SAS Turns Off With Each Stage Seperation?

[shadragon]

Had a few maneuvering issues until I figured out SAS stabilization. (I'm in early stages of career mode and have no RCS yet) However, SAS when on, seems to turn off every time I decouple a stage, which has resulted in some rather deep craters near the launch center. 

I'm getting around this by re-engaging SAS with each separation, but I still forget on occasion and either lose control or have the craft go off course enough to have to reset back to the pad.

Am I missing something obvious in settings to keep this on? Suggestions welcome.  

Edited August 31, 2016 by shadragon

[Sonny_Jim]

Do you mean SAS?  Normal behaviour is for SAS to remain engaged during stage sep.  Do you have any mods installed?

[shadragon]

Yes, SAS, sorry. I amended the original question. No mods and brand new install. 

[Sonny_Jim]

Odd, do you have multiple probe cores? 

[shadragon]

I'm still doing early career mode. Simple two stage sub-orbital rockets with a MK I pod, thermometer, science jr., mystery goo and that's about it. 

PS. Just looked up probe cores. No, I'm not doing those yet. 

[Sonny_Jim]

Could you post your save file somewhere with a craft ready to go on the launch pad?  I'll give it a whirl to see if the SAS turns off during stage sep.

[shadragon]

Sure, but will not be for a few hours, at least. Thanks. 

[Aegolius13]

Have you been using action groups?  Maybe you accidentally had an SAS related command on the "stage" action group?  Seems very unlikely though, especially if you're in early career...

Also maybe check your keyboard bindings.  Maybe the spacebar also got assigned to SAS?

You could also try to build a new ship and see if the same thing happens.  That would help narrow down whether this is a global or craft specific problem.

[shadragon]

SAS is set to T. I don't think I've changed any hotkeys from default. No action groups set by me. 

This happened on multiple builds, but I'm sure to make some from scratch. Will include any build save games I have issues with. 

[CaLVin-K]

I've noticed this happens when the root part of the ship is in a different stage from the control point and the root part is jettisoned. AFIK it happens every time, thats why I build my ship and then re root to the whichever control point I deem most important. 

 

 

[Mikki]

5 minutes ago, CaLVin-K said:

I've noticed this happens when the root part of the ship is in a different stage from the control point and the root part is jettisoned. AFIK it happens every time, thats why I build my ship and then re root to the whichever control point I deem most important. 

Exactly. My KEMAZ mobile launcher in the spacecraft exchange has this sickness aswell. 

[shadragon]

Here's a ship. Second and third stages trip SAS off. 

http://kerbalx.com/shadragon/Science-Mk-I.craft

Edited August 31, 2016 by shadragon

[shadragon]

19 hours ago, CaLVin-K said:

I've noticed this happens when the root part of the ship is in a different stage from the control point and the root part is jettisoned. AFIK it happens every time, thats why I build my ship and then re root to the whichever control point I deem most important. 

OK, so... 

Wiki - "The root part is the first part placed in the VAB or SPH so it's on the top of the dependency tree."

SAS Wiki Page - "The PID control is applied to the vessel's rotational velocity at the command point. This means that large rockets that tend to wobble out of control during flight do so because the SAS sees the tip (where the command module usually is) rotating and assumes the entire vessel is spinning this fast. For this reason, "wobble" can be largely eliminated by controlling the vessel as close to the CG as possible. This can be accomplished by placing a command module or docking port in the middle of the rocket. Right click the unit and select "Control From Here" to change the control point. If you end up controlling the "dead" end of the rocket after stage separation, simply press the "[" or "]" keys to select the appropriate section."

From the above, I take it that the control point is the command pod and the root part is stage #1. Your solution is to reroot to the control point you want, but I only have one. Does reselecting my command pod fix this?

Cheers. 

[Sonny_Jim]

In the editor, press '4' then select the top most command module.

[CaLVin-K]

On September 1, 2016 at 9:58 AM, shadragon said:

OK, so... 

Wiki - "The root part is the first part placed in the VAB or SPH so it's on the top of the dependency tree."

SAS Wiki Page - "The PID control is applied to the vessel's rotational velocity at the command point. This means that large rockets that tend to wobble out of control during flight do so because the SAS sees the tip (where the command module usually is) rotating and assumes the entire vessel is spinning this fast. For this reason, "wobble" can be largely eliminated by controlling the vessel as close to the CG as possible. This can be accomplished by placing a command module or docking port in the middle of the rocket. Right click the unit and select "Control From Here" to change the control point. If you end up controlling the "dead" end of the rocket after stage separation, simply press the "[" or "]" keys to select the appropriate section."

From the above, I take it that the control point is the command pod and the root part is stage #1. Your solution is to reroot to the control point you want, but I only have one. Does reselecting my command pod fix this?

Cheers. 

the re root function in the VAB allows you to change the root part of the vessel to whichever part you want it to be (with a few restrictions, i think the part must not be physics less) so yes I utilize this function to change the root part to my command pod.

 

Edited September 2, 2016 by CaLVin-K