pro/retro on SAS randomly greying out?

[putnamto]

ive noticed this a few times while building my station, when coming out of warp and trying to lock pro/retro the two buttons are greyed and i cant select them, i have plenty of EC is their something else i am missing?
oh, using the probe core after the first okto, the one that starts with an H, HECS?

[Geonovast]

Are you trying to dock when this happens?  If you have a target selected, the navball in target mode, and have less than 1 m/s of relative velocity, you won't have those options.

As always a screenshot is pretty necessary with questions like this.

[putnamto]

ill try to recreate it later.

i dont know how far i was from the target, but i was definately in target mode. 

[bewing]

Like Geonovast says -- if the reading on your velocimeter is less than 1.0 m/s, then you automatically (intentionally) lose those two SAS modes, always.

[Gargamel]

2 hours ago, Geonovast said:

If you have a target selected, the navball in target mode, and have less than 1 m/s of relative velocity, you won't have those options.

 

4 minutes ago, bewing said:

if the reading on your velocimeter is less than 1.0 m/s, then you automatically (intentionally) lose those two SAS modes, always. 

Before I even saw these answers, this as going to be my reply.  So they get my likes and votes. 

But you might be asking why, and I'll answer that as best I can before you even get to ask it.

When you are moving that slow relative to the target, it is very easy for the Prograde and retorgrade directions to change very quickly, and you'd end up with a dancing ship.  It does more harm than good to stay pointed prograde or retrograde while at these slow speed.  If you want P/R SAS, then point towards or away from the target, depending on your situation, and fire off some RCS to get you moving in the general direction.  You can then pop over to P/R and correct from there. 

 

[putnamto]

thanks guys, it all makes sense now.

 

[StrandedonEarth]

On 6/10/2018 at 7:30 PM, putnamto said:

thanks guys, it all makes sense now.

 

Imagine the scary fun people had before the fix that had the holds deactivated at low speed. Your lander is in retrograde hold slowing to a hover a few meters above the Mun and then the retrograde marker starts moving all over the navball. Retrograde and prograde switch places as the lander starts to rise. Hilarity ensues as your lander flips over to point at the ground...

[Kryxal]

I remember that, the quick-fix was to tap f to turn off SAS for a split-second when aligned for landing.  It's good that it's not needed now...

[CrashyMcCrashFace]

Also when landing in surface mode they will become unavailable if less than 1 m/s. Yes, I am that awesome because ~0.5 m/s. haha. Just kidding.