[Grandpa Kim]

From the Newbie FAQ

7.2.19 Q: How do I set up my fleet to capture a planet:
A(Geoshmo): a. Make sure the troop transport has a ship strategy of capture planet.
b. Make sure the fleet has a strategy of capture planet.
c. Make sure the troop transport has troops onboard.
d. The target planet must have a population greater than 0. For some reason, the troop transport won't attempt to capture an enemy planet with 0 population.
As long as you do these four things then your fleet will attempt to capture the enemy planet. If the enemy has weapons platforms the attack ships will engage it till the weapons plats are gone or your ships are. The troop transport will run for the corner while this happens. Once the platforms are gone the troop transport will make for the planet. Your attack ships will then concentrate on taking out any ships/bases/fighter/sats/drones left. The troops will drop if your transport can get there before the combat round is over. If your troops are defeated your fleet will then turn back and attempt to glass the planet. If your troops are successful and the enemy has any bases or sats left they will open fire on the planet. Sometimes, not too often in the unmodded game, the combat round will end with your troops and the enemy at a stalemate. If this happens combat will resume during your opponents next turn. If it Lasts long enough to get back to your turn you can even try dropping reinforcements on the planet. In the unmodded game though this rarely happens.
7.2.20 Q: When you defend a planet this time, are mines, fighters and satellites stored in the planet cargo automatically launched to join the combat, or are they given to the enemy?
A(Arkcon): Units in storage of a captured planet or ship become yours. You can never capture units in space.
7.2.21 What if you have all troop transports and no attack ships? Will they try to take the planet anyway, even if there are weapons platforms? Sometimes I want to send in a heavily shielded/ armored transport to take the weapons platforms intact.
A(Geoschmo):Yes, if there are only troop transports and no attack ships they will rush the planet straight away. The same occurs if during combat all your attack ships get destroyed or disabled. Your troop ship(s) will rush the planet, even if there are still active weapons platforms left defending it.
7.2.22 Q: Which units will a planet automatically launch during combat?
A: Fighters & Drones only. Weapon Platforms and Troops cannot be launched obviously. Satellites and Mines are NOT automatically launched.
7.2.23 Race's characteristic - physical strength do affect troops but not militia. (Foreman)
7.2.24 Bear in mind weapons on a troop transport will not fire, even when in range. Unless you change the strategy [from "Capture Planet"], and then they won't drop troops. Point defense is ok though I believe. Will help if the planet is shooting missles at you. (Geoschmo)
7.2.25 I'm sure most of you know this, but in Tactical, if the multiple planets are adjacent to each other (sometimes they aren't and there's a row of empty sectors between them), you can drop troops on one planet, conquer it, then select the conquered planet and order it to drop troops on an adjacent planet. (Erax)

I can confirm this info is deadly accurate with the following provisos:

I have successfully captured planets where the troop ship was set to capture planet but the fleet was NOT!

I have successfully captured planets with unconnected Groups of fleets/ships with only the troop ship set to capture planets!

BUT... being a suspenders and belt man, I do not make a habit of this. I may have just been lucky but it has worked and the combat replay looked just like a properly ordered capture planet fleet.