SAS just randomly stopped working

[Sarra]

So, basic information: Windows 10, i5 3.0 ghz CPU, 16 GB of DDR3, Geforce TI550 video card.

My install of KSP has no mods.

I am attempting to put a fuel tank into orbit using a Probodyne OKTO2 probe core. I am using an RCS system. However, the SAS is COMPLETELY useless. The buttons are available for prograde/retrograde, normal/Antinormal, and radial/antiradial, but none of them do anything. While ascending, I click the prograde hold button to turn over into an orbit, but the RCS does nothing, the rocket flies straight up. I click radial, nothing happens. If I manually steer the ship, it will act as if it's on the standard stability hold. I have put my navball into orbit mode, target mode, and surface mode, and it does not change anything. I'm in career mode and have no pilots available for this mission, and it needs to be a one way trip. I also have no other probe cores available with prograde/retrograde hold, which I need for this mission.

Am I missing something here?

[maceemiller]

I believe that SAS does not work in career mode without a pilot. Not sure but that pilot may have to be a certain "level" too.

[dangerhamster]

That core has no reaction wheel and the RCS probably doesn't have enough oomph to make a difference. If you have a reaction wheel unlocked try fitting one.

[swjr-swis]

11 hours ago, Sarra said:

I am attempting to put a fuel tank into orbit using a Probodyne OKTO2 probe core. I am using an RCS system. However, the SAS is COMPLETELY useless. The buttons are available for prograde/retrograde, normal/Antinormal, and radial/antiradial, but none of them do anything. While ascending, I click the prograde hold button to turn over into an orbit, but the RCS does nothing, the rocket flies straight up.

• Did you add a monoprop tank to your rocket? RCS nozzles by themselves will do nothing if they don't have 'RCS fuel' (monopropellant) to fire.
• Have you actually turned on RCS? 'R' is the default key for that, it will light up a green R on the top left of the navball - which is off by default. If you're not seeing the telltale white puffs from the RCS nozzles when you try to steer, they may not be working because they're off or have no monoprop to fire.
• While RCS is very good for turning a ship in space, it is very weak in the lower atmosphere. You don't state the size of your tank and main engine, but for most combinations, if your rocket is firing full throttle upwards, RCS can have a very hard time changing a straight-up course. A reaction wheel like dangerhamster mentioned, and/or a few winglets with control surfaces, are generally better choices for steering a rocket through the lowest part of the atmosphere.
• You don't mention where you placed the RCS units. If you placed the units very close to the CoM (eg. a generally encouraged configuration -for space- is a single ring of RCS units around the CoM), the RCS units will have very little leverage to turn your rocket against the mighty thrust of the main engine.
• You mention that you can click on the SAS buttons, so I am assuming lack of electric power is not the issue or those wouldn't work either. (SAS won't work without electric charge)

If none of this is applicable, explain more in detail what parts you used for your rocket, or post a screenshot. It'll help in trying to figure out what's happening.