In commercial aviation, the first officer is the second pilot of an aircraft. They are subordinate to the Captain, though many airlines promote by seniority within their own company only, so the first officer may actually have more flying hours than the captain, for instance as a military pilot or with other airlines. Traditionally, they sit on the right hand side of a fixed wing aircraft, or the left of a helicopter. Aviation or Air transport refers to the activities surrounding mechanical flight and the aircraft industry. ... Aviators are people who fly aircraft either for pleasure or for a job. ... An aircraft is any machine capable of atmospheric flight. ... Captain is both a nautical term and a military rank. ...
First Class Petty Officers normally serve as a Leading Petty Officer (LPO) of a division, and may direct the activities of a division in the absence of the division Chief Petty Officer.
The term petty officer is, then, only used in abstract, the general sense, when referring to a group of petty officers of different ratings, or when the petty officer's rating is unknown.
It is common practice to refer to the petty officer by this short hand in all but the most formal correspondence (such as printing and inscription on awards).
Even when the firstofficer is flying, the captain remains ultimately responsible for the aircraft and its passengers and crew.
Because many airlines promote by seniority within their own company only, the firstofficer may at times have more flying hours than the captain, for instance with other airlines, or as a military pilot.