"cannot pick up ground unit because of insufficient space" + military protection

[M_J_M (OP)]

I try to load a Ground Unit into my troop transport but i permanently get the message "cannot pick up ground unit as the ship has insufficient space", including a time stop.     My ship has a troop capacity of 2 battalions, so i should be able to load them.  Did i miss something?

The reason why it want to move my troops is because my colonies start to get political unrest: "unrest is rising because the population on Luna believes that the central government is not providing sufficient military protection".  Do i need ground units or space ships or do both suppress the unrest? My search in the forum and wiki was not 100% conclusive.   

[Nightstar]

Some ground units are larger than a battalion in size.  Notably construction and low tech stuff.  What are you trying to load?

What your citizens want is PPV -- Planetary Protection Value.  This is provided by military ships and PDCs.  I think that while troops don't provide any PPV, you can use troops to suppress population unrest, but I'm not entirely sure.

[M_J_M (OP)]

Ok, i just saw in the ground unit training tab that a low tech unit has a size of 50, but other units a size of 5.    Actually i thougt if there were any differenzes in size the high tech unit would be bigger, because of more equipment and so on. . .  Anyway, Troops, except cadres (what are they supposed to do?), do surpress unrest. 

[MagusXIX]

Cadres are used as a sort of training pool.  You can convert a ground unit into a cadre if you want to get rid of that unit and use it to train something else much more quickly.

[ddblackhawk]

Low Tech units represent Divisions, which, using Trans-Newtonian units are up to 4 Brigades.   Brigades have up to 4 Battalions, while Battalions have a size of 5.   I suppose Low Tech Divisions are meant to represent 2 Brigades?

Cadres are what you get when you want to upgrade Low Tech Divisions to Trans-Newtonian Battalions.

Step 1: Have a Low Tech Division
Step 2: Click the Conv Cadre button in the Ground Units tab.
Step 3 In the GU Training tab select the Battalion you want to train while making sure the Use Cadre tick box is selected.

If you start from a Conventional Start then you would use this to convert your rather useless Low Tech Divisions into something useful.   By using Cadres you train a new Battalion faster, I think it's cheaper to use Cadres as well, that is, if you already have the Low Tech Divisions.

ddblackhawk.