Nice! Is it based off of an airship from a book or game or something?
Nope. Completely original. I've always been fascinated by airships of all sorts, ranging from the classic rustic steampunk types, like the dirigibles along the lines of the Blackjack and Falcon from FF3/6, to the more modernized ones like the Highwind from FF7, to the outright exotic ones like FFX and X-2's Fahrenheit (FFX) and the Celsius (X-2), and then you have the crazy ones like the ones featured in FFXII. And that's just Final Fantasy's inspirations. I was also inspired by other series throughout the ages, like the small things from LEXX (season 3), for example. Can't list the rest off the top of my head, but there were others.
Anyway, this is supposed to be a battleship/med-capacity carrier armed with a Yin-Yang polarity cannon (regular energy cannon, but enhanced with magic, can also fire holy and demonic power, and as a de-facto nuke, both at the same time rotating in the form of a yin-yang for critical mass of spiritual energies resulting in a duality singularity blast of Absolution. In other words, a spirit-nuke, powered by a holy and arcane artifact with a secured connection to the perpetual generators linked with the 4D-μ (Mu, or Manipulation Unit). Naturally, combat rules frown upon the use of using a pair of stargates or a 4D-μ to place a gate at the muzzle and the receiving gate at a safe point away from the ship and making short work of a target (like melting a shield from 2 fixed points simultaneously). It also has a series of homing-laser secondary weapons, and rocket/missile/torpedo kinetic weapon alternatives alongside them, and a small battalion of auto-cannons lining the body for AA and smaller AS measures (preferred over machine guns). The ship can also carry up to 2 squadrons of fighters, and a small fleet of gunships (BAC-9 Barracudas (To-be rendered, another original design, with several varieties, from the Standard Gunship to Heavy Gunship, Recon/Racers, and construction "Bumblebees" mostly salvage-oriented)) of various varieties on board for ground combat and ship capture/salvage operations.
Alternatively, in order to follow combat rules, the ship has otherwise been designed to be really damn maneuverable for a carrier-battleship, with front-mounted thrust vector engines, as well as vector thrust on the backside, teamed up with pretty wide wings and ailerons, flaps, spoilers, and secondary rudder systems and air-anchors; with of course, internal ballast systems involving rather large brass-coated lead bricks (or decommissioned MAC-Cannon bullets used for demolishing starships from orbit), controlled via ferro-magnetic guidance systems with pulley systems for safety reasons. Simply put, this thing can actually do a snap-turn, and many other aerial maneuvers you'd never think a ship of such scale could ever pull off (it's got a dense infrastructure/skeleton especially on the wings to support the weight and stresses). The thing maneuvers like a race car in the skies, armed with nukes. Rumor has it that the entire crew is insane, and eggs on their pilot to go barnstorming with it, buzzing houses while upside-down, or power-sliding into a dry-dock, or even doing an immleman maneuver (upright half-loop to upright orientation again) . To be crew to this ship, you better have good G-force resistance, a strong stomach, and balls made of adamantium-plated dark matter.
I have the picture I'm using for reference, as well as something I want to be able to accomplish for rendering reasons.
Progress Update:
Just added the upper-main mid-front fuselage portion, and the main cannon attached to it. Going to add more to the back end to complete this portion of the mid-fuselage. Once that "Abdomen" is done, I'll work on the "Thorax" of it where the quarters, research and recreation/briefing rooms (or an on-board bar/tavern, really) are established, along with the main engine where the intakes linkup.
When that's done, the wings will be worked on, and basing off the backside's form, I can more accurately establish how long it can be built to look correct. Thanks to being made in pieces, adjustments and repairs shouldn't be too hard, as would be skinning it later on, I suppose.
UPDATE EDIT:
As you can notice, both bridges have a decent enough offset from the main cannon that they can both aim the main cannon forward. Especially useful when both bridges work in tandem with each other. Nice to know, operating them in tandem, seeing as they both have rather colossal blind spots to work with, but can complement each other. If going single-bridge with a single crew, there's an elevator, Enterprise-ish, that can allow the crew to switch bridges in a jiffy; and alternatively, a slide through the maintainence ducts is also a direct way between bridges as well (best done during auto-pilot or hover/stationary "sitting duck" mode).
The big flat areas you see are where the back wings are going to be fitted, and the rather large flat backside is where the ship's Thorax will be put in place. And yes, you can walk topside. The doors are big enough to allow medium-large cargo to slip through.
EDIT EDIT:
I am aware that the 3-D model is looking a little different from the drawing already, but I figure, since I made it about 6 years ago, I might as well update it. I had some ideas form over time since I drew it, and figured, since I'm building it from scratch (again) why not re-imagine a few features? I like some of the adjustments.
Oh, another game of inspiration for ship design has to go to Starcon, Master of Orion, and Endless Space.