So my friends and I were making a few character ships when RT first came out (I have been meaning to post them to the ships thread, I just keep forgetting to do so. >< ) One of the ships is a Jericho Pilgrim Ship with a Jovian class II drive instead a class I. The idea behind the ship was that it had been overhauled and mated to the remains of a Sword Frigate. It gained the average between it's speed and manoeuvrability and the swords speed and manoeuvrability, boosting them to 6 and +5 respectively. In return, in addition to paying the extra hull space, I thought such an ad hoc mating would have other complications, so I lowered the armor by one to 11, and reduced Integrity by five to forty five IN ADDITION to having the larger drive cost an extra five SPs.

Now my players have seen this and thought it was a neat idea, I am debating allowing it. My question to you all is do you think my ad hoc 'costs' (armor plus hull reduction, and the whopping SP hit) is fair, and if not what would be? When I first came up with the idea I never intended for it to be used, i just thought it was neat. It seems fair to me, but I wanted a second (or third, or tenth) opinion before I said yes. This isn't really a rules question, nor is it a house rule, yet, so I put it in the main thread.

I wouldn't allow it on PC ships myself, and I doubt I'd use it on NPC designs even by fiat. Transports are always power-starved, and FFG has already given us the Lathe Pattern drives, which ought to represent about the best you can manage for merchant power systems. Installing an escort drive on a merchant gives you a lot more power, and even with big hull penalties, high SP cost, and innate lousy maneuverability, you're risking some seriously overpowered auxilliary warships or (with Wolf In Sheep's Clothing) Q-ships.

Also, if you can do it with a merchant, why not install a cruiser drive on an escort? Or a homebrew battleship drive on a cruiser? Where do you stop? Just not a can of worms I'd want to open.

The game could use a supplementary component that provides extra power, but that's something to address over on the house rules subforum.

Where does it stop? Good question. The answer would be 'Wherever the GM says'. I for one was only going to allow it for a transport (or if they were really crazy, MAYBE a destroyer). Seeing as how little they actually get out of it, the hits to armor, hull and SP cost, not to mention the larger size of the drive, are already pretty steep. They have extra power, sure, but they don't have the speed or manuverability to actually outrun anyone, nor the weapon mounts and armor to fight anyone outside of their weight class, i.e. Anything larger than another armed transport. Having crunched the numbers, the only real advantage they get out of it is the moral high ground of being able to run rings around other transports, Their weapons are slightly more powerful then they would likely be otherwise, but not overpoweringly so. All of which they could do better, and for the same SP cost, by just taking a destroyer.

I do respect your opinion, I am mostly playing devil's advocate here.

It's a good idea... from a meta-game point of view. The problem is in the heresy of it. The Adeptus Mechanicus stifles innovation, and hunts down those who do such things because of the danger. SOMETIMES if neccessity dictates, and they have a powerful enough backer, the rogue mechanicus who does such things gets away with it (See the Land Raider Crusader, for an example of such a thing happening in extreme circumstances).

Such a mixed ship would gather incredible scrutiny from the Mechanicus, and it would take hundreds of years (as in the case of the Crusader) to get it approved to be done more than once and then only if they find that the STC pattern was "always intended" to allow it to occur. It would, undoubtably, bring down more puritan Ad Mech offiicials on the crew's heads, trying to destroy it so such "heresy" never sees the light of day, and would most likely also see rogue elements of the Ad Mech trying to help them survive. So, literally, how much can they get away with? As much as the GM allows, which he could leave up to being as much as the setting allows.

A good point, which I brought up to my group. We looked for information on Rogue Traders, which is damned hard to find, but what we can find states that not only are they beyond the jurisdiction of the Tech Priests, but openly use Xenos tech on their ships, or even entire Xenos ships in their fleets*. Not that i'd let them get away scott free with the whole 'Tech Priests are gonna hate you', though.

*The source for that is Battlefleet Gothic Magazine, I will edit this with the actual issue number when I get it back, as one of my friends is barrowing it right now.

**EDIT** (Yes, I know, I was stupid enough to say i would edit this, and then have to edit it for something else XD )

Like i said in my first post, the original idea behind this post was just a character ship I made for fun, originally I never thought the idea would see the light of day, and I have no problem with the ship creation rules as they are now. I actually LIKE the restrictive give-and-take nature the current rules cause when designing a ship.