52 minutes ago, strider1 said:

What about the weathervaning bug ?

 

10 hours ago, MortenM said:

We are working with austin on the ground effect pitching moment, at this point it is uncertain if the new model will make it into 11.10

I was about to ask that. Taxying to the runway with even 10kts is damn near impossible if it is across your path.

Chris

6 hours ago, tutmeister said:

 

I was about to ask that. Taxying to the runway with even 10kts is damn near impossible if it is across your path.

Chris

No. You are doing something wrong.

If you are experiencing obvious weird behavior - especially in a beta - the first thing you should do is delete the XP prefs files and try again.

Not just beta, this is a long standing weather vaning bug that overpowers rudder and nosewheel like you are in a hurricane.

I'll post a video later but this is something that has been raised many times and is easy to find with a search.

It was slightly addressed in that when the parking brakes are on then you no longer slide about but as soon as they are released and you are rolling then the wind affects you.

Chris

12 minutes ago, tutmeister said:

Not just beta, this is a long standing weather vaning bug that overpowers rudder and nosewheel like you are in a hurricane.

I'll post a video later but this is something that has been raised many times and is easy to find with a search.

It was slightly addressed in that when the parking brakes are on then you no longer slide about but as soon as they are released and you are rolling then the wind affects you.

Chris

Hi Chris,

The excessive weathervaning that was a problem in the past was adressed in the initial beta run of XP11.

The reports we still get from time to time are from users that fly with a mouse or the keyboard, fail to assign/calibrate their rudder pedals properly, inadvertantly set their airport surface to icy or set up the wind wrong (and have subsequently much higher winds than expected).

I can taxi all default aircraft in winds exceeding their maximum crosswind limits with no problem.

If this does not work for you, I encourage you to check for any issues as suggested above.

Looking forward to the video, please do not forget to output the datarefs for nosewheel/rudder deflection and wind/speed so we can see what is going on.

Jan

 

Hey thanks for the input Jan, I'll check everything through and if there is still an issue I'll post a video.

Chris

I take it back!

For ages I've been trying betas and cursing as things weren't changing. Deleted only the xplane prefs and reloaded and things are much better. Can now taxy in a 15kts crosswind! :)

Thanks for the advice all of you.

Chris

8 hours ago, Janov said:

The excessive weathervaning that was a problem in the past was adressed in the initial beta run of XP11.

Nope, it's still there. Here's the easiest way to reproduce it. Let me know if someone can't reproduce this, and I'll look further, but I just deleted the xp pref file to be sure, my controls are perfectly calibrated (showing no jitter in the direct XP data readout), and this is the latest beta:

1. Load the Cirrus jet on a runway 90 facing east. With the Cirrus, there is no prop torque, P-factor, etc.
    
2. Set clear weather and a 15 kt. crosswind from 0 degrees.
    
3. Release the brakes, increase throttle to a very slow taxi with feet off the pedals and hands off the yoke. 
    
4. The Cirrus Jet will very quickly start to turn left into the wind, and slowly go off the runway to the left. 
    
5. Reset the flight with the 15 kt. crosswind coming from 180 degrees, repeat the procedure above, and the Cirrus Jet will now start to turn right into the wind, and slowly go off the runway to the right. 

Note that this also works with even lighter crosswinds like 5 kts. or 10 kts., it's just easier to see at 15 kts. Happens with all the light planes like the C172, but the Cirrus removes any prop issues (and even those aren't enough to prevent weathervaning into a crosswind in the opposite direction to prowash, etc.).

Again, my controls are showing steady calibration in the data output. There is nothing moving this plane off the runway in two completely opposite directions except the direction of the light crosswind. It's the only variable I'm changing in the test above.

47 minutes ago, Paraffin said:

Nope, it's still there. Here's the easiest way to reproduce it. Let me know if someone can't reproduce this, and I'll look further, but I just deleted the xp pref file to be sure, my controls are perfectly calibrated (showing no jitter in the direct XP data readout), and this is the latest beta:

1. Load the Cirrus jet on a runway 90 facing east. With the Cirrus, there is no prop torque, P-factor, etc.
    
2. Set clear weather and a 15 kt. crosswind from 0 degrees.
    
3. Release the brakes, increase throttle to a very slow taxi with feet off the pedals and hands off the yoke. 
    
4. The Cirrus Jet will very quickly start to turn left into the wind, and slowly go off the runway to the left. 
    
5. Reset the flight with the 15 kt. crosswind coming from 180 degrees, repeat the procedure above, and the Cirrus Jet will now start to turn right into the wind, and slowly go off the runway to the right. 

Note that this also works with even lighter crosswinds like 5 kts. or 10 kts., it's just easier to see at 15 kts. Happens with all the light planes like the C172, but the Cirrus removes any prop issues (and even those aren't enough to prevent weathervaning into a crosswind in the opposite direction to prowash, etc.).

Again, my controls are showing steady calibration in the data output. There is nothing moving this plane off the runway in two completely opposite directions except the direction of the light crosswind. It's the only variable I'm changing in the test above.

Errm, and what is wrong with that? Of course, any plane will weathervane into the wind, thats what they put those big fins in the back for!

You have to counter this with opposite rudder/nosewheel, this is totally normal.

Jan

 

2 hours ago, Paraffin said:

Nope, it's still there. Here's the easiest way to reproduce it. Let me know if someone can't reproduce this, and I'll look further, but I just deleted the xp pref file to be sure, my controls are perfectly calibrated (showing no jitter in the direct XP data readout), and this is the latest beta:

1. Load the Cirrus jet on a runway 90 facing east. With the Cirrus, there is no prop torque, P-factor, etc.
    
2. Set clear weather and a 15 kt. crosswind from 0 degrees.
    
3. Release the brakes, increase throttle to a very slow taxi with feet off the pedals and hands off the yoke. 
    
4. The Cirrus Jet will very quickly start to turn left into the wind, and slowly go off the runway to the left. 
    
5. Reset the flight with the 15 kt. crosswind coming from 180 degrees, repeat the procedure above, and the Cirrus Jet will now start to turn right into the wind, and slowly go off the runway to the right. 

Note that this also works with even lighter crosswinds like 5 kts. or 10 kts., it's just easier to see at 15 kts. Happens with all the light planes like the C172, but the Cirrus removes any prop issues (and even those aren't enough to prevent weathervaning into a crosswind in the opposite direction to prowash, etc.).

Again, my controls are showing steady calibration in the data output. There is nothing moving this plane off the runway in two completely opposite directions except the direction of the light crosswind. It's the only variable I'm changing in the test above.

15 knots 90° crosswind is not what I would call a light cross wind, and indeed some effect is to be expected. It is like driving a car, you make all the time small corrections, or you will go off the road, in this case the wind will work on the surfaces of the plane, and it will eventually turn against the wind, if you do nothing.

If this effect is exagerated or not in X-Plane, I can not tell (I am not a real pilot). But physics do command this behaviour.

Beta5 is out

2 hours ago, Janov said:

Errm, and what is wrong with that? Of course, any plane will weathervane into the wind, thats what they put those big fins in the back for!

You have to counter this with opposite rudder/nosewheel, this is totally normal.

There isn't that much surface area on the Cirrus Jet v-tail, and a lot of exposed surface in that raised roofline over the cabin forward of the wings. The plane weighs 6,000 lbs., and this will still happen (although it will take longer) with a 5 kt. crosswind. More importantly, the behavior is consistent with many different aircraft types with different amounts of exposed tail area, weight-on-wheels, etc.

I'd like to hear from more real pilots if this behavior is this strong in real life.

1 hour ago, Cyrex1984 said:

Beta5 is out

Beta five you say? :)

Off to do some downloading.

Chris

Flight instructors or plane owners chime in ! I have a little bit of crosswind time in a 172. I don't ever remember the plane wanting to weathervane into the wind on the takeoff roll/landing roll. I do remember the wing wanting to roll over on a landing and a takeoff roll. Crosswinds in the sim are manageable with rudder pedals, but it seems way excessive.

1 hour ago, strider1 said:

Flight instructors or plane owners chime in ! I have a little bit of crosswind time in a 172. I don't ever remember the plane wanting to weathervane into the wind on the takeoff roll/landing roll. I do remember the wing wanting to roll over on a landing and a takeoff roll. Crosswinds in the sim are manageable with rudder pedals, but it seems way excessive.

Aileron to the wind, rudder to keep directional control that all I really know :) If my student can't do a good job then I correct it. Other than that I try to keep my airplane on the center-line the best I can. I don't really let 172 do anything until we in the air, so call me a chicken - my personal minimums are rather high :)

Now as soon as we get airborn airplane weathervane immediately. I actually let my students to crab while climbing, and actually teach them don't pay attention to cowling but rather track the flight path. My observation that 172 (clean) will start little weathervane as low as 5+ kts direct x-wind