The REAL Reason Our Planes Veer Off the Runway

[Xooxer]

The T1 runway is the only runway. The "upgraded" runways are only a graphic effect. They have NO COLLISION. What we are driving on is the same old crappy gravel with the pot holes and little hills, not the smooth flat paved surface we are presented with.

Your landing gear is dipping into and over these very large imperfections in the T1 gravel runway, hidden under the paved runway model. That's why it suddenly goes one way or another, and why it seems to go randomly left or right.

 

Temporary workaround until this is fixed: Use the flat ground left of the runway. It's ACTUALLY flat, and will not make your plane suddenly steer left or right on it's own.

 

Don't believe me? Build a little lander probe with landing gear and launch it on the runway. Watch it sink into the runway model and settle on uneven terrain below. Good luck!

[Red Iron Crown]

You sure about that? The top tier runway seems awfully smooth to me, as smooth as the surrounding terrain.

[katateochi]

I find the T1 runway to be monstrously hard to take off from or land on at high speed, whereas I don't have any problem with the other two.  So I'm not sure what you're getting at here OP.
Aircraft veering off is usually down to the craft's design, a perfectly symmetrical craft will go straight down the T2 and T3.

[Overland]

Not sure about the bumps but I know the tiny pinpoint threshold lights are a "thing" having actual physical presence.. Although only towards the end of the runway in the middle. A group of 3 they are.. 

 

Ive lost many 6 to 8 car trains with 1 ton wheels.. Long enough for a wagon to be sitting on one upon launch.. The wheel will fully contract its suspension as it goes over.. Happening for most of the trailing wagons too like an invisible speedhump..

Itll then spring back onto the runway after its freed where the impact will trigger the runway destruction

 

Always wondered if planes ever hit it too?

[Gaarst]

2 minutes ago, katateochi said:

I find the T1 runway to be monstrously hard to take off from or land on at high speed, whereas I don't have any problem with the other two.  So I'm not sure what you're getting at here OP.
Aircraft veering off is usually down to the craft's design, a perfectly symmetrical craft will go straight down the T2 and T3.

Having used the T3 runway (sandbox) a lot for speed tests, I can assure you that it is smooth, but even the most symmetrical craft will want to get off the center at high speed (this can be quite dramatic when over Mach 1).

But I think the veering off is due to the wheels mechanics and aerodynamics.
If I had to guess a cause I'd say floating point operations precision limitations (same thing as for wobbly orbits): for something relying a lot on symmetry like a plane or something going very fast, the slightest change in lift or grip can move it, and as you go off prograde, the sideways force will get stronger.
This or the wheels mechanics being wonky. This is a good thing because it is supposed to change in 1.1, with a chance for this to disappear.

And also, FYI, the runway is smoother than the ground around it. It is so smooth that it is actually flatter than Kerbin, which is why your planes accelerate towards the centre if you leave them at one edge without brakes.

[moogoob]

5 minutes ago, Gaarst said:

And also, FYI, the runway is smoother than the ground around it. It is so smooth that it is actually flatter than Kerbin, which is why your planes accelerate towards the centre if you leave them at one edge without brakes.

Damn, that's cool! What a drastic difference that 10x size modifier over real-life scale makes.

[Temstar]

One other reason is lift behind CoM. So we all know that for inherit stable plane you need CoL behind CoM. Unfortunately that means when you accelerate down the runway on your tricycle landing gear the first bit of lift your wings generate lighten the load on your main gears and in effect shift almost all of the unsupported weight of the plane to the single front landing gear. This turns the plane into something like one of those single wheel wheelbarrows and those are known to snake all over the place when not controlled well.

Conventional landing gear (two big wheels in front, one taildragger behind) will not have this problem.

[Majorjim!]

50 minutes ago, Gaarst said:

Having used the T3 runway (sandbox) a lot for speed tests, I can assure you that it is smooth, but even the most symmetrical craft will want to get off the center at high speed (this can be quite dramatic when over Mach 1).

But I think the veering off is due to the wheels mechanics and aerodynamics.
If I had to guess a cause I'd say floating point operations precision limitations (same thing as for wobbly orbits): for something relying a lot on symmetry like a plane or something going very fast, the slightest change in lift or grip can move it, and as you go off prograde, the sideways force will get stronger.
This or the wheels mechanics being wonky. This is a good thing because it is supposed to change in 1.1, with a chance for this to disappear.

And also, FYI, the runway is smoother than the ground around it. It is so smooth that it is actually flatter than Kerbin, which is why your planes accelerate towards the centre if you leave them at one edge without brakes.

Yeah they said in the newest dev notes or the stream thing that the wobble is due to the current wheel physics. It is fixed with the new wheels physics.

Edited February 3, 2016 by Majorjim

[kurja]

Also, planes veering on the runway was a thing before different tiers of runways existed.

It really is awkward that the ground next to the lowest tier runway is smoother than the runway  

[RizzoTheRat]

See, I knew there was a reason I always land on the grass not on the runway

[Washell]

5 hours ago, RizzoTheRat said:

See, I knew there was a reason I always land on the grass not on the runway

Plenty of small town airfields in the real world where the grass strip is smoother than the tarmac one.

[Evanitis]

While I feel with the op, I can't agree. The T1 runway is indeed the bumpiest surface in the whole universe. The T2 is totally manageable, while the last one is as flat as any grassy surface if not more.

Anything else is just sloppy design.

[luizopiloto]

The real reason is... the runway actually points to HDG 91, and the craft starts pointing to HDG 90... if the wheels are not perfectly aligned, any adjustment you do during takeoff will cause instability...

[Jhawk1099]

18 hours ago, Red Iron Crown said:

You sure about that? The top tier runway seems awfully smooth to me, as smooth as the surrounding terrain.

Yeah I have had plenty o' craft go off of the tier 3 runway but only like 2 off the t1. Perhaps confirmation bias?

[kstark]

I found that basic aicraft tail makes all the trouble with instability during hi speed taxi runs. Now I build my designs without it (for example with structural fuselage and aerodynamic cone to close the hole) and these ones are perfectly stable during takeoff!

[Dfthu]

I think I heard somewhere that the reason it goes off the runway that maybe there's to much weight on the wheel and it bends. May not be right though.

 

EDIT Found it! http://forum.kerbalspaceprogram.com/index.php?/topic/47818-basic-aircraft-design-explained-simply-with-pictures/&page=1

Edited February 3, 2016 by Dfthu

[Majorjim!]

57 minutes ago, Dfthu said:

I think I heard somewhere that the reason it goes off the runway that maybe there's to much weight on the wheel and it bends. May not be right though.

 

EDIT Found it! http://forum.kerbalspaceprogram.com/index.php?/topic/47818-basic-aircraft-design-explained-simply-with-pictures/&page=1

LOL everyone ignored my response above. Thanks for the confirmation link though.

[bewing]

I agree with Rizzo -- to heck with the runway; I don't care what its basic mechanics are. The only reason to upgrade it is to have bigger planes. The grass allows you to land or take off in any direction you please. A perfectly nice 3 Km runway in every direction. 6 Km if you come in from the right direction(s).