Have to use the rudder to keep aircraft straight on the runway?

Hi

Is it normal that I have to use left and right rudder to keep the aircraft pointing in a straight line at takeoff ? I'm not taxing from the gate I'm just doing a free flight and my starting position is at the bottom of the runway. If I simply apply throttle I end up veering off to the left or right?

Cheers

Quick and simple, yes, as the others have noted above. It's the same principle as asking if you need the steering wheel on a car to keep it going straight.

If I simply apply throttle I end up veering off to the left or right?

Sounds as if you're using a piston single for this. Torque and P-effect (even gyro precession under certain circumstances) conspire to cause a left-turning tendency for piston singles. For some odd reason, I've sometimes seen that become right-turning in FS, but not always. You can go into your realism menu and disable those effects, if you're so inclined.

Using a modest mount of nose down elevator or trim can also mitigate the effect. Just remember that Vr may take longer or harder pull.

For more specific advice, be more specific.

It's funny you asked that question. I recently read an article in the AOPA magazine about that. The writer contends that everyone should fly a tail dragger at least a few times during initial flight training. Because learning to use the rudder during taxi with a tail dragger, in his opinion makes you more comfortable with the rudder when in flight.

His issue is you often see pilots who tip their wings a lot on final to line up and compensate for wind. He feels it's much more stable to make many of these corrections, if you know how to use the rudder instead.

There's also a useful thread here about the rudder-

https://www.flightsim.com/vbfs/showthread.php?286662-Plane-turns-automatically

I would agree with the writer, though "tip their wings" and "use the rudder instead" (in that context) don't sound like terms from AOPA magazine. There are two ways to track down final with a crosswind -- crabbing and slipping -- assuming you get the proper ground track out of it, and neither is wrong. Normally I'll crab most of the way down final, then change to a slip (to align the fuselage and wheel tracks with the runway) either on very short final, or in the flare, depending on the aircraft, the strength and gustiness of the crosswind, and whatever other factors may intrude at that moment.

If by "tip their wings a lot" you mean flying wing low and not intentionally slipping (probably skidding) vs. "use the rudder instead" meaning a proper slip, then that could make sense to me that he'd see a problem; certainly that's a dangerous way to do it, as well as sloppy and not all that effective vs. the proper ways.

But back to the "fly a taildragger" contention. In most cases (there are rare exceptions), of all the folks I ever checked out in various aircraft over the years, or flew with in other capacities, those with either tailwheel experience or sailplane (glider) experience were mostly better at rudder use and at general piloting "stick and rudder" skills than those without either background. One exception was a student I flew with (not mine, just a check) who was the only "natural" pilot I ever flew with. Another was a neighbor who flies for United, but also spent many years flying F-16s, yet had little or no light plane time. His rudder use was impeccable, which pleasantly surprised me.

I would agree with the writer, though "tip their wings" and "use the rudder instead" (in that context) don't sound like terms from AOPA magazine. There are two ways to track down final with a crosswind -- crabbing and slipping -- assuming you get the proper ground track out of it, and neither is wrong. Normally I'll crab most of the way down final, then change to a slip (to align the fuselage and wheel tracks with the runway) either on very short final, or in the flare, depending on the aircraft, the strength and gustiness of the crosswind, and whatever other factors may intrude at that moment.

 

If by "tip their wings a lot" you mean flying wing low and not intentionally slipping (probably skidding) vs. "use the rudder instead" meaning a proper slip, then that could make sense to me that he'd see a problem; certainly that's a dangerous way to do it, as well as sloppy and not all that effective vs. the proper ways.

 

But back to the "fly a taildragger" contention. In most cases (there are rare exceptions), of all the folks I ever checked out in various aircraft over the years, or flew with in other capacities, those with either tailwheel experience or sailplane (glider) experience were mostly better at rudder use and at general piloting "stick and rudder" skills than those without either background. One exception was a student I flew with (not mine, just a check) who was the only "natural" pilot I ever flew with. Another was a neighbor who flies for United, but also spent many years flying F-16s, yet had little or no light plane time. His rudder use was impeccable, which pleasantly surprised me.

I didn't attempt to quote AOPA. A quote includes quotation marks. I feel there are some who may not have your high and mighty knowledge and skill set who could learn more from reading more generic terms.

And yes, I know many taildragger guys who are better with "stick and rudder" skills too. Which was the point of my submission. BTW: those who have flown single main rotor choppers are very skilled with the "rudder" as well.

I didn't attempt to quote AOPA. A quote includes quotation marks. I feel there are some who may not have your high and mighty knowledge and skill set who could learn more from reading more generic terms.

 

And yes, I know many taildragger guys who are better with "stick and rudder" skills too. Which was the point of my submission. BTW: those who have flown single main rotor choppers are very skilled with the "rudder" as well.

Very well -- "tip your wings" then, and "use rudder instead," but please explain what you mean, presumably not just putting it in a bank or kicking rudder. It truly was not clear to me what you meant, and I'd hoped I could get an explanation of it, instead of you knocking my approach to trying to share information, or I hoped that at least you'd do some clarification.

A quote does, indeed, normally contain quotation marks, but I had the impression you intended to pass on the gist of what they said in the article (they would have been more clear), but your description was (to me, at least) sufficiently vague that I thought some sort of clarification was in order, since it was far from clear to me what action you were referring to.

I guess I'll have to stay out of any thread you're in, so that my information sharing attempts don't come across as "high and mighty." Sorry I treated you so badly...

thanks for the detailed replies! It looks like it is indeed normal to use rudder at takeoff. I'm relatively new to FSX and started off flying the Cessna trying to figure out how to actually fly, learn the lingo and fly point to point with the navigation systems. I've recently spent most of my time in the Learjet to get used to the twin engine setup.

As long as I know it's normal and I don't have something wrong with my stick I'm fine. A previous reply mentioned the F18 is notoriously difficult to keep straight. I did try and have a go in that and slipped completely off the runway at takeoff. I found it almost impossible to take off so I'm clearly not upto flying one of those yet!

I use a Logitech Joystick controller. I started having spastic rudder problems whenever the aircraft was on the ground. Turns out it is a problem with the controller. So, you may want to know this...? I Googled it and learned a lot about the Extreme 3D Pro. A somewhat minor issue but definitely a headache if you do not know how to recognize/correct it.

JR

I found the logitech 3d a bit difficult first too. Left-right (whether rudder or aileron), moving the stick slightly would have hardly any effect, then turning just a bit further the effect was huge. I Always ended up giving either to little imput or to much, and was constantly making corrections to corrections.

I read about a change in the fsx.cfg that could help.

In the:

[CONTROLS]

section, add the line:

stick_sensitivity_mode=0

It helped a lot, control got a lot more precise with that.

Enjoy,

il88pp.

I guess I'll have to stay out of any thread you're in, so that my information sharing attempts don't come across as "high and mighty." Sorry I treated you so badly...

I believe everyone on this board is here because we enjoy FSX. Obviously we come from different backgrounds, levels of training, levels of involvement, etc. I, and I don't believe most people intend to be a part of any ongoing argument.

A little civility & patience would go a long way here.

What just happened here?

not a clue...

To answer the original post...if you keep veering off the runway, that might be a trim issue, autopilot issue, or a balance issue. Since FSX does not exactly show balance all that well, I will have to say that it won't be that.

"... It looks like it is indeed normal to use rudder at takeoff..."

"... I've recently spent most of my time in the Learjet to get used to the twin engine setup...

"...As long as I know it's normal and I don't have something wrong with my stick I'm fine..."

Well. That's what the rudder is for, to be used.

The way to find out if everything is working as it should:

1) Disable online weather.

2) Set the weather theme to clear.

3) Position multi-engine plane on runway with 50% fuel evenly distributed and parking brake on.

4) With numpad lock OFF, tap the numpad 5 key. This centers your controls.

5) Press F1. This idles both engines (unless you've mistakenly enabled only one of the engines for control)

6) Go to external spot view and verify the tail rudder is centered and when you move the rudder, it moves smoothly and returns to center when released.

7) Return to cockpit and move the throttle the smallest amount and verify both/all throttles move together, return to idle.

Now full throttle down the runway, you should have no trouble tracking the center line with minimum or no rudder control (unless your rudder is too sensitive or the null zone is not large enough.)

Having verified all this, if you have trouble in the future:

1) You have some kind of wind component blowing your aircraft to one side.

Use shift-z to verify this. Planes do not track the runway by themselves with side wind without the pilot's assistance.

2) Your rudder or ailerons are not centered prior to your take off roll.

3) Your fuel is not loaded equally between L+R sides of the plane.

4) Your throttle is not moving both (or all) of the engines power evenly.

5) You have a misconfiguration or key mapping problem holding a differential brake activated.

6) The plane needs to be reloaded or the sim restarted.

7) You need to hold your tongue on the OTHER side of your mouth on take off.

-Pv-

I found the logitech 3d a bit difficult first too. Left-right (whether rudder or aileron), moving the stick slightly would have hardly any effect, then turning just a bit further the effect was huge. I Always ended up giving either to little imput or to much, and was constantly making corrections to corrections.

 

I read about a change in the fsx.cfg that could help.

In the:

[CONTROLS]

section, add the line:

stick_sensitivity_mode=0

 

It helped a lot, control got a lot more precise with that.

Enjoy,

il88pp.

Thanks for the idea---I could not locate fsx.cfg. I open the game file from the drive but do not see this file. The problem with the Logitech is literally physical--for some reason it goes goofy after a period of time and you have to "Exercise" the stick to relieve the condition--or so I learned from youtube videos. BUT-yes, the control stick also has the effect you mention.

JR

Hi Reddair,

The fsx.cfg is a 'hidden' file. Some files are hidden from the user, by Windows, as they should only be touched when you know what you are doing.

How to show hidden files in Windows 7:

Control Panel->Folder Options-> View tab

Under Hidden files and folders check "Show hidden files, folders, and drives".

Below that Uncheck "Hide extensions for known file types"

FSX file locations:

fsx.cfg, dll.xml, and GrantedRewards.BIN, {C:\Users\UserName\AppData\Roaming\Microsoft\FSX}

Your control settings = Standard.xml {C:\Users\UserName\AppData\Roaming\Microsoft\FSX\Controls}

Logbook.BIN and Flight Plan files

{C:\Users\UserName\Documents\Flight Simulator X Files}

scenery.cfg

{C:\ProgramData\Microsoft\FSX}

Taiwan! What does Taiwan have to do with rudder control. This week's AOPA news clip explains the pilot in Taiwan had a single engine failure on his twin engine airplane. He tried to correct his straight and level flight issue with the stick rather than the rudder. This put him into a "VMC Roll."

Basically the plane tries to turn towards the dead engine because of the drag difference, good engine to dead. Using the rudder to crab rather than using the stick, you can compensate. Provided you are at the VMC speed. (The speed at which the rudder is effective enough to correct the problem.)

If you use the stick, you induce even more drag on the dead engine side which often causes the plane to loop or roll inverted, if you don't hit the ground first. That's appears to be what killed those people in Taiwan. (Assuming I understood the article.) The pilot tried to correct his dead engine issue with his stick rather than his rudder.