Example
At the start of the template, prior to the overview, you should include a line or two about the ship itself as well as the class name at the top of the article.
Overview
Class: The name of the ship class
Operators: Who uses this ship?
Manufacturer: Who manufactures this ship?
Length: Length of the ship in Meters
Diameter: Diameter of the ship. Though if your ship is more plane-like you may want to use Width and Height here instead of Diameter
Width: Width of the ship in meters, though if the ship is rocket-shaped you may want to use Diameter instead
Length: Length of the ship in meters.
Crew: The standard number of crew required to man the ship
Propulsion: The name of the ship's primary engines.
Maximum Acceleration: How fast the ship can accelerate in Gs. See:
Ship Acceleration
Avionics: A list of control systems onboard the ship
Communications: A list of communication systems onboard the ship
Sensors: A list of the name and number of sensor systems on the ship
Armament: A list of the name and numbers of weapon systems on the ship
Cargo Capacity: The cargo capacity of the ship, or the number of cargo containers it can carry.
Support Craft: A list of the name and numbers of the support craft carried by the ship.
History
The history section should include a paragraph or two on why this ship was developed, how it was designed, and when it was put into service. If there is more history or current events related to the ship class it should go here as well.
Layout
The layout of the ship, and where its internal components can be found. This can be broken up into smaller sub-headers to cover the individual components.
Armor
What kind of protection does your ship have? At minimum there should be some kind of protection against radiation: Both from space and from the ship's reactor. Many ships will also have protection against micro-meteors and some will carry heavy armor to protect against weapon strikes.
Weapons
What kind of weapon systems are installed on the craft?
Life Support
What kind of life support systems are installed on the craft? Does the ship have oxygen recycling or do the crew need to wear space suits? Is there grey-water recycling and hydroponics? Or does the crew rely on supplies stored onboard?
See:
Life Support