Freelancer discovery exact date & help with naval ranks

[Dantrithor]

Right, using this:
http://en.wikipedia.org/wiki/United_States...r_rank_insignia
and this:
http://en.wikipedia.org/wiki/United_States...d_rate_insignia

I have created this basic "skeleton" of the ship's crew ranks, and i need feedback about the ranks, if they are the appropiate, or not, or what to change. They are organized by role, and then by rank. The names are not yet put, till i get some help on what would be the jerarchical structure:

Total crew: 18

Ship's commander:
- Commander (OF-4)

Damage control:
On command: Petty Officer Third Class (OR-4)
- Fireman (OR-3)
- Fireman (OR-3)


Communications and Radar:

Comms officer: Lieutenant (OF-2)
Radar operator: Lieutenant (OF-2)

Support & Intendency:

On command: Petty Officer First Class
- Hospitalman (OR-3)
- Ensign (OF-1)
- Ensign (OF-1)
- Ensign (OF-1)

Weapons control:
On command: Lieutenant
- Main gun: Petty Officer Second class (OR-5)
- Cerberus Battery: Petty Officer Second Class (OR-5)
- Missile Battery 1: Petty Officer Third Class (OR-6)
- Missile Battery 2: Petty Officer Third Class (OR-6)
- Missile Battery 3: Petty Officer Third Class (OR-6)

Pilot:
- Lieutenant (OF-2)

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