leaping launch stabilizers

[steuben]

I'm not sure what I'm seeing here.

I launch the ship. it flies up no problem. at about 6000 metres the launch stabilizers seem to reach up and grab my craft and prompt rip off bits.

I change the order of the items within the stage so that the engines are altogether and the stabilizers are all together and it works no problem... well no problems that aren't related to 3.5kt ground weight of craft and failures of design.

for the most part the order of items within the stage shouldn't make a difference, correct?

so known bug/issue? weirdness with my design? kraken tentacles?

ANSWER:

1. use a patch

2. use a lossable peice like a separator

Edited September 4, 2015 by steuben

[LN400]

It's a known bug but I'm not sure if the cause is known. I haven't found any solutions other than making the stabilizers as short as possible. They will still appear somewhat randomly but at least they won't crash into the ship. Do you hear any sound glitches as well at the same altitude?

[FyunchClick]

Hehe. I've also seen them show up as debris in orbit once or twice in the mission control window, but never reaching up to rip off bits.

[Gaarst]

Fix available here.

[TheMoonRover]

I'm not sure what I'm seeing here.

I launch the ship. it flies up no problem. at about 6000 metres the launch stabilizers seem to reach up and grab my craft and prompt rip off bits.

I change the order of the items within the stage so that the engines are altogether and the stabilizers are all together and it works no problem... well no problems that aren't related to 3.5kt ground weight of craft and failures of design.

for the most part the order of items within the stage shouldn't make a difference, correct?

so known bug/issue? weirdness with my design? kraken tentacles?

Did you say 3.5 KILOTONS?!?

If you do mean 3500t, that's probably contributing. Launch stabilisers not always staying put is a known bug, and in my experience it happens more often with either a high part count, a high mass ship, or if there is a moment of insanely high acceleration. In other words, it happens more often if you're making the game work hard in some way. The order of items within a stage shouldn't have any effect, although I wouldn't be surprised if it does when the game is severely lagging. I've never heard of launch clamps actually striking the ship though except on launch.

And powerful enough ships have been known to rip launch clamps right out of the ground, often damaging the ship in the process.

[Hagen von Tronje]

It has nothing to do with either rocket size or stabilizer length, but placing stabilizers outside the launch pad zone. Any stabilizer outside the circle in VAB will probably be subject to this. It tends to show up more on gigantic rockets because they naturally fill up the pad.

For huge rockets, make a level bottom on the first stage and ditch the clamps. 3.5kt is perfectly reasonable and don't let anyone tell you otherwise.

[Gaarst]

Topic debated here. Solution found, cf my previous post.

[LordFerret]

Fix available here.

Topic debated here. Solution found, cf my previous post.

Agree. ^

[FungusForge]

Another fix here that just deletes the clamps after takeoff.

[steuben]

Did you say 3.5 KILOTONS?!?

yes 1.21 jigawatts... er 3.5 kilotons. for a mere 240 ton load. at least in testing.

i can't lay the bottom flat on the pad unfortunate. the ship is a puller design for my station modules.

i'm going to try claw's bug fix module, and the clamp to decoplers.

dang i was kind of hoping for kraken tentacles.

[RocketBlam]

yes 1.21 jigawatts... er 3.5 kilotons. for a mere 240 ton load. at least in testing.

i can't lay the bottom flat on the pad unfortunate. the ship is a puller design for my station modules.

i'm going to try claw's bug fix module, and the clamp to decoplers.

dang i was kind of hoping for kraken tentacles.

I'm curious to see this monstrosity.

[steuben]

tried it with radial separators between the clamps and the ship. which looks like it worked... or it could have just been replacing the clamps. I ain't gonna argue if either one worked. it launches in a disconcerting cloud of fire, debris and smoke though.

so I'm not going to worry about claw's patch atm.

i'll get some screenshots up when I get home. there's no elegance to the design, just 5+kps of delta v. but she she'll get that 240+ tons to a 1 million x 1million orbit in two steps. a messy circularize at 100km and than a raise and circ to 1,000km

[KrazyKrl]

I have a weird feeling that some PhysX value is overflowing that causes the launch clamps to act like that. (Infinite break force, with excessive load multiplied by leverage.) And I don't think KSP has a few simple sanity checks to prevent launch clamp weirdness.

Honestly, I'd be fine with excessive crafts being able to rip launch clamps from the ground. The only problem comes if they are in-flight; and they rip off pieces because the game assumes they will always be connected to the ground.

[Claw]

I have a weird feeling that some PhysX value is overflowing that causes the launch clamps to act like that. (Infinite break force, with excessive load multiplied by leverage.) And I don't think KSP has a few simple sanity checks to prevent launch clamp weirdness.

It's actually because there are situations where the clamp ends up thinking it is in flight, and doesn't get packed properly. Failed packing resets it back to it's relative position near the craft in flight and ensuing collisions, which is probably why the decouplers work. It's not exactly that it thinks the clamp is connected. It's just returning it to the vicinity, which usually results in a collision. And no, KSP assumes the launch clamp can't leave the ground, which is why there are no later checks.

Cheers,

-Claw

[MarvinKitFox]

.... 3.5kt is perfectly reasonable and don't let anyone tell you otherwise.

In the good old days (~.23) I lobbed an even 43Kt in one launch. It actually got to orbit, at a speed of more than 8 seconds per frame.

[steuben]

since it was requested.

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the first 6 show her in a very scary lift off with 320 tonnes of test mass.

last is design 3 meeting up with design 1 at 10,000 km orbit. about 85 metres apart.