Yaw � how to use it?

[Teilnehmer]

I have little experience in piloting planes so my question is possibly a silly one.

When I fly a plane and want to turn right, for instance, I roll clockwise and pitch. That works.

But there’s also the yaw control. How am I supposed to use it?

When I press the D key, the plane seems to be changing its attitude but it changes back when I release the key. If I hold the key for a longer time, the plane starts to roll, pitch and behave strangely.

What is the yaw control needed for? How should I use it? How should I build a plane to use the yaw control effectively?

[Brofessional]

Yaw is generally for fine control in keeping or changing a heading. Since there's no wind in stock KSP you don't even really need yaw much of the time.

[Overland]

yaw is rudder control generally..if you have one at all on the plane

the rudder much like a ship points the planes nose in a direction.. it can be used in combination with roll to properly coordinate a turn. eg plane rolls to turn but you dont have to pull back to start the turn..

with the new aerodynamics its all possible but also generally not needed. especially if you havent got a joystick with a dedicated rudder axis.. any control surface setup with all 3 properties will likely help anyway

also useful with helicopters for the same reason

becareful though as overuse on or near stall can cause loss of control which you might not be able to recover

in the RCS term if setup. it would fire opposite thursters and flatly rotate the craft on its axis

I did planes before Trains

[Carsogen]

YAW! HUGH! Good god! What is it good for? Absolutely nothing (except lateral axis attitude control)!

[Hagen von Tronje]

On especially spry planes, I use yaw in combination with pitch to perform extremely sharp turns. Same technique as you describe, just a much tighter turn radius.

[LordFerret]

I have little experience in piloting planes so my question is possibly a silly one.

When I fly a plane and want to turn right, for instance, I roll clockwise and pitch. That works.

But there’s also the yaw control. How am I supposed to use it?

When I press the D key, the plane seems to be changing its attitude but it changes back when I release the key. If I hold the key for a longer time, the plane starts to roll, pitch and behave strangely.

What is the yaw control needed for? How should I use it? How should I build a plane to use the yaw control effectively?

Just like piloting a plane (a little Cessna for example), in a turn you'd roll and yaw - coordinated flight (see here and here), rudder and aileron. At high speeds, like with jets, rudders are little used (and usually computer controlled to compensate adverse yaw in aileron turns)... they don't serve much unless you're under 300kts (based on what I know of flying an F-16), on the ground keeping you on the runway centerline.

[Alshain]

The natural occurrence while making a banking maneuver is to both pitch and turn.

1. You could avoid the pitch by turning the wings perpendicular to the ground, but that isn't a great idea, especially if you are flying a passenger plane where passengers would be less tolerant of being on their side. It also poses a greater risk of stall.

2. Another option is to allow the pitch and then once the turn is complete pitch back (or alternatively, make several smaller banks fixing the pitch between each one). This too could be vomit inducing and if your speed isn't great, pitching is still a bad idea and cause a stall (remember, banking naturally slows you down).

3. The last option is the primary function of an active rudder. As you bank and pitch up, you gently slide the yaw in the direction of the artificial horizon. This allows you to perform the bank without changing pitch and without being completely on your side. I will say that if you fly with a keyboard, this is more difficult than it's worth, use option 2 (or really, since it's a game, option 1 works too, I don't like it though). If you use a flight stick it's like second nature, use Yaw.

Yaw can be used in real life to make minor course corrections, but not big turns, and it isn't the primary function. Yaw is optional for flight, you do not need it, but it is good to have and that is why most modern planes have it. It makes for a smoother ride.

Edited August 14, 2015 by Alshain

[Geschosskopf]

For rockets, you use yaw during ascent to get the gravity turn started . It's also used a lot when lining up for a maneuver node and when docking.

For airplanes, all my planes require coordinated controls during turns. If I bank less than 90^, applying pitch not only turns the plane but makes it go up, so I use bottom rudder to keep the nose on the horizon, just like in a real plane. Another excellent use of yaw for planes is to sideslip in for a steep but slow descent into a short landing field between various terrain obstacles. For this, you combine yaw in 1 direction with roll in the opposite direction while applying a bit of up pitch to keep the nose more or less level. And down you come steeply without gaining speed. Again, just like a real plane. Finally, another essential use for yaw is making sure your nose is directly on the prograde marker just before the wheels hit the gound, which tends to prevent tumbling on landing. And of course if you're into aerobatics, you need gobs of yaw to do snaprolls, hammerheads, and lomcovaks .

NOTE: I fly with just the keyboard, no joystick, but I find that quite enough.

For rovers, (assuming you have remapped the rover steering to other keys than WASD), you can use torque yaw in conjunction with steering to turn tighter at higher speeds.

[LordFerret]

The natural occurrence while making a banking maneuver is to both pitch and turn.

1. You could avoid the pitch by turning the wings perpendicular to the ground, but that isn't a great idea, especially if you are flying a passenger plane where passengers would be less tolerant of being on their side. It also poses a greater risk of stall.

2. Another option is to allow the pitch and then once the turn is complete pitch back (or alternatively, make several smaller banks fixing the pitch between each one)

3. The last option is the primary function of an active rudder. As you bank and pitch up, you gently slide the yaw in the direction of the artificial horizon. This allows you to perform the bank without changing pitch and without being completely on your side. I will say that if you fly with a keyboard, this is more difficult than it's worth, use option 2 (or really, since it's a game, option 1 works too, I don't like it though). If you use a flight stick it's like second nature, use Yaw.

Yaw can be used in real life to make minor course corrections, but not big turns, and it isn't the primary function. Yaw is optional for flight, you do not need it, but it is good to have and that is why most modern planes have it. It makes for a smoother ride.

I've not tried this yet - is it even possible in KSP? ... to auto-coordinate (tie together) aileron/roll and rudder/yaw?

[Alshain]

I've not tried this yet - is it even possible in KSP? ... to auto-coordinate (tie together) aileron/roll and rudder/yaw?

Auto-coordinate? As in have one button do it all? Probably not, it would depend on how big your banking is and also how much pitch your ailerons provide (which depends on the plane construction, and in KSP that's a big variable). But with a flight stick it is certainly possible manually, just roll then pull back and twist the stick at the same time. It's very easy, I do it all the time.

[Geschosskopf]

I've not tried this yet - is it even possible in KSP? ... to auto-coordinate (tie together) aileron/roll and rudder/yaw?

I do coordinated turns (using the keyboard) as follows:

1. Set the bank I want. SAS holds it for me.

2. Keeping my eye on the navball, I tap and/or hold both S (for up) and either A or D (for rudder) both simultaneously and independently, as needed to keep the nose where I want it vertically during the turn.

[LordFerret]

Auto-coordinate? As in have one button do it all? Probably not, it would depend on how big your banking is and also how much pitch your ailerons provide (which depends on the plane construction, and in KSP that's a big variable). But with a flight stick it is certainly possible manually, just roll then pull back and twist the stick at the same time. It's very easy, I do it all the time.

I have a stick but it's not hooked up to this machine (it's on my flightsim machine). Yes, having one button/key operate both. I know flightsims offer it (good for the beginner). I'll have to play around and see if that's possible, I've just the small jet to try it out on. Thanks.

[Alshain]

I'm not saying you can't do it with a keyboard, but the keyboard is so overly sensitive (On or Off, nothing in between) compared to an analog control that you can just barely nudge to get a nice smooth turn. Even tapping I'd imagine it's a bit shaky. Does that matter? Well it does to me, but I may not be the best one to ask

[LordFerret]

Geschosskopf, I pretty much do the same now... although flying around low altitude through mountain passes and such, it becomes a two-handed endeavor.

[Alshain]

I have a stick but it's not hooked up to this machine (it's on my flightsim machine). Yes, having one button/key operate both. I know flightsims offer it (good for the beginner). I'll have to play around and see if that's possible, I've just the small jet to try it out on. Thanks.

But the planes in flight sim are balanced for it, KSP's construct-a-craft format is going to make every plane different. The slightest change in mass, position of the elevons, or really just about anything can make you have too much yaw or not enough yaw. With an analog or an independent keyboard key, you are in control. With pitch and yaw on the same button, you would have trouble getting the two harmonious.

[LordFerret]

But the planes in flight sim are balanced for it, KSP's construct-a-craft format is going to make every plane different. The slightest change in mass, position of the elevons, or really just about anything can make you have too much yaw or not enough yaw.

...and thus the challenge of building a nicely balanced jet!

[Alshain]

...and thus the challenge of building a nicely balanced jet!

Lol, well good luck then. This might be possible if you were using FAR, if I recall it allows you to custom set a control surface's deflection angle so you can adjust for more or less yaw on a per-plane basis.

- - - Updated - - -

Still going to be hard though, you will have to always bank at the same angle.

[Teilnehmer]

Another question.

I have a spaceplane. I don’t use the yaw control in it manually, but I use SAS. Is it advisable to have a rudder (for SAS to use it to make flight stable), or would it be better to use a simple vertical fin without any yaw control.

[Sharpy]

When I press the D key, the plane seems to be changing its attitude but it changes back when I release the key.

When you press D, your plane yaws and the prograde direction starts crawling towards your current heading. The moment you release it, the plane returns to prograde direction.

Also, one more problem with Yaw: since the tail fin is usually a single one sticking upwards, without symmetry, yaw induces a torque on the plane, causing roll.

Yaw is extremely useful though. If your rocket swerves off course left or right, use yaw to correct it.

[Alshain]

Another question.

I have a spaceplane. I don’t use the yaw control in it manually, but I use SAS. Is it advisable to have a rudder (for SAS to use it to make flight stable), or would it be better to use a simple vertical fin without any yaw control.

I don't think the SAS really uses Yaw on a horizontal launch spaceplane. It shouldn't need to if the plane is well built, it should hold it's heading fairly well.

[kreutzkevic]

1. You could avoid the pitch by turning the wings perpendicular to the ground, but that isn't a great idea, especially if you are flying a passenger plane where passengers would be less tolerant of being on their side. It also poses a greater risk of stall.

I remember the first time I did this in the first huge plane I built in the new aero environment. Dropped from the sky like a brick on top of the R&D center. Ahhh... Fun times...

[GoSlash27]

Another question.

I have a spaceplane. I don’t use the yaw control in it manually, but I use SAS. Is it advisable to have a rudder (for SAS to use it to make flight stable), or would it be better to use a simple vertical fin without any yaw control.

I definitely prefer having my vertical stabilizers uncontrolled. If your wings aren't perfectly level, SAS will cross-control. The longer you leave it in that state, the larger the yaw input becomes. This is not only inefficient, but also unstable. Whenever you touch a control, the SAS resets and the rudder goes temporarily neutral. This causes an overcorrection in both yaw and roll. In some cases, it can throw you out of control entirely.

If you leave the rudder uncontrolled, the plane will naturally weathervane into line so long as you have sufficient tail surface and leverage.

Best,

-Slashy

[martinborgen]

IRL, yaw keeps the G-indicator in the middle. Basically, when you bank turn, you don't need to bank 90 (or close to) degrees. Theoretically, one might think so (and yes if flying a fighter jet or so), but because of earths gravity and whatnot you dont bank that much - hence yaw to keep you turning nice.

[viktor19]

I find yaw the bane of my planes existence under nuFAR. However, under Stock Aeroâ„¢ it's perfectly okay. Just don't overdo it, like LordFerret said.

[sal_vager]

Popped over to Gameplay Q's

You don't strictly need yaw on a plane in KSP, a fixed rudder can be enough to help with stability if it's big enough, but something I like doing is flying planes with rudder and elevator only, no ailerons at all.

Edited August 14, 2015 by sal_vager