O'Brien's rank

[Tomalak]

"I've come to fix your warp manifold..."

 

[Shamrock Holmes]

My take on the O'Brien engineer/Tactical officer thing was that he was originally an Armory Specialist, an engineer who is specifically trained in the construction, maintenance and firing of weapon systems and related power systems (similar to Reed, and possibly Shelby) rather than a 'general' engineer like Scotty, LaForge et al.

As far as the actual rank issue goes... I'm still confused on that one.

Shamrock Holmes

 

[C.E. Evans]

I think Starfleet places more emphasis on positions rather than ranks. O'Brien may have been carrying out the role of a tactical officer, even if his actual rank was that of a senior enlisted/noncom. It'd almost be akin to referring to a cop as a police officer even if he was actually a sergeant, IMO.

 

[Ro_Laren]

Ah yes, the old O'Brien's rank debate. IMO it was unbelievable that a Chief would be in charge of a department on a space ship or the Chief Engineer on a ship like the Defiant. I think the producers kept calling his character "Chief" because everyone got used to it on TNG. The producers were not interested in logic or making the show realistic to those that have any knowledge of miliary ranks and protocol.