Kerbal Space Program

This seems to always happen with larger crafts on landing gear. It seems when the game is loaded, for the very first few frames, the wheels will clip into the ground and thus create the bounce.
Hopefully the extra bit of info helps...

https://www.youtube.com/watch?v=yCpDecrqiLA&t=19s

In case of the LY-35 Medium Landing Gear:

I suspect there are 3 'objects' at play.

1. There is an object that determines where the wheel should be in contact with the ground
2. There is the collider.
3. There is the visual part we can see.

What I believe is going on in relation to it being on a Flat surface (more seems to be happening when wheels are on the hills):
1. LY-35 appears to load into the correct position above the ground initially.
2. LY-35 then drops into the ground to the approximate position of the collider object (2) INSTEAD of the object that determines the position of the wheel on the ground (1)
3. Then the suspension realises its compressed according to where the object that determines to the position of the wheel (1) in relation to the collider (2) and propels the craft into the air.

This is happening to me whenever I timewarp with medium landing gears. For some reason, it only happens if all my gears are extended. If I only retract the front landing gear, or only the back, or I have none extended at all (in other words, if part of the plane's body is touching the ground) this does not happen.

More examples, again medium and XL landing gear are worse offenders:

https://www.youtube.com/watch?v=X0t6HetzihQ

#16159 is a duplicate of this issue.

bubbagump wrote:

Please consider raising the priority of this bug to critical. It's making large parts of the game unplayable e.g. refuelling on moons, base construction.

I'm trying to understand why this issue has not been hotfixed already.

I'm a senior software engineer and this is one of those bugs that requires an immediate solution, stopping other work until is fixed.

jrodriguez wrote:

bubbagump wrote:

Please consider raising the priority of this bug to critical. It's making large parts of the game unplayable e.g. refuelling on moons, base construction.

I'm trying to understand why this issue has not been hotfixed already.

I'm a senior software engineer and this is one of those bugs that requires an immediate solution, stopping other work until is fixed.

I concur. This is outright game-breaking.

I can confirm that this issue is ship specific. I had two ships landed on Pol within 450m of each other. After time warp, only one bounced and exploded. Ships have different components though I am unable to determine which component or parts that contribute to the bounce. Using mods KAS 0.6.3, KIS 1.7 and Docking port alignment 6.7.0

Update to this. I was able to get the ships within 80m of each other. Now the bounce and explosion does not happen! Doesn't seem to be any consistency to it.

There definitely seems to be some issues with physics. Beside the ship jump as described above, I noticed issues on EVA. Kerbal was carrying a container. Mobility changed accordingly with added mass of container, but when the container was no longer part of kerbal's inventory, her mobility became erratic, including violent uncontrolled spin. I was able to stop the spin by shutting off RCS and then turning it on again, but not consistently.

Secondly, container on the back of the kerbal seems to be an apparition, not a solid, as it passes through ship components while on the kerbal's back. As soon as the container was no longer in the inventory, it interacted normally with other solids. Quantum container?

I am having this problem with a lander on Bop - my design is based on spending a few days on the surface to refuel before moving on. Every time I switch away from the lander and switch back, or go to time warp and then come out, the lander bounces off the surface. I can land it again and continue, but it's annoying.

The total mass of the lander is 91,707 kg and is sitting on four LT-2 struts. All stock parts. I'm on a hill at about a 15 degree angle from vertical, according to the navball.

Mod list: Kerbal Alarm Clock 3.8.5.0, Kerbal Engineer Redux 1.1.3.0, Kerbal Joint Reinforcement 3.3.3, KSP AVC 1.1.6.2, Navball Docking Alignment Indicator CE-2 1.0.3, TAC Fuel Balancer 2.14, TriggerAu Flags 2.9.2.0.

Help me, Obi-wan Kerman.

As a short term solution i resolved this issue by editing the config file for the LT-2 Landing Struts, the ones that gave me the most bounce on load issues. I changed damperRatio = 1 to damperRatio = 10 and this caused the strut to spring back quicker which solved the problem. Maybe the force of the bounce is relating to the length of time the part is clipped? Might be why the problem is more pronounced on heavier ships.

G:\Steam\steamapps\Common\Kerbal Space Program\GameData\Squad\Parts\Utility\landingLegLT-2

Relevant lines:

targetPosition = 1.0                  <-- not sure            
        springRatio = 6                   <-- when set to 0 the strut sags to the ground, I think a high number would make them ridgid(maybe they would break on                                                                       landing)
        damperRatio = 10              <-- at 0 the bounce never ends, at 10 it stabilizes quickly with minimal bounce
        boostRatio = 0.6                 <-- not sure     

Another weird bounce situation. Landed ship on Minmus within 1.5 km of kerbonaut to be rescued. Kerbonaut uses jetpack to reach ship. When kerbonaut is about 300 m away the rescue ship bounces off moon falls back and destructs.

Note: the ship had a stable landing and I used bracket keys < [,] > to switch to kerbonaut.

unclejace wrote:

Another weird bounce situation. Landed ship on Minmus within 1.5 km of kerbonaut to be rescued. Kerbonaut uses jetpack to reach ship. When kerbonaut is about 300 m away the rescue ship bounces off moon falls back and destructs.

Note: the ship had a stable landing and I used bracket keys < [,] > to switch to kerbonaut.

YUP! I've seen the exact same thing.

This just happenned to me for the second time. First time was on a rescue mission, with the rescue ship leaping from the ground as the rescuee approached. This latest time was even more frustrating - a mining mission on Gilly. I built a harvesting lander that could also be used to supply ore to a refuelling station in orbit, and left it drilling for the mission's 3000 units while I did some other missions. When I switch back to the lander after a few Kerbal weeks, it jumps into the air and breaks up. This has only happenned to me in 1.3.1. Please fix it!

Edit: One point occurred when reading other posts. On the rescue mission, if I could land my rescue ship close to my Kerbal (within 100 metres), the problem didn't occur. My mining lander remains unuseable, though, even if I fiddle with the landingLegLT-2.cfg file as someone suggested.

This is still happening on 1.3.1.1891

Landed craft bounce on loading and usually blow up or flip over and are damaged. Game is unplayable like this - haven't been able to play since this started in October.

Open since 10/8, critical priority and 0% done. WTF - I guess I'll check back again in a month.

midgetsl4yer wrote:

Has anybody tried disabling all mods? Is this a vanilla issue?

Yes, it is happening without any mods.

I cannot believe that they have not addressed this. The game is completely unplayable. Jeb has been stranded on the Mun for over three months... his rescue craft flips over and explodes when I switch back to the ship.

Valentina currently on permanent vacation to Laythe for me.

The fact that they haven't even acknowledged the existence of this pug yet is almost amazing.

It's a miracle, progress has been made!

A comment from a dev would be appreciated.

Edit:

=================================== v1.4.0 ============================================================
+++ Bugfixes
Improve vessel Jumping/positioning coming off rails.

We shall see...

I need to do some more testing, but the problem has been significantly reduced even on hills.
Not sure if I can say its resolved, but its way closer to fixed that it was

GOG 1.4.1
Steam 1.4.1 MH

Works in both 1.4.1 and MH

This issue is definitely not fixed. It still happens in 1.4.5.2243. See Bug #16159.