Are spaceplanes turning right on runway?

[Numerlor]

Today I made 2 SSTOs with around 20 launches and every time I launch one it slightly steers to the right, when I was first playing with small (Mk0) Jets I got small steer to the right as well. Any real explanation for this? Downloads for 2 SSTOs mentioned: SSTO1  SSTO2

Edited February 15, 2017 by Numerlor
Why can't I just check it before posting and stop editing for 5 times

[Martian Emigrant]

Hi.

Sometime it just does.

I was told it was a bug. Maybe. IDK.

Try putting bigger gear on the ship. My feeling is that the gear are bending or jamming the wheels.

When I get it  adding more and bigger gear helps.

Sometime when building we think the gear are parallel and straight down but on closer inspection they aren’t.

Other times I found that my ship was too wobbly. Struts or autostruts are your friends.

 

ME

Edited February 16, 2017 by Martian Emigrant

[katateochi]

1 hour ago, Martian Emigrant said:

Struts or autostruts are your friends.

they (struts more than autostruts) can also be the cause of the pull to one side, if you have even 1 strut that is asymmetrically placed it can cause a pull to one side.  Sometimes when you place a strut with symmetry on and then reload the craft, or do an undo, then one of the pair may not connect in the same way (or at all) which can cause the issue.

Angled gears can also sometimes be the cause of a pull to one side.  If you have very flexy wings and the gears are attached to the wings that can cause issues. I often mount the gears to the fuselage and then use the offset tool to make them look like their attached to the wing to get around that.

Basically any asymmetry will cause a pull to one side.

[Leafbaron]

I have had the same issue with every plane and spaceplane I've ever made except they pull to the left, only slighly. If i were to leave it unchecked and carry all the way to the end of the runway before lifting off it would aim me square at the light on the end of the run way. very small pull over 2.5km 

[A_name]

Most planes in KSP drift slightly to one side or the other during takeoff. There's been ample discussion on this for ages but I can't recall now what the cause is. That said, you can mitigate the effect as others have said by using (auto)struts and making sure your gear is large enough to support your weight and is properly aligned in on all axis.

[Yakuzi]

Reduce the friction of the front wheel to 0.1 units (advanced tweakables) and you should be sweet.

[Daniel Prates]

13 hours ago, A_name said:

Most planes in KSP drift slightly to one side or the other during takeoff. There's been ample discussion on this for ages but I can't recall now what the cause is. That said, you can mitigate the effect as others have said by using (auto)struts and making sure your gear is large enough to support your weight and is properly aligned in on all axis.

There has indeed been countless discussions ... there was even a version of the game (1.1.3 ?) that claimed to adress this problem ...and as far as I know there hasn't been any proper solution. They will sometimes do that.

However....

I have found that there are ways to reduce the effect of planes drifting to the side during takeoff. This is what I usually do: 

1. Put the main landing gear further apart, or if possible, increase the size/number of gears. Too much weight for small gears cause problems, drift included.

2. Watch for the center of thrust. If the line of thrust goes ABOVE the CoM, that generates a nose-down torque that forces your craft against the runway. That force unbalances your craft.  Having your CoT pass through the CoM is a good design carachteristic for several reasons and this is one.

3. Check your control surfaces (with RCS aid if posisble). They too can be generating nose-down torque.

4. Some wheel mods allow you to configure wheel steering and wheel motors. Disable them,the stering at least on the main gears, and the motor in all of them.

 

[Tex_NL]

Somethings I wonder why I even bother.

On 9-12-2015 at 10:44 PM, Tex_NL said:

Q: My plane violently veers off the runway. Why?
A₁: Your landing gear is misaligned. Make sure you don't have any toe-in or toe-out. Even a tiny, invisible misalignment can cause this problem. It can happen due to the curved shape of the part you're attaching the landing gear to. One way to fix this in the SPH is to select the rotator widget ("3" key), turn on absolute snap ("F" key), then wiggle the landing gear one notch out and back to parallel. This guarantees perfect alignment.
A₂: You are wheelbarrowing. Too much lift too far behind the centre of mass (CoM). The tail of your plane is lifted off the ground before the nose and it starts to fall over making it steer either left or right.
A₃: Your connections are too weak. Connections between parts are always a bit flexible. Use (auto)struts to shore them up.

 

[adsii1970]

1 hour ago, Tex_NL said:

Somethings I wonder why I even bother.

[Edited by adsii1970 - removed link and link preview]

Because we both share the same trait. You want to help others get enjoyment out of the game and you use the philosophy of "I wrote this whole thing to help others..." ad become frustrated when others would rather start new threads than to simply search to find what is already out there...

[Numerlor]

3 hours ago, Tex_NL said:

Somethings I wonder why I even bother.

 

Because you used words that I wouldn't even think of while searching for question, and also you mention violently and I don't think that when I stay on the runway whole time it is vilolently

Edited February 16, 2017 by Numerlor

[Tex_NL]

3 minutes ago, adsii1970 said:

Because we both share the same trait. You want to help others get enjoyment out of the game and you use the philosophy of "I wrote this whole thing to help others..." ad become frustrated when others would rather start new threads than to simply search to find what is already out there...

Indeed.
I estimate 99 out of 100 KSP related questions have already been answered. (The same goes for suggestions by the way.) But still people assume their situation/idea is original or unique and start a new thread without even bothering to search. And, nothing personal to the OP, it's ALWAYS a new guy.

[klesh]

9 hours ago, Tex_NL said:

Indeed.
I estimate 99 out of 100 KSP related questions have already been answered. (The same goes for suggestions by the way.) But still people assume their situation/idea is original or unique and start a new thread without even bothering to search. And, nothing personal to the OP, it's ALWAYS a new guy.

 

So get used to it?  I've never seen someone more abrasively helpful.

 

The only words he could've searched to be brought to your post is "violent" and "veer".   "Runway" would've been buried in results.  You should cut "new guys" some slack.  Sheesh.

[Cunjo Carl]

Had this problem with quite a few rockets over the years. I found one thing that helped was swapping out the main pod (which always happened to be the root part). Just replacing it with an identical copy would help (or would at least pick a new direction. ) Edit: Given it's a bug, I suppose it pays to be more specific. 1. Remove things from root-part-pod. 2. Delete said pod. 3. Put in a new one. 4. Reattach.

A much more mundane possibility, if you ever rotate a part (like your tailfin) without having snap on, it can be nearly impossible to get it precisely realigned without using the uncommon space bar to reset its rotation. Finally, if your wheels are attached to an uneven surface they can occasionally pick up a bit of skew. The easiest way to see this is to select the part in rotate mode and press 'f' to swap quickly between relative and absolute. It'll make sense when you do it. Just get the two modes aligned. There used to be a button to do this automatically, but I think it got depricated.

In any case, Good luck with your SSTOs, @Numerlor!

Edited February 17, 2017 by Cunjo Carl

[Daniel Prates]

On 16/02/2017 at 1:17 PM, Tex_NL said:

Somethings I wonder why I even bother.

 

 

15 hours ago, klesh said:

 

So get used to it?  I've never seen someone more abrasively helpful.

 

The only words he could've searched to be brought to your post is "violent" and "veer".   "Runway" would've been buried in results.  You should cut "new guys" some slack.  Sheesh.

I must say, @Tex_NL, if you got reactive responses like the one you gave him, at the time you were a new member yourself, you probably would not only got angry by the community's agressiveness, but your own development as a member would have probably been curtailed. Maybe you would have left altogether - preventing you from becoming the game and forum undisputed savant you did become. 

But have you? Having posted something before makes your own input or info the last word on any given subject? Can't there be more to be said on a topic? Do you know all there is to know about a subject, to an extent that a post you already posted in some other obscure thread is the absolute ammount of collected knowledge there is to be known?

Reading your answer to the proposed drift discussion, I see that you are oblivious to at least a few things. I can think of at least a few: a) it is not only the CoL that needs balancing, the Center of Thrust creates the same results, because of the same factors. It is advisable to make your CoT to pass thorugh your CoM; b) wheel input from wheels that generate steering/power can interfere too, it is advisable to disable them during take-off at least; c) since we're at it, all vectors caused by all parts able to create input (not only the landing gears) can create drift, as the stability enhancer uses all parts at the same time, unless you deactivate some; d) it usually pays off to set dedicated control surfaces for yaw, roll and pitch. If you forget to do that, different pair of surfaces may be attempting to control the same axis and that is also a cause for unbalance.

And there are other factors, none of which were encompassed in your quoted post, which apparently you presume to put an end to all discussions on the matter. So maybe @Numerlor was entitled to pose a honest question and get an honest response - even if it simply redirects him to another clearifying thread.

I have something close to 900 hours of KSP, registered on steam alone, which makes me  something past an ignorant on KSP.  Still, in one of my very first posts in this forum, just a few weeks ago, I got a rash response by a member on what I considered a valid question, as if old members have reached some game "illumination" status. Thats not cool!  so I am giving @Numerlor a like on his thread, in the hope that this does not disencourage him from being an active member, as I am sure has happened to other people before.

 

Edited February 17, 2017 by Daniel Prates