I don't know if this will be more appreciated here than it was on the site I wrote it for, but here it is. It is essentially a short breakdown of the various paths available to people in various stages of life and education.
All of the paths here point towards an unrestricted line commission (Pilot, Naval Flight Officer, Surface Warfare, Submarines, and Special Warfare). If anyone shows interest, I will post more information about getting commissions into the other officer communities.
Paths to a Navy commission:
Starting point: High School
Choices: US Naval Academy or Navy Reserve Officers Training Corps
Starting point: College Sophomore
Choices: Bachelor Degree Completion Program, two year NROTC scholarship
Starting Point: College Senior or graduate
Choices: Officer Candidate School
Starting Point: Enlisted Sailor
Choices: USNA (<23 years old), NROTC scholarship (you will be discharged from active duty to participate), Seaman to Admiral 21
USNA: A four year military academy where active duty Midshipmen earn a bachelors degree while participating in an intense regimental training program. For civilians, a nomination from a Congressman is required to apply, and entry is extremely competitive. For currently enlisted sailors, applications are solicited for nomination from the SECNAV each year. There are 100 seats reserved each year at the Naval Academy for active duty Sailors and Marines.
Upon graduation, Midshipmen are commissioned as either Ensigns in the Navy or Second Lieutenants in the USMC.
NROTC: A program by which Midshipmen are trained part time while they attend civilian colleges and universities. Each semester, Midshipmen take at least one Naval Science course, participate in a leadership lab at least once a week, and PT at least once a week. Different NROTC units have different schedules. There are several ways to participate in the NROTC, but they can be summed into two categories: Scholarship and College Program. Scholarships come in 4, 3, and 2 year versions. 4 year scholarships are awarded to high school seniors prior to beginning. 3 year scholarships can be won by college program freshmen. 2 year scholarships are rare, and are usually granted to exceptional candidates who are already in their sophomore year and have not yet started NROTC. Even if no scholarship is granted, college program midshipmen can compete for a stipend through advanced standing after their sophomore year.
Upon completion of NROTC, Midshipmen are commissioned as either Ensigns in the Navy or Second Lieutenants in the USMC.
Officer Candidate School: A 12 week intensive training program where college graduates are trained to be Naval officers. Officer Candidates are trained by USMC Drill Instructors, Navy Recruit Division Commanders, and Naval Officers. OC's are expected to learn in 12 weeks what Midshipmen learn in four years. Upon graduation, Officer Candidates are commissioned as Ensigns in the Navy.
Bachelor Degree Completion Program: A program where college students can earn pay as active duty E3's (E6 for nuclear power candidates) for up to two years while completing their bachelors degree. Upon graduation, BDCP participants go to OCS.
STA 21: Out of all of the programs listed, STA 21 is the only one that is only available to Active Duty Sailors. It is an extremely competitive program. The program allows active duty Sailors to maintain pay, allowances and benefits while attending a civilian college and participating in NROTC. In addition, a scholarship good for up to $10,000 a year (to be paid directly to the school) is given. A selection board is held annually. Many of the selected sailors are sent to BOOST (Broadened Opportunity for Officer Selection and Training) prior to NSI, where they spend either three or six months in college prep learning math, science and English. All Sailors selected for STA 21 attend the Naval Science Institute at Officer Training Command, Newport, where they are designated Officer Candidates and spend the next two months learning navigation, basic naval engineering, weapons, naval history, as well as physical training. After NSI, Officer Candidates report to their assigned NROTC unit at a civilian college where they spend up to 36 months completing a bachelors degree. Once the degree is completed, the OCs are commissioned as Ensigns in the Navy.
One thing I do not recommend is enlisting with the intention of going to STA 21 or OCS. If you are a college grad, you should certainly apply straight to OCS. If you are not a college graduate, look into all of the available commissioning programs before you decide to enlist. Enlisted program recruiters are not very interested in your goals, and going to one with the intention of becoming an officer nearly always results in an enlistment. If you want to join as an officer, you should talk to an Officer Selection Officer (OSO). OSOs are not found in storefront recruiting offices, and enlisted recruiters will rarely refer you. In the links below you can find information regarding OSOs.
Officer Career Planner
US Naval Academy
NROTC website
Officer Training Command Pensacola (Officer Candidate School)
Seaman to Admiral 21 website