Alright, so my group is pretty motley and extremely hungry for action and adventure. They have recently acquired a base of operations at a secluded space station, where they uprooted a corrupt security captain and have become employed by a politician seeking to take hold of the station's leadership positions. My next session is going to be a wild chase after a spy that is leaking information out to an incoming pirate/slaving crew. The party will be tasked with finding the mole and exposing him or eliminating them. This will be followed with the new security captain that they have put into power asking their assistance.

The captain will request their aid in ramping up fortification and defensive measures against an attack. This will require things such as the mechanic fixing up shield generators and turret systems. The pilots getting a couple of fighters ready and the muscles of the group "recruiting" some help from people around the station. The session will come to a climatic battle when the pirate/slaving fleet exits hyperspace in the immediate vicinity of the station. I am looking at guiding it into a manner that some of the PC's stay on the station operating the defensive systems they installed and repaired, as well as combating any enemies that manage to board onto the station. Other PC's will be given options to get in their party's ship or some fighters on the station in order to take the fight to the enemy fleet and possibly board their command ship.

Any pointers on how to task such a daunting space combat scenario? Or suggestions on ships and systems to use? I am working on drafting up some nemeses and adversarial NPC's as well as skill checks. I.e. the mechanic will make computers checks to use the turret system and combat enemy ships. Pilots will make a very difficult piloting check to dock and board the enemy command ship. Etc. Would greatly appreciate any advice and ideas to help me mold this better.

My biggest suggestion is only focusing on the players. Let the rest of it--minor enemy ships, other defensive guns, etc--be the backdrop for the PC. Make the backdrop fully narrative to meet the needs of your story. Only roll when the PCs are involved, and maybe the way rolls play out will affect the conflict as a whole. It will save a lot of headache than worrying about the mechanics of the minutiae.

Most of the prep stuff other than the mole hunt could be pretty abstracted. Say one character uses Perception and an interaction Skill to recruit, with Successes and Failures determining the quality of the station's defenders. Another uses Mechanics to prep the fighters, a third uses Leadership to coordinate, etc.

Just so you know, Gunnery is the relevant skill to actually fire emplaced weapons, like the station's turrets. Computers could probably be used to give bonuses or penalties to another player's Gunnery, though.

For the pirates, I'd recommend older ships that really convey the "fringe" feel. A Marauder Corvette as the flagship, with Z-95s and BTL-A4 Y-Wings (the one-man version), and maybe an older YT-series freighter or two carrying boarders to seize the station (Enter the Unknown has several). The equipment should all be run-down, so for example only one or two Y-Wings would have ion cannons, and none proton torpedoes. You could even have the Z-95s be using hyperdrive sleds, demonstrating their age and ill-repair.

For the battle as a whole, as long as the characters succeed, the station should be saved, and if they fail, it falls. However, it's condition (and the future pirate threat) will depend greatly on how well they do.

I don't have any experiential advice, but in the back of my mind I'm working on a way to handle "big battles" using the narrative dice and a variety of skills. The bird's eye view is that the PCs would take leadership roles in determining the success or failure of larger groups under their control. So if you had a pilot leading a squadron of fighters, their piloting or leadership or gunnery roles would come into play determining how much "damage" is being done to the other side. If the pilot takes damage, this represents lost fighters, but of course the PC will be the last to "die".

The techie might do the same with a battery of laser cannons, coordinating fire through leadership, gunnery or computers; or they might recover damage across the base through mechanics, leadership, or even athletics.

The face might do "damage" by using deception, knowledge (warfare), leadership, or even coercion to disorient the enemy, reduce their damage output, or even negotiating their withdrawal or surrender. This can be narrated as ships fleeing or standing down, reducing the HP and damage output of the opposition as a whole.

Fighter types could lead squads of infantry using the same concept as that for pilots.

You could easily intersperse micro/character-level skill checks for specific local situations as they come up.

As a rough guide of damage and HP, I was planning to use Silhouette as both damage and soak, with S^2 as HP.

I know this is kind of spare and has little detail, at some point I hope to flesh it out. But maybe it will provide a few ideas.

How long a game session is this?

Depending how you write it, finding the mole could be a whole 4 hour session all its own. The same goes for preparing the station for the attack.

You could easily make the mole hunt and battle prep be the whole session and cliffhanger it with the pirate fleet coming out of hyperspace near the station. This would both buy you an extra few days to prep that battle... AND more importantly let you have a better idea what your players' plan of attack will be. Then you prep the battle to focus based on what their plan is and use the rest as background dressing like others have mentioned previously.

And if you have a face character in the group, make sure at the very least they are busy inspiring the station defenders in the lead-up to the battle. Certainly the station personnel will be demoralized after finding out they have been sold out to pirates by one of their own. So many face characters are underserved when GMs plan these sorts of scenarios.

Most of the prep stuff other than the mole hunt could be pretty abstracted. Say one character uses Perception and an interaction Skill to recruit, with Successes and Failures determining the quality of the station's defenders. Another uses Mechanics to prep the fighters, a third uses Leadership to coordinate, etc.

And if you have a face character in the group, make sure at the very least they are busy inspiring the station defenders in the lead-up to the battle. Certainly the station personnel will be demoralized after finding out they have been sold out to pirates by one of their own. So many face characters are underserved when GMs plan these sorts of scenarios.

Thank you both! I definitely like these ideas and how much they delve into the narrative focus. This session will probably be close to 5 hours if not more. It is starting today, so I will probably do the cliffhanger idea. The input you all provided has been awesome. I am just trying to come up with some fill-ins and it should all be good.