down on or at least near a runway/field into the wind :). I did this same test in the MSFS C172SP with the same results. The only thing I saw that could be closer to realistic is the ability to use the trim wheel in a manner in which is closer to what I practice in real life. With the trim indicator in the take off position the ac would not climb at normal climb speed without pulling back on the yoke. I found I had to adjust the trim to a position well below the take off mark to reduce the stick force.

[Guest aca_dia]

Even if you only use enough ailerons to keep from losing control the nose will move back to the relative wind (I said forward slip because thats the commin reason for doing this). My description of why might not be 100% perfect aerodynamics, but its what happens in the real world! Today I tried it a bunch in a 172 and a PA-161 (Piper Cherokee) and I held it for up to 2 minutes and the same result occurred. If you hold it in long enough you wont snap back to the same heading, but since the aircraft is skidding the nose will always move back in that direction when you release the rudder causing the skid. You need to read up on aircraft stability and basic aerodynamics if you really want to understand why.

[Guest aca_dia]

Yep you are right if you hold rudder in for a while the aircraft will turn some and when the nose does move back upon rudder release it will not end up where it started. I

[Guest Ron Freimuth]

>>I find the >>rudder model is particularly good when side slipping the >>aircraft for cross wind landings. Seems just like the real >>thing.>>Yes, I remember a few months ago where I was side slipping >the default 172 (with Ron Friemuth's flight model) for some >testing and pics............. and it really did seem quite >authentic. >............>>L.Adamson I check slips to a landing in many of my flight models. And, I only have a twist grip Sidewinder. Beats using Ins/Del, as I had to do some years ago without any other rudder input device. Just the same, I could land with the rated X-Wind for the recent SEL's I've done. Does take a smooth technique on the twist rudder control. One thing I check is maximum sideslip angle I can get with crossed controls. 15 degrees seems about right and I've changed the Rudder strength in AIR files if necessary. It takes a test gauge or app to show that angle, though one could estimate it by watching how the ground passes by at an angle in a slip. Sometimes I'd slip strongly for landings in the real Cherokee I flew decades ago. I knew I was at the AC's limit when one rudder pedal was hit the floor. What makes things more challenging is that the wind is always varying and one has to control the approach with independent and varying aileron, rudder, pitch, and power commands. The big KSJC airport was closed to all traffic not long after I'd landed with a high crosswind one morning about 3 am. Hmm, wonder if they just waited until one bird made it back to its roost. --RAF

[bojote 20]

Tip:If you don't want the rudder snap-back just change yaw_stability variable to 10 in your aircraft.cfg file under the flight tunning section. You can 'slide' in the wind, don;t know if it is realistic but yaw_stability is what you want to play with.Rgds,

[Guest Stamatis]

Russ,Despite of what has been posted sofar, I do not believe your crticism of the rudder simulation and its effects in MSFS is unjustified.I am only refering to airliners, like the B737, not to GA aircraft.In most jet airliners the rudder is not used at all in flight until an engine fails. The rudder pedals are simply footrests in flight. One of the benefits of modern control systems is that spoilerons nullify aileron drag as you roll in and out of a turn, so rudder is not even required to overcome that.The principal use of the rudder pedals in a jet airliner are to keep straight on the take-off and landing roll...particularly in crosswind and to kill the yaw of asymmetric thrust with engine/s out.To get back to our issue, in an airliner, if a little constant rudder is kept applied, not enough to induce a bank, the track will keep changing continuously in a skidding turn. It will be a slow and ridiculous way to turn, but if you waited long enough you could turn through 360 degrees this way.How quickly will the track change depends on inertia: The aircraft will will only remain on its original track for as long as inertia dictates...a fully laden 747 for one or two seconds, a small regional jet hardly at all.I do not believe the above is properly simulated in FS2002, where there is very little change in track.Also, in real life if you release the pressure on the rudder pedal and let it come back to neutral, the nose of he aircraft will not return to its original heading at all... it will swing back to align with the new track of the moment.Again, I do not see that in MS FS2002, where it seems the nose snaps back to its original heading.So, as far as I am concerned, when it comes to modern jet airliners, the rudder/yaw simulation in FS2002 is not correct.Stamatis

[Guest Simpit]

Speaking of strong crosswinds....http://home.no.net/ossvense/Movies/TAP_321_ventos_fortes.asxDerek :-eek

[bojote 20]

Was that pilot shaking or the banking rocking motion was caused by the wind? impressive...

[badderjet 181]

OK at the beginning I must admit I have no time to read only one answer to this thread but anyways.I've been 6 hrs in a 737-300 sim at EDDF and tried also the rudder, which clearly HAD a 'snap back'. The only explanation I could imagine is that you can change the lateral attitude of the aircraft rather easily, but hell you can't change the whole flight path, that'd mean bring the whole 70 tons into a completely new direction. Might be somewhat difficult for the rudder... :-roll

[John_Cillis 2,406]

Glad to see that pilot finally got the idea.... I think that one's even better than the H.K. video that does the circuit here from time to time...-John

[Guest Ron Freimuth]

>I've been 6 hrs in a 737-300 sim at EDDF and tried also the >rudder, which clearly HAD a 'snap back'. The only >explanation I could imagine is that you can change the >lateral attitude of the aircraft rather easily, but hell you >can't change the whole flight path, that'd mean bring the >whole 70 tons into a completely new direction. Might be >somewhat difficult for the rudder... :-roll "Cn_beta, Yaw Moment - Sideslip" (Weathervane Stability) is the main parameter that keeps the AC headed into the relative wind. "Cn_dr, Yaw Moment - Rudder" can oppose the Weathervaning effect. Though, the rudder is normally used to aid Weathervane Stability in minimizing slip. "Cn-r, Yaw Moment - Yaw Rate (Damping)" damps down the rate Yaw changes. "Izz, Yaw Moment of Inertia" stores rotational Yaw energy, and thus slows down the effect of the others above. However, it also tends to keep a Yaw rate constant, once started. I set Cn_dr to get about 15 degrees of sideslip with 'crossed controls'. How fast the AC snaps back to zero sideslip depends mainly on the other three parameters above. Though, there are other Roll/Yaw related parameters that add coupling, so the end result can also involve some Roll. And, Roll generates the most significant force to turn an AC. Ron

[Guest]

Took the fell'er long enough to make his mind up about an abort. My geez call me a coward but I would have waved off long before that.http://www3.telus.net/dport1/Radar_small.gifRC3 - Just gotta' have it!http://www3.telus.net/dport1/Radar_small.gifhttp://www3.telus.net/dport1/dansig.jpg